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thinking of ford 8.8 rear end swap

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Old 03-02-2009, 09:16 AM
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Re: thinking of ford 8.8 rear end swap

The '79-'93 FOX Mustang is 59 1/2 inches wide, 1/2 inch less that the first gen Camaro.
Old 03-02-2009, 02:16 PM
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Re: thinking of ford 8.8 rear end swap

I've got to big of head ache to read all that right now.

Sorry man, I've just had a lot going on as of late and haven't had a chance to get any pics while near this car. It's at a buddies house in his '68 stang project. The car is now a full tube chassis with late-model stang strut front suspension and a tq arm rear link set-up with coil-overs all around. It will be a 4-valve 4.6 with a large single turbo, pushing around 600rwhp and I intend to get a minimum of a mid 1.6 60' out of it with full interior, a/c, manual trans and 17" wheels. - Just noting that for reference as to what I designed it to withstand.

Looks like some of Granny's designes are different, but I'm not seeing an adjustable pinion angle in several of those pics, but maybe I'm missing something. Pinion angle is a major key to getting a suspension tuned well, especially if you're running street tires with small sidewalls.

As for the strength comparison of a 12-bolt vs an 8.8, that's still largely up in the air. There are drag radial guys running low 5's in the 1/8 on 8.8's, I've seen some 4 sec cars on them as well. At the same time my car is still currently on a 12-bolt and has already seen 1.26 60fts with just a NA 468, I'm going to hit it with 250 on a WOT switch and see if I can kill it before I put the S60 in.
Old 03-02-2009, 03:59 PM
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Re: thinking of ford 8.8 rear end swap

Our TA steups are designed for our RX-7 V8 conversions, so the pinion angle for that is designed into the package. If we need to change it for some reason, different length side plates are all that is needed.

Supply is an important consideration for me. If i send my guy out to pick up five 12 bolts, he would probably have to drive all over hell and be gone for a week...one here, another there, and we would probably have to pay a premium for every one of them. On the other hand, I can get ten 8.8 crown vic rears in a single stop...although that is at a wrecking yard that specializes in taxi cabs and police cars. For me, it's an easy choice.

Granny
Old 03-03-2009, 03:40 PM
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Re: thinking of ford 8.8 rear end swap

Originally Posted by Granny
Our TA steups are designed for our RX-7 V8 conversions, so the pinion angle for that is designed into the package. If we need to change it for some reason, different length side plates are all that is needed.

Supply is an important consideration for me. If i send my guy out to pick up five 12 bolts, he would probably have to drive all over hell and be gone for a week...one here, another there, and we would probably have to pay a premium for every one of them. On the other hand, I can get ten 8.8 crown vic rears in a single stop...although that is at a wrecking yard that specializes in taxi cabs and police cars. For me, it's an easy choice.

Granny
That makes sense. - Some great info about 8.8's too, thank you for that.

I personally throw axles and such out the window from the get-go knowing that if I need a stronger rear than the 7.5, I need more than just stock axles. I've been fairly solidly into the 11's on my 7.5 doing 5k+ clutch drops. The key being it's a 3.73 gear. It needed about a 4.30-4.56, but then it would have never lived.
Old 03-03-2009, 04:03 PM
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Re: thinking of ford 8.8 rear end swap

Actually, I know of one guy running an 8.8" center, and the tubes from his original 7.625" He's in the 10s on drag radials, with just 31 spline axles. The car is no lightweight.
I got my 8.8 housing from an '87 Cougar XR7, at Pick-N-Pull, for $75 plus a $5 core charge. Shoulda waited for half-price day. This one came with larger drums than a Mustang 8.8, but 2.73:1 and 28-spline, 4-lug with a well-worn Traction-Lok. Lincoln Mark VII LSCs also used an 8.8, but with 5-lug and 3.27:1. T-bird SuperCoupes and TurboCoupes also used the 8.8, and F150s are a good source of long 31-spline axles and the 3.55:1, 3.73:1 and 4.10:1 gear sets.
Old 03-05-2009, 05:31 AM
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Re: thinking of ford 8.8 rear end swap

