Maverick H1L

iTrader: (8)

If the parts guy at the dealer doesn't have it when he calls in the morning, I'll give him that one and see if he can or needs to cross-reference it to find it.

JamesC

iTrader: (5)

FWIW, the part # is good at GMPartsDirect.

JamesC

Slayze

iTrader: (1)

Dunno if theres any interest, but just in case there a guy that sells gears on craigslist in the state I live in. Heres his link.
http://cleveland.craigslist.org/pts/3321727966.html
I havn't got my mine switched yet,but hopefully next year. Gonna go with 3.73. I won't be doing it myself. Hopefully by the time I am ready I am gonna have the guy put mine in. He says he can do it right on the car to so I don't have to take my rearend out so I guess thats a plus lol. Oh well figured I would share just in case someone was looking for some gears out there.

SR-71

BUYER BEWARE !!!
Double-check the fit before you put down any money or have the guy open up your axle. His ad clearly says, "10 bolt 7.5 gears - will fit all 7.5 10 bolt rears 1975-2004 S-10, malibu, Monte Carlo, grand Prix Camaro, Firebird..."

Uh.... no. He doesn't say anything about 7-5/8" (7.625").

If you're doing this for the '87 TA in your profile, and it has the original rear end, these won't fit. IIRC, '86 and newer F-bodies have the 7-5/8" carrier. I know my '88 does.

big gear head

7 1/2 and 7 5/8 gears will interchange. Most parts will interchange between these rear ends except in cases where the axle splines are different. The 7 1/2 and 7 5/8 both had 26 spline axles up to '90 and then it was upgraded to 28 splines. I have put 7 1/2 gears in rear ends that had 7 5/8 gears and I have put 7 5/8 gears in rear ends that had 7 1/2 gears.

SR-71

I can also tell you without any doubt that this is not absolutely true. Many aftermarket manufacturers have different part numbers for 7.5" and 7.625" carriers, even though the gear ratios are the same. In that case, they are making the ring gears with the exact inside diameter specified. If a ring gear is a true 7.5" inside diameter, it will NOT bolt onto a 7.625" carrier.

It is true that you can bolt a 7.625" ring gear onto a 7.5" carrier. In cases where the part numbers are the same for both carrier sizes, then the manufacturer is making the ring gears with 7.625" I.D.

But the real proof is in my own Firebird's rear end. I had to completely disassemble it in order to re-machine the Auburn posi in the carrier. That meant removing the ring gear. It had to be driven off of the carrier, following instructions I got from Auburn gear. To reinstall, it had to be pressed on. (I cheated by putting the ring gear in the oven and the carrier in the freezer.)

I measured the carrier and the ring gear, to be sure of what I had.-- In case I had to replace the carrier if I couldn't properly refinish the cones/sleeves. They both measured 7.625". There is NO WAY a true 7.5" ring gear could go in my rear end without replacing the carrier.

So what I told Slayze is true. Be sure the measurements are right. If the seller has "true" 7.5" ring gears, then they likely will not fit his '86, which should have a 7.625" carrier.

Also, he needs to know that if his present axle ratio is 3.08 or numerically lower, then he MAY have to replace the whole carrier assembly, not just the gears. The pinion depth is different between many carriers. Again, I learned this looking at replacement carriers for my own car, before I decided to try to re-machine the cones/sleeves.

I get the feeling that there is no hard truth across all 10-bolt combinations. But Slayze needs to be aware that it may not be the simple bolt-in that he's expecting.

big gear head

You have no idea what you are talking about. I have been building rear ends for 31 years and I owned a rear end shop for 15 years. I have build no telling how many 7.5 and 7.6 rear ends and I know for a fact that these gears will interchange. The difference that you are seeing in the differential part numbers is not because of 7.5 or 7.6, it is because they have 26 and 28 spline axles.

By the way, all ring gear are a press fit on the differential. If you get one that slips on easily then you have something wrong.

sofakingdom

iTrader: (1)

CARRIERS are different (on the INSIDE, where the small gears go); GEARS are not.

7.5" and 7.625" gears are COMPLETELY interchangeable in EVERY rear of EITHER size. In point of fact, the vast majority of mfrs don't even offer 7.5" gears; maybe NONE of them by now.

None of which has anything to do with "ratio" or "series"; both vintages of this model were available in both series.

Slayze

iTrader: (1)

From what my friends say the guy I linked to the ebay post knows what he is doing. I guess some of my friends have used him before. So I am gonna say that the guy probably knows what he is doing based on what some of my friends have said. I will also share an email he sent me.