well ive been looking around and have found afew fox body 8.8s for sale but no crown vic rears. tday since its 630am in NJ i will be going to a couple salvage yards. hopeing one of them is still open. and the other is known for its over pricing. im gona try to pick up a crown vic rear for about 200$ cash since thats what im bringing with me. hopefully i find one. and i'll report back
Old 03-07-2009, 09:11 AM
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Re: thinking of ford 8.8 rear end swap

ok this is what ive found. one junk/salvage yard that is a pick ur part had 2 crown vics. at 97 and a 99. one had a 8.8 but was a 2.73 and not a locker. the other was the smaller 7.5" ford. i snuck out with 2 calipers from one of the cars.

tday i went to another salvage yard. had a few 8.8s but only one out of a 97 police car. found the rear. rear had no ID tag on the cover bolts. it had disk brakes but i went and took the calipers off. the rotors where rusted to the housings but when i pulled on the axle ends there had to be like 1/4" of play in them. not to mention u turned the wheel and the other would turn in the opposite direction(means it had a posi) but that i could turn the wheels in opposite and twist them back and forth as another guy turned the other axle. the posi had to have been shot. i measured the length from the studs where they meet the brake rotor and the crown vic rear was 64" total length, my stock 9bolt is 62".

he wanted 300$ for it. i turned him down. i also saw a 10bolt out of a 99 firebird... but didnt even bother since they are too weak. i guess i'll have to keep looking... too bad theres nothing here
Old 03-07-2009, 09:24 AM
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Re: thinking of ford 8.8 rear end swap

No, if the wheels turn in the oposite directions, then its an open rear, or has a locker that is open when unlocked. If it were posi, meaning clutch packs, then they would turn in the same direction.
Old 03-07-2009, 09:30 AM
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Re: thinking of ford 8.8 rear end swap

The Traction Lock in the 8.8 can be easily rebuilt. I have clutches for them and you can add extra clutch platres to make the lock up better. Don't pass one up just becasue the clutches are worn.

By the way, when you have excess axle end play like you described that means that the clutches were worn. Replacing the clutches will reduce the end play.
Old 03-07-2009, 09:59 AM
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Re: thinking of ford 8.8 rear end swap

from what ive heard/ppl have told me the rear wheels should spin in opposite directions if one wheel is turned. if it doesnt have posi the other wheel shouldnt turn at all. both of my firebirds have 9bolts and had posi's. one is a 2.77 and 3.27... both have the opposite wheel turn in the opposite direction when turned. am i wrong?

i kno they are rebuildable but i was unsure with the gearset and the guy wouldnt let me pull the cover to figure it out. as i stated the cover didnt have and ID tag. i also think the 300$ is a bit steep for a badly worn 8.8 from a 97 police car and it was sitting outside in the weather for a couple of years.

how much are the rebuildable clutch packs?
Old 03-07-2009, 10:05 AM
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Re: thinking of ford 8.8 rear end swap

The GM posi is the gov lok G80, it is kinda both a clutch and locker I guess, it will work as an open diff, but when it locks up with loss of traction, both tires will spin in the same direction. It can disengage.

With the ford posi, it is all clutch packs, and IIRC there arent any spider gears, so the wheels would always turn in the same direction if the clutches are good. One axle is locked to the ring gear/carrier, so it will always spin, the other axle is clutched to the carrier, and can slip.

I hope I'm describing this right and not confusing.

Oh, and the Ford trac lok is weak I hear. One I got was cracked from bolt to bolt to bolt holding the thing together. I don't think they handle shock well, so if you use an auto trans, it would probably be ok, if you don't smack the drivetrain slack much.

Don't smack the slack!!
Old 03-07-2009, 10:11 AM
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Re: thinking of ford 8.8 rear end swap

A good working limited slip differential, or "posi", will turn both axles in the same direction. If they turn in opposite directions or one doesn't turn at all then it is a standard differentil or a worn out LSD.

If you want to know what the gear ratio is then turn both axles exactly one full turn and count the number of turns that the yoke makes. If the yoke turns 2 3/4 times then it is a 2.73, if it turns just past 3 1/2 times it is a 3.55, if it turns 3 3/4 times then it is a 3.73...

I'll have to check the price on the clutches. I can't remember how much they are.
Old 03-07-2009, 10:16 AM
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Re: thinking of ford 8.8 rear end swap


This is the 8.8 Traction Lock. You can see that there are clutches behind both axle gears. This is a fairly strong differential. The problem with these is that the stock clutcues don't hold up well to burnouts.


This is the 9 inch Ford Traction Lock. Notice the cover is busted. This is comon for these differentials. They don't hold up well to abuse. This one was broke by a stock 390 with an automatic in a 4X4 truck.
Old 03-07-2009, 10:29 AM
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Re: thinking of ford 8.8 rear end swap

Oh, I didn't know they were different. On the 8.8, is that a spring in the center to take up slack from wearing clutches?
Old 03-07-2009, 10:40 AM
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Re: thinking of ford 8.8 rear end swap

That's the preload spring. It applies pressure to the clutches to help them lock up. The Eaton has 4 coil springs, which can be changed for different preload amounts. The Auburn has 5 coil springs and there are 2 different preload amounts for it. The 9 inch has 4 coil springs in a steel block located in the center of the differential. The 8.5 GM Traction Lock has the same S shaped spring as the 8.8 Ford Traction Lock.
Old 03-07-2009, 10:48 AM
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Re: thinking of ford 8.8 rear end swap

yea thats what i thought the trac lock looked like. so if it has a posi the wheels should turn in the same direction? so if i turn the passenger rear the driver wheel should turn in the same direction? or is the oppossite direction correct? i kno about looking at the yoke but the posi musta been worn so badly that it would turn the same as the wheels. when i turned the passenger wheel the driver wheel would turn opposite direction. they then would both turn the yoke didnt matter which wheel was turned. but each wheel could be turned against each other with no restriciton. pretty sure all police rears had posi, just didnt want to pay 300 for a busted posi, no brakes and i couldnt tell wat gears it had.

my friend has a stock rear fox body with a 150 shot and hes pullin 1.6 60fts with slicks and runs high 11s and the rear is fine. id say they can be pretty strong. can extra clutches be added for increased strength? i saw a clutch rebuild for something like 80$ on line i think.

my car will have 500hp at the crank. a 2500 stall and a built 700r4 with billet servos and all the goodies.
Old 03-07-2009, 10:55 AM
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Re: thinking of ford 8.8 rear end swap

Both axles will turn together in the same direction if it has a good working posi. The stock TractionLock has 3 friction plates on each side. I can add one more per side to increase the lock up. If you look at the one in the picture you can see that it has 4 friction plates on each side (the plates with the ears on them).
Old 03-07-2009, 10:58 AM
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Re: thinking of ford 8.8 rear end swap

so is 300 too much for that rear? prob with northern NJ is availability. now much does the extra clutch increase lock up? over stock
Old 03-07-2009, 01:43 PM
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Re: thinking of ford 8.8 rear end swap

The TracLoc's design is such that the angle of the spyder gear teeth provide most of the clutch pack's compression...the more power that goes thru it, the more clutch clamping force and lock-up you will see. This is why you see failures such as those in big gear head's pic...a lot of power was passing thru the TracLoc's case without any extra support from the housing, usually due to a poorly pre-loaded set of diff bearings. Proper side bearing pre-load adds to the TracLoc's power capacity.

During a water burnout, not much power is needed to spin the tires, so not much clamping force is applied to the clutches...this is why they lock up poorly during burnouts. The "S" shaped spring is there for clutch pre-load, mostly to provide clutch pressure when there is no traction at all (and little power passing thru the spyders) such as ice/snow/wet/etc. Under minimum traction conditions such as these, without the "S" spring's pre-load, even a brand new 8.8 TracLoc would lose all it's limited slip abilities. If you want to add clutch pack pre-load, the F-150's got a thicker/heavier/stronger pre-load spring.