(We really need to see what ratio you have now as you may need a spacer kit to install that gear on your current carrier. We also might have a thick set of 3.73 NEW which would also solve the carrier series break problem also.

IF you have 3.08 2.73 ish gears you will need a spacer plate or a 3 series carrier or a thick 3.73 ring and pinion set. If you have 3.23 3.42 in the rear you are GOOD to go with the 3.73 as is)

I just posted it thinking that if someone was looking for some gears (or even some place to get it done if your close) this might save them a few bucs is all. I wouldn't have posted it if I thought there was a chance the guy could be a fraud.

SR-71

Big Gear Head and I corresponded off-line, and he set me straight about the gears. I will admit when I am shown to be wrong.

Yes, they will all interchange. But they will not "fit" if you're putting 3.23 "and up" gears on a 3.08 "or lower" carrier. They'll bolt on, but you won't get the mesh right.

So half of what I said was correct, as Slayze just shared after talking to the shop in question. If he has 3.08 "or lower" gears (2 series carrier), then he will need a different carrier (3 series), a spacer ring, or "thick" gears.

zenish

What Is the Width of My 10-Bolt?
Approx. 57" from backing plate to backing plate and 62" from axle flange to axle flange.

JamesC[/QUOTE]

i measured the rear i just got from a 2000 camaro.its 64 15/16 inches from rotor outer surface to rotor outer surface.

JamesC

iTrader: (5)

i measured the rear i just got from a 2000 camaro.its 64 15/16 inches from rotor outer surface to rotor outer surface.[/QUOTE]

The FAQ is written for thirdgen 10-bolts. That said, thanks for posting. Someone may find the info useful.

JamesC

jacobglennsmith

Question for you gents, sorry to post on an old thread btw but i know i can get an answer from you all.

Swapping a 10 bolt from a 2000 Formula that had the LS1 and T-56.

Into my 1989 Iroc-Z that has a Borg Warner 9 bolt in it that's giving up.

I bought a 1LE proportioning valve. Will that combo work well?

I just didn't know if the prop valve would work right with the LS1 rear. I know it will with the LT1 rears though.

Thanks in advance guys!

TheRock86

hey guys im trying to do a rear lS1 swap on my 86 Iroc/z28. Ive tried looking but dont really fins any good info. I have a basic idea of what needs to be done but if any one could PM a link that shows most of what is involved it would truly be helpful thanks again guys

GaSS burner

please forgive me for posting on a very old thread but i cant find the help i need. I have a 91 camaro rs with 2.73 rear end gu2. so my question is that gm put limited slips in various models including the astro i believe 96 and up recieved 28 spline with 7.6 ring gears. also i believe its a eaton the problem im having is can i swap these limited slips and also are they all gov loc limited slips. im asking because you can get the entire rear end carrier for 28 bucks. including the ring and pinion gear and limited slip.

oldguy

My 91 z28 currently has 342 gears with the LB9/ T5 and g92 option . I am thinking about converting to 373 gears . I am wondering if it will give me a noticeable gain in low end torque and performance. The car doesn't see much highway travel, mostly around town. Comments would be appreciated.

mechanic58

You will be pleased with the 3.73s - they work great with that combo. However you really need to consider an aftermarket torque arm setup for the rear axle when you make this swap. The lower the gear the more stress on the torque arm. Every V8 third gen I ever had with a 3.73 or lower gear would tear the hell out of the trans mount. I recommend the Spohn units, they're very nice.

oldguy

Thanks for your response mechanic58 . your comments are appreciated

mcbitchman

here's the RPO Big Gear...

Irockthedrag

Is there anyway to tell how many spline an axle is without pulling the cover off or axles out? Any markings etc? I'm trying to go pick up a set of 28 splines and this guy has a bunch of rears and no tools to pull them. I don't want to make a 2 hr drive on just a chance.

big gear head

If you know what year it is then you can go by that. You need to pull them out anyway to check them for wear. You don't want to buy a set and then not be able to use them because they are worn.

johnhifi

So, question. I have 1992 B4c car that came with a 3.23 rear end. I picked up a 10 bolt 3.73 rear end from a earlier camaro that was supposedly a working unit. We swapped out the 1LE brakes from my car and placed them on the donor unit. It lasted less than a year when I got some excess noise from rear. Popped off the cover and piece had broken off from pinion that was saved by magnet. The gears inside are are Richmond's. The axels are 26 spline. Since the gears were replaced at one time I don't know what it originally came with. Sorry this is so wordy but my question is how do I know if this is a 2 or 3 carrier so I order the right parts. The number on the rear end housing is GM22522676.

big gear head

Get the Richmond number off of the ring gear and look it up. It will tell you if the gear was made for a 2 or 3 series differential.

johnhifi

The number on the ring gear is Richmond 80-0358-1 J <> 0 8620. Would pics help?