As a side note, it's pretty common for road racers to run the 8.8 TracLoc without any "S" shaped pre-load spring at all...relying solely on the spyder gear's tooth angles to load the clutch packs under hi load conditions, but unlocking the diff under low load conditions, making it easier to recover if the car is driven past it's limits.

An 8.8 with an open diff usually has very little axle end play, and spinning one tire by hand will result in the other tire easily spinning in the opposite direction if the pinion is held.
An 8.8 with a TracLock w/ fresh clutches and normal clutch pre-load will have little axle end-play and will act as if the tires are mounted on the same axle. It will take a bit of effort to overcome the pre-load, at which point spinning one tire will cause the opposite tire to spin in the opposite direction if the pinion is held. It will ultimately act the same as an open diff, but it will take a lot of effort to make that happen.
If you see a lot of axle end play, that's almost a dead givaway of a TracLoc with worn or damaged clutches. You may feel some resistance from the clutches if the pinion is held, but you may not. 8.8 TracLocs are easily rebuilt, so it's usually not the end of the world if it shows a lot of wear. Clutch set prices vary from around $65-$120...usually the best deals are to be found in the Mustang mag ads.

If you are looking for a 8.8 28 spline TracLoc, i've got about 15 used ones sitting on the shelf...i'll send you one for the cost of shipping.

Granny
Old 03-07-2009, 08:53 PM
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Re: thinking of ford 8.8 rear end swap

thanks granny. im gona have to buy u a beer someday lol.

so the wheels should spin in the same direction then if the posi is good. as i said the the passenger wheel had ALOT of play in it. something like 1/4 inch it was disgusting. the driver wheel had alot less play. the wheels weither spinned together or opposite had little to no resistence to eachother. but both would move the pinon when turned independently.

i just stuck my 9bolt on jack stands today and did the same wheel spin test. my stock 9bolt did the same thing. i spun the pass wheel and the driver spun in the opposite direction. both moved the pinon and it took alil effort to overcome the posi ot spin in the opposite direction. now i kno my 9bolt has a posi and 3.27 gears. but when i spin the rear tires the other tire does not spin in the same direction! ugh

could u ship quote a used posi to 07052 NJ for me? id def like to get whole of one and rebuild it and then slap it into a rear. since it might be some time before i get one. that way it doenst matter what i get as far as a posi or open rear i could just drop one in! and now i just have to find a gearset i like.

does taking out the Sspring decrease the rears strength at all? so by taking it out it acts like a open diff untill u get on it enough for the syder gears to lock the rear. this wouldnt burn up the clutches faster?

also the shear size of the ford 8.8 over the 9bolt/10bolt is amazing. the 8,8 is a butt load larger than the stock 3rd gen rears. even the center case is huge and looks a CR@P load more stronger. should i have bought the 300$ rear? lol my 9bolt is so puny when i look at it now that ive seen a ford 8.8

Last edited by customblackbird; 03-07-2009 at 08:57 PM.
Old 03-07-2009, 09:17 PM
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Re: thinking of ford 8.8 rear end swap

Keep looking for a good rear end. $300 might have been all right, but you can probably find one better. As for rebuilding a stock 28 spline Traction Lock, don't you need a 31 spline unit?

Look in F150 trucks for a good gear. Many of them had 3.55 or 3.73 gears. If you want a 4.11 I have a NEW Ford Motorsprots gear for sale.
Old 03-07-2009, 09:36 PM
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Re: thinking of ford 8.8 rear end swap

im not upgrading to the 31 spline axels/posi etc untill i put down enough power. id rather cheaply throw in a working 28spline 8.8 with maybe a rebuilt posi so it will last a couple of years. the motor isnt gona be crazy off the bat. im guessing 400hp or a lil less at the rear wheels. should be making 480hp at the motor. i would think the ford 8.8 with 28spline axles and a good posi would hold up. car will be mostly street driven. later down the road im gona throw a 100-150shot at it. i would think the 28spline with posi with extra clutch will suffice. i just want something cheap and stronger than my 9bolt that i can upgrade easily in the future and i didnt want to spend 2800-3000$ on a 12bolt/9in.

id be happy with a 3.23-3.73 gearset. since car will be daily driven i def dont want the 4.11s. my HSR will like the 3.55/3.73s and since i calculate somwhere around 14mpg with the 30lb ford SVO injectors with my 3.27 stock gears. i dont want to steep a gear and kill my MPG
Old 03-07-2009, 09:55 PM
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Re: thinking of ford 8.8 rear end swap

I've got quite a few used 3.27 and 3.55 gearsets, all w/ the original pinion shim.
Same deal as the diff, no charge for a set except for shipping. My customers always want any used 3.73's i come across.

Granny
Old 03-07-2009, 11:44 PM
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Re: thinking of ford 8.8 rear end swap

No personal experience w/o the preload spring, but it seems to me that the clutches would likely wear less...they would not be forced to slip against the preload around every corner.

Shipping would likely be around $25 for the diff, and $25. for a r&p set.

Pretty sure there is something out there cheaper than $300., but maybe it's not worth the extra time and travel to search it out. Around here, a typical yard will ask $200. for a complete rear, does not matter if it has disc or drum, open or limited slip.

Granny
Old 03-08-2009, 11:37 AM
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Re: thinking of ford 8.8 rear end swap

im def interested in the gearsets and posi's. i would like to go with the 3.55 gear sets. do u also sell the posi clutch rebuild kits? let me kno how u want to do the payment etc. the gear sets are good right? and the posis are just worn but not damaged etc?

so i can install the posi and ring and pinon into an open diff if i find one and call it a day. better if i find a posi rear and just swap it out. the pumpkins are all interchangable right? so it doesnt really matter the year correct? or if the rear is a posi or not?

the pick your part salvage yard i was at has a 8.8 but it wasnt a posi but it had disk brakes. they said it would be 200$. i could live with that. so if i could just throw in your posi after i rebuilt it and the ring/pinon and a new install kit and be done with it that would be amazing.
Old 03-08-2009, 02:13 PM
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Re: thinking of ford 8.8 rear end swap

So I guess you are going to use the axles as they are. I was thinking that you were going to cut the rear end to fit the car and get axles to fit. That is why I was thinking that you needed to go with the 31 spline parts instead of using 28 spline stuff and then having to get all new stuff again later.
Old 03-09-2009, 12:41 PM
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Re: thinking of ford 8.8 rear end swap

my plan was to originally use the stock axles, stock posi etc. just change out the fluid. im looking for a cheap alternative to my 130,000 mile 9bolt that wont die behind 480crank HP, and that i could upgrade later down the road when needed.

my biggest dilema is the wheel/rear combo. if i go with the crown vic rear its overall about 64" vs the 62" stock 9bolt. and the 5lug pattern is 5x4.5" vs the stock chevy 5x4.75... so my SLP wheels wont fit. which means if i keep the stock 28spline ford axles i would have to go with aftermarket ford rims with the correct backspacing/offset. or i could just upgrade the axles to stronger moser 28spline and hopefully get the chevy wheel bolt pattern. can this be done? i would like to throw wider tires like 10" wide rims on the back. bc i can smoke my 245/45/r17 nitto 555s real real easy with my lightly modded L98.

but if i upgrade the axles this would be pointless bc later down the road i kno im gona have to throw 31spline stuff in there say with a 150shot. im looking for the most cost effective for right now.

so i have leave the 8.8 the same and get ford aftermarket rims for the bolt pattern.

or get new axles for chevy bolt pattern and throw stockers back on. i do need new tires since my nittos are bald on the rear.
Old 03-09-2009, 12:59 PM
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Re: thinking of ford 8.8 rear end swap