Numbah-1

I was wondering if the forth gen 10 bolts have the same gears as third gens?

big gear head

4th and 3rd gen gears will interchange. You still have the issue with 2 and 3 series differentials. You must have the correct series differential for the gear that you want to install.

sgeorges714

Question, what size are the bolts for the differential cover? I'm looking to replace mine.

JamesC

iTrader: (5)

Check the first page for that info.

JamesC

Romieo

Okay so this is my second 3rd gen but this one puzzles me. I raised ther of the car up so both wheels were off the ground. When I spun the right side wheel only that wheel spun. They did not go in opposite directions or the same just one spun. Can any one tell me why this is. Tried looking for the stamp on the axle but wasn’t able to find it either but it is a 10 bolt. Not a mechanic by any means but would love to know!

Chevy86 IROC-Z

iTrader: (17)

So what years and which vehicles would be best to pull a 10 bolt from? Will be hitting the junkyards soon. Thanks.

HeavyOlds

articwhiteZ

iTrader: (56)

let me just state..there is nothing you can do to get the 7.what ever.. to Get it to hold up to a set of slicks and 350hp..the pinon teeth will fall off every time... if you have to run that rear end.. never go over 350hp and slicks..stick to cheap tires and DD the car...stop putting money into the 7.5.. it will not hold up...just sayn...

Granny

Not sure I can agree with that. You might be surprised at how much power you could get thru a set of 7.xx gears with manual transmission and a proper hitting clutch.

Let's say you are putting 450ftlbs into a 700R4 with a 4500 converter and have traction-
...450ftlbs x 2 thru the torque converter x 3.06 1st gear = about 2750ftlbs to the pinion on the hit.
...450ftlbs thru a clutch that holds about 650ftlbs x 2.95 manual 1st gear = about 1918ftlbs to the pinion during a clutch dump.

The 7.5 is going to be able to process much more engine torque thru a manual trans than it can thru an automatic. Not that I would recommend it, but you could put 750ftlbs of engine torque thru a 900ftlb clutch hit and STILL put less hit on the 7.5's pinion teeth than 450ftlbs of engine torque hit thru a 700R4. Install a ClutchTamer to control the hit, even that 900ftlb clutch would no longer be a problem

Grant

articwhiteZ

iTrader: (56)

with a 700R4 and a 383 in the 90s I would brake 7.5 every weekend 5 or 6 sets in 2 summers...I could get them to last..if I came out of the hole like a slug 1.60+ 60 foot..they would last ..anything under 1.54..they fall apart.. my 383 was under 500hp..and.. used top name gear sets..one maker sent me 2 sets free as they had a life time warranty..
now this is with 4.10 gear ratio..and a auto foot braking the car. facts..keep your eng stock and have fun with your 7.5..you can not use slicks and 450hp.. I could brake them out of the hole and even at the top end...had all the good stuff in them...T/A covers.after market carriers.gear sets axles..the thing that brakes in them is the pinon..every time.. Fact!..when I put the 9" ford in my car I gave away the rear end that was in my car..GAVE IT AWAY!....the pinon is just to small to hold up to good power..spin the math how you like...400hp and slicks kiss it goodbuy..

the one way to never have to think about your 7.5 rear end...go with a 9"
400hp and street tires it might last...if it never hooks up...fun for some guys...

Granny

Sounds like none of your experience is with a proper hitting clutch.

Your 1.54 60' with an auto had the problem of the TC multiplying engine torque over 2x for the initial few tenths of a second, then it gradually settled down to a little over 1x before the shift. It wasn't the average torque applied over the 60' that killed your 7.5's, it was those first few tenths of a second or so when the stator was doubling your torque.

Manual trans packs more energy into the launch with higher launch rpm, but it's torque input/output is much more even over the 60' than an auto. Torque input from a manual is initially determined by the clutch's holding power (engine torque + inertia torque), but you lose that inertia torque when rpm drops far enough to synch with rising vehicle speed. At that sync point the clutch locks up and the engine starts to gain rpm, so torque input then drops to whatever the engine puts out at that particular rpm and accel rate. The net result is that you can apply a higher average torque over that 60' with a manual, without exceeding the strength of the pinion teeth.