With GM, when you turn one wheel one way, and the other wheel turns the opposite way, that means there is NOT a limited-slip in there. The ford traction lock behaves a little different, and will allow a little but of that before tightening up. Sometimes when doing a burnout out of the water box, it would do that. I let my buddy drive my mustang so I could watch, and it's true! Spend a minute and pull the cover to see for yourself if it has the T-L or not. He said it felt like it was spinning the right tire, then the left. Well, it was the right, then both, I was behind the car, with a clear poly faceshield on.
Old 03-09-2009, 01:11 PM
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Re: thinking of ford 8.8 rear end swap

ive already checked the rear. it was the stock 9bolt. car is a stock formula 350tpi. all 350tpis got limited slip diffs. i checked the gear ratio and its the 3.27. and the RPO code for the limited slip is there. it does have the stock limited slip in there. my 86TA with the 9bolt and 2.77 does the same thing and it has a limited slip. they are just worn bc when i went to the track i only got rubber on the pass side wheel well.

the other wheel turns the opposite way but they both turn the pinon. u can feel how both axles are connected just by turning anyone of the wheels.
Old 03-09-2009, 01:58 PM
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Re: thinking of ford 8.8 rear end swap

This is whay I was wondering about the 28 spline parts. What I'm suggesting is that you just go ahead and do it right the first time and then you don't waste any money when you have to replace parts the second time. If you get a Crown Vic rear end and narrow it to fit your car, then get the correct Moser 31 spline axles and 31 spline Traction Lock you won't have to go back and do it all over again later. You don't waste money on wheels, 28 spline axles, 28 spline traction lock rebuild or any of that stuff. Get the housing narrowed and get the pinion offset correct. Then build the brackets that you need to hold it all in place. Do it once right and you don't have to do it again. You are so set on trying to save money on this that you are going to end up spending more money on it than you need to. Just my opinion.
Old 03-09-2009, 02:33 PM
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Re: thinking of ford 8.8 rear end swap

Well this can change everything. No cars came with 31 spline?

Why not the GM 8.5? Cut and narrow a truck 8.8 or 9".

I see what you want to do. You don't want to spend all the money up front. You want something decent that you can build on as you have money. But gear head is right, you go buying extra wheels and crap for 28 spline you don't even want, you're doing extra work and wasting money.

I would definitely start with something 31 spline.


If you are going to have to narrow, its actually pretty cheap. You can cut and reweld the axle tubes yourself, and to have a machinist cut and respline the axles should only be about 40 bucks, if that.

I think it could still be done cheaply.
Old 03-09-2009, 02:52 PM
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Re: thinking of ford 8.8 rear end swap

i figured the stock 28spline axles and posi would last. but if it were to break i would then upgrade. oh no i kno all about doin it right the first time. but a ford 8.8 with 28spline axles can take one hell of a beating... and mine will be a daily driver with an auto might get slight track use so it wont get beat on too badly. someone posted that u can redrill for the chevy bolt pattern. or get an adapter. these are cheap from Skulte.com.

the 1" increase in rear end length from stock on each wheel is no biggie and my stock rims i believe would still fit. id rather the rear be alittle wider so i would be able to run more backspacing/offset for a set of aftermarket rims. if you notice there are not many rims available for 3rd gen firebirds. but a whole bunch for 4th gens and there rears are 2" wider than ours on both sides.

i wouldnt think spending 100$ on a rebuild kit for a 8.8 and throwing it all back together... would be that much of a waste of money. i would like to have the axle ends redrilled for my chevy pattern or just spend alil more on adapters so i can run my stock wheels. and the 28spline ford 8.8 is still stronger than my stock 9bolt or 10bolt. maybe 200$ for an axle and 200$ for a rebuild kit for trac lock and adapters wouldnt be to bad to last a few yrs before i juice it. budget is tight now and i want the car to get done. still need to get a short block before car can run.

i chose the 8.8 bc they seem to be readily avaliable (not by me tho)and are cheap to get parts for. plus theres an insane amount of procducts for them. and they can be stronger than 12bolts and weight a bunch less etc.

ford explorers cam with 31 spline but used the larger 9" bearings so u have to use an explorer housing or modify the end of the axle tubes on a reg 8.8
Old 03-09-2009, 03:09 PM
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Re: thinking of ford 8.8 rear end swap

Before the Explorer got the 31 spline, us Mustang guys were making use of F150 axles to go 31 spline in our 8.8s, without having to do anything exotic to our wheel bearings or the housing ends they live in.
Old 03-09-2009, 07:49 PM
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Re: thinking of ford 8.8 rear end swap

About the only way to make the low buck 28 spline option worth it is to get the width you want without spending money on narrowing, re-drilling, buying spacers or special wheels. If you are going to need to buy adapters to get what you want, you would probably be better off spending $350 on a set of custom aftermarket 31 spline c-clip axles with your bolt pattern already on them. If you are tight on budget, maybe go with a 31 spline open diff until you find the right deal on a limited slip.