Grant

articwhiteZ

iTrader: (56)

bolt some slicks on a car with 400hp and a standard.w/7,5..get them hot and sticky at the track and dump the clutch at 3500 4000rpm..you are going to take pinon teeth off...Fact!
math is math..and fact it fact... your not going to see a car with a 7.5 running 10s with a standard trans.. the pinon is just not up to it...not even if it had a rear pinon support... they make heavy duty parts for a reason.. they hold up longer..1310 u joints are not as strong as 1350 u joints..and a 7.5 is a weak rear end when you put power to it...they sell a lot of band aids for it...I just don't think your going to see any fast cars with a 7.5. I have had them come apart at the big end of the track at 120mph.. its not fun..its like rocks in a blender...and the trans was a non lock up...and when it comes apart it comes apart...brand new parts brake when you over power them..baby them when you have good power and you can get some life out of them... fact is ya don't need aftermarket parts in them... the stock parts will hold up just fine... ya want to make it stronger..= get rid of it! and put money into a 9" or something gm would put in a car with HP...

Granny

Whether or not you shuck pinion teeth with 400hp depends entirely on the hit, and the hit from a clutch is something that can be managed. 400hp matters little, same for 3500-4000 rpm.

Grant

articwhiteZ

iTrader: (56)

the point is..the pinon is to small to take any type of performance power... soft or hard...sad..but true..
ya want to play with the 7.5.. then don't put any power to it that matters for it to live...stick or auto...
if they did not fall apart.. guys would be running them...in all classes.. band aids are just that..a band aid..

Granny

My point is that the 7.5 can be taken much farther with a manual than you took it with an automatic. Managing the hit of the clutch is NOT a band aid, it's something relatively simple that's being done at very competitive levels. Championships have been won using my version of a clutch hit controller. It's also a concept that works well with the clutches that the typical thirdgen member probably already has.

Here's some answers that I provided to questions from NMRA/NMCA's Fastest Street Car Magazine, they wanted info about my ClutchTamer clutch hit controller after noticing it being used at their events...

• What inspired you to create the ClutchTamer?
I was looking to get the most power possible thru a Saginaw 4spd, which at the time was breaking at least once a month. I came up a simple plan to soften the hit of the clutch, it was based on a hydraulic screen door closer that I found at a local hardware store. I made a few modifications, named it the "Hillbilly Clutch Slipper", and it worked great. Back then it got that Saginaw down to 6.51 w/ a 1.45 60'. Pretty sure I could improve on that if I still had the Saginaw setup.

• How does the device work?
It's configured to allow the clutch pedal to be instantly released to a specific point within it's "sweet spot" zone. That sweet spot is the zone where the clutch hits/grabs just hard enough to get the car in motion as efficiently as possible. Any harder would result in spinning tires or breaking parts, any softer would slow reaction time and leave et on the table. As the pedal reaches that specific point within that zone, it's travel is instantly slowed by a hydraulic cylinder with the effect of extending the time spent within that zone. The goal is to give the car more time to gain speed before the clutch locks up, which helps make the car quicker by keeping rpm up higher where the engine can make more power.

• What are the benefits of dialing in the clutch hit and slip?
A properly dialed in ClutchTamer launch will hit softer than an automatic, but that softer hit lasts longer. Basically it takes a clutch dump launch that's too intense/violent that wastes a lot of energy, and transforms that launch by spreading the energy release over a longer time period where it can be harnessed more efficiently. That's what makes it so easy to launch on radials when the hit is controlled by a ClutchTamer. That softer launch also makes the car less sensitive to chassis/shock adjustments, so less likely to need expensive shocks to control that softer hit.
The ability to dial in the hit also makes it possible to launch from pretty much any rpm you want to. Launch rpm is basically stored energy, and the engine has to make the energy that it takes to spin up that rotating assy. A slip controlled clutch allows spinning it up much higher prior to the start, which makes more power available to accelerate the car when the clocks are running.
Another benefit is there's no need for low air pressures to help absorb the hit with the ClutchTamer, many racers using the unit have their slicks up to 20psi or more. In the end, you get a consistent dead hook launch without a bog that's quicker and far less likely to break parts.

• How difficult is it to arrive at the ideal adjustment?
It's pretty easy really. If you are dialing it in at the track, set the 'Tamer's outer "delay" adjustment to 4 turns or so, pick a launch rpm near your HP peak, and make a hit. Abort the hit if the clutch is obviously slipping too much, but if the hit was fair and the tires didn't spin, add 1 turn clockwise to the 'Tamer's inner "hit" dial and make another hit. Keep adding 1 turn of hit per pass until the 60's stop improving, fine tune from there.
Some aspects of ClutchTamer tuning can be counter-intuitive, like adding delay when a clutch appears to be slipping too much already. This is because low delay settings allow the pedal to pass too quickly thru the sweet spot zone, which leads to an initial hit setting that's too soft. When you release the pedal, you want it to instantly hit deep within that sweet spot zone to get a nice crisp hit, but that crisp hit will require a lot of delay to keep it from leaving the zone prematurely.

• Can a device this simple really make high-powered manual cars faster?
Yes, in the same way that a looser "less efficient" torque converter can make an automatic car quicker. Controlled clutch slip does pretty much the same thing by effectively raising the engine's average hp/rpm over the duration of the run. A slipping clutch is a less efficient coupler, but the energy that's absorbed by the clutch while it's slipping is more than offset by a much larger HP gain. This is possible because the engine can operate at a higher average rpm where it's much happier and makes more power.
There's also no need an extra deep 1st gear to help induce/control wheelspin, as ClutchTamer launches are basically dead hook. Much like an automatic car can respond to less 1st gear ratio as a way to help keep the tires stuck, a less aggressive 1st gear ratio in a manual box also hits softer and has that same side benefit of more time spent in the gear with the most mechanical advantage. Softer hit, more duration. Less aggressive 1st gear ratio also means a closer split, which translates to less rpm drop after the gear change. The net result is that average rpm and power production get bumped up a little during the gear change.

• Is there a limit to its efficacy based on the clutch design, etc?
Yes, there are limits, but you don't need a special clutch to start enjoying some ClutchTamer benefits. Even a stock organic clutch can typically be slipped a little longer, which increases average hp and reduces bog. Ceramic friction material is a better choice for controlled slip than organic, due to it's tolerance for higher operating temperatures. I typically stay away from Kevlar, which can be easily damaged. Carbon/Carbon has a really high temp tolerance, but low overall mass means carbon reaches critical temp much quicker than you might think.
Super light weight clutches may have a high torque capacity, but their lack of thermal capacity causes them to reach their critical temp pretty quickly. That in turn, limits how far you can go with exploiting more clutch slip for bigger power gains.
For the most potential for ET improvement, I generally prefer lite weight steel flywheels, steel or iron pressure rings, and sintered iron friction material. Basically I like to have enough clutch to be able to slip for about 1.5 seconds WOT without reaching critical temps. If you have synchros, a puck style iron disc is a good choice, as it can tolerate hi temps while it's lighter weight allows for higher rpm shift points. My personal ride is faceplated, which allows me to get away with using a heavy full face sintered iron disc. That's an advantage for some of the zero prep surfaces that the car occasionally runs on, as the extra mass allows the option to launch in 2nd gear if a surface is really bad.

• Is there any downside to using the device, say on a street/strip vehicle?
None at all. Pedal release rates during casual driving is typically a lot slower than a slip controlled drag strip launch, so the driver still has full control over feathering of the clutch pedal for a smooth start.

• Does using the device mandate a different driving style?
Not for casual driving, just drive it like you did before. You may notice that the clutch pedal takes longer to return to the top when released, but other than that you probably won't even notice that it's there.
For launching at the drag strip, releasing the clutch pedal from a properly adjusted pedal stop is a must for consistency.

• What do racers report after using the device?
It's a foreign concept to most seasoned racers, as they've been racing for years and have a hard time believing something so simple could make such a difference. In my opinion NMRA Factory Stock racer Dan Ryntz says it best- "don't knock it 'til you tried it!" Pretty sure he took home over 20k this year in "big checks" on his way to the Factory Stock championship!

• What racers/combos are not a good fit for the tamer?
Something like a short track oval car where moi is everything, that would not be a good fit. You can't slip those clutches much without causing damage, it's not even recommended to use those clutches to load the car on the trailer!

articwhiteZ

iTrader: (56)

keep the car bone stock.. no prob...they are not fast cars to start with.. slip your clutch all ya want..anyway ya want...ya want speed and power?. Then upgrade.. if not. band aid it all ya want...Im telling you what not to waste your money on upgrade parts for the 7.5 rear end..when the pinon is the part that FAILS! big time..

Granny

Sounds like you found your limit for the 7.5 at 350hp with an automatic and moved on. I'm pretty sure a manual can do a lot better than that.

Grant