Later Crown Vics are wider at 64-1/4" rotor flange/rotor flange, but back in the mid-'80s, the Lincoln Mk7 was only 61-13/16" rotor flange/rotor flange. The big difference is that the later axles were longer and stuck out farther to allow room for the ABS tone rings. The housings are not interchangable though, as the axle tubes have different bolt patterns for the caliper brackets.

The Explorer has bigger axles/bearings than the cars, but they are just bigger versions of the 8.8 car bearings where the rollers ride directly on the axle surface, nothing like the 9's self contained bearing.

F-150 31 spline diff will fit right in the car housings without any mods except in some cases removing the tone ring, but i'm not aware of any 31 spline F-150 axles that will bolt right into a Mustang housing w/o mods.

Granny
Old 03-10-2009, 04:04 AM
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Re: thinking of ford 8.8 rear end swap

so your saying that a diff year posi wont fit in a diff year ford 8.8? the posi's arent all the same essentially?

my plan was to do this, cheap is find a cheap open 8.8. maybe even just a housing, then rebuild the posi that i want u to send me, then throw in the 3.55 gears. and perhaps just get a set of moser 28spline axles with the chevy bolt pattern. that way i can run my SLPs and when i decide to go to 31spline i can give my 28spline axels to my dad since i will prob have to make and find a ford 8.8 for him, since his 9bolt is toasted in his 86 TA. i dont mind the axel length beind 64 1/4" vs the stock 62" thats only a inch wider than stock on each side and is still shorter than the 4th gen. so i should have clearance with my SLPs.
Old 03-10-2009, 06:35 PM
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Re: thinking of ford 8.8 rear end swap

All the 8.8 diffs, open or limited slip, are interchangable and have the same external dimensions, w/ the exception of the axle spline differences. Some trucks use a lightly pressed on ABS tone ring that sits behind the ring gear. I'm not sure that that ring would fit in a car housing, but it's easy to remove if the ring gear is off, just light hammer taps, no cutting/grinding required.

The 3rd paragragh in post #84 was referring to the axle bearing differences. The diff bearings are exactly the same.

Granny
Old 03-11-2009, 02:08 AM
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Re: thinking of ford 8.8 rear end swap

ok good. i was also hessitent buying that 300$ 97 crown vic rear due to it having ABS sensors on it. which is this ABS tone ring ur talking about. as well as the sensors behind the brake caliper brackets. i didnt want to take out the ABS tone rings and then have fittment issues. when i try to put everything back.

so what do u want to do about that posi and 3.55 gear set?
Old 03-11-2009, 10:26 AM
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Re: thinking of ford 8.8 rear end swap

Just send me a PM w/ your mailing address

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Old 03-11-2009, 02:04 PM
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Re: thinking of ford 8.8 rear end swap

pm sent
Old 03-16-2009, 07:17 AM
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Re: thinking of ford 8.8 rear end swap

...better late than never....
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Old 03-16-2009, 09:54 AM
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Re: thinking of ford 8.8 rear end swap

its not to late shagwell! thanks for the idea. i didnt even think about that. does that bolt up to a spohn tq arm mount? or did u fab up the actual tq arm mount?

also tubing DIA and thinkness? that might be another route but it would mean id have to weld the tubes to the pumpkin as well as it not be removable.
Old 03-16-2009, 01:18 PM
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Re: thinking of ford 8.8 rear end swap

The mount eye plates top and bottom bolt directly to the tq arm. No reason for any sort of bracket with a custom arm. - I'll try to get some pics (next Sat when we work on it again) of it with the arm in place. We ran out of wire and didn't get the arm finished this past weekend.
Old 03-23-2009, 03:12 PM
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Re: thinking of ford 8.8 rear end swap

just saw a explorer 8.8 for sale complete in NJ on craigs list. listed in NJ somewhat close to my house and its 150$ has disk brakes etc.... im tempted to buy it but i kno granny said the explorer rear ends weigh alot more. still tho should i?

i also just purchased the posi and 3.55 gears from granny. but its for a 28spline axels. im gona be getting a new posi clutch rebuild kit but im unsure about which to get. i can get a stock clutch rebuild kit ford racing for about 50-70$ has all new shims and steels and friction modifyer. then i would add 1 clutch to each side from the old posi for extra strength and locking abilities. or....

should i get ford racings carbon fiber clutch pack that is for high tq applications. stronger than stock and is used in all stock 2003 up SVT mustangs. kit is about 104$ and has everytthing and is already shimmed etc and each clutch pack is already assemebled for each side, i just have to install it. no clearanceing etc.

would the carbon fiber clutch pack be a stronger better choice? or are a extra clutch in a stock rebuild posi clutch pack?
Old 04-01-2009, 10:28 AM
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Re: thinking of ford 8.8 rear end swap

I am doing this ALSO NOW!!!!!

my local junyard has bunches of the new crown vics. The length is perfect me because i have a 4th gen rear with a offset proper to it so it should fit perfect.

and tomorrow the junkyard is having a 50% off everything sale.

!!!!!!
Old 04-01-2009, 03:52 PM
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Re: thinking of ford 8.8 rear end swap

We just recently had a new yard open up(haven't had one at all in a few years). Hoping to get out there myself shortly and see if I can kick-up an explorer 8.8 for my s-blazer.
Old 04-01-2009, 04:02 PM
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Re: thinking of ford 8.8 rear end swap

Yea, I hear they drop right up. It would be the perfect upgrade for my budget 5.3 S10 project.
Old 04-02-2009, 01:29 PM
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Re: thinking of ford 8.8 rear end swap

Originally Posted by Batass
Yea, I hear they drop right up. It would be the perfect upgrade for my budget 5.3 S10 project.
Basically, yes. I need to check the exact widths to see if I can fit a set of 15x10's; I've got access to a good deal on a new set with a 4.5 bs. - I had been planning to run GTA wheels(all rev offset, so probably a 1/2 spacer plus new studs) but I''ve got some 15x3 fronts that would match these and I'm thinking abou it pretty hard.

/end thread jack....
Old 04-02-2009, 03:25 PM
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Re: thinking of ford 8.8 rear end swap

I just picked up a 8.8 out of a 99 police interceptor crown vic.
70 buc complete with disc brakes. pulled it out today. 3.55 gears and they are in great shape.

All i need to do now is find out how long my ls1 diff is. i measured the crown vic rear at like 65 inches.
Old 04-02-2009, 07:54 PM
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Re: thinking of ford 8.8 rear end swap

hey Granny, sounds like you'd make some money fabbing torque arm mounts fror GM 8.5s and ford 8.8s for use in an F-body
Old 04-02-2009, 08:53 PM
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Re: thinking of ford 8.8 rear end swap

Originally Posted by GTFiero
hey Granny, sounds like you'd make some money fabbing torque arm mounts fror GM 8.5s and ford 8.8s for use in an F-body
lol i was gona say the same thing lol. its the only thing that holds us back! im pretty upset u found a ford 8.8 outa 99 police car for 70$.... i would kill for that kinda deal up north here!!! D@MN JERSEY!!!!! mind shipping one up here? lol

just an update, havent had alot of time to look for rear ends but i recieved grannys posi unit and 3.55 gears... just recieved my summit order that had new ford racing ring gear bolts and i also got the new Carbon Fiber clutch packs for the posi.

quick question... dont the ring gear bolts have washers? the new bolts i got didnt have washers with it, my dad says that ring gear bolts usually have washers. i got ford racing bc i couldnt find ARP bolts for the 8.8.


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