nuggie

okay so I got a rear out of an 85 trans am apparently the trouble year when they change from the 7.5 to 7.625 found that out after I had installed the gears and completely destroyed a spool from not have thrush washers in there so cleaned the carrier and install a new spool Yukon I think this time with the thrush washers. but it's recently begun clanking just like the previous one did before it blew apart. I just don't know what to do the only 7.625 spool they make is for a different axle spline number I think 30 instead of 28, but from what I was reading on here the axle shafts out of the 91 though 30 spline are a different diameter. so what would you guy suggest I don't reallay want to take the whole carrier out and have to reshim the pinion and carrier to get the correct play and tooth pattern again. What would you guys reqamend? I was also considering just welding the spool end pieces to the carrier that way less stress is put on the cross pin block?

AlkyIROC

Theres nothing internally different between a 7.5" and a 7.625" diff except the diameter of the ring gear.

I've never seen a full spool for this diff. Only a mini spool. These diffs use 26 spline axles. In 1990, GM upgraded to 28 spline.

Changing the side gears from 26 spline to 28 spline will not allow you to use 28 spline axles. The larger axles will not fit through the hole in the carrier. To use 28 spline axles, either aftermarket or from a 90-92 f-body, you need a carrier (posi, open etc) designed to use them.

big gear head

If you are trying to use a mini spool on the street then forget it. It won't hold up. You will destroy one after another. They are designed for dirt track use, not street or drag racing. They won't handle the constant thrashing from turning corners on the street.


If you weld it then you better be ready to replace the whole rear end when something breaks again. You will not be able to get the axles out, which means you will not be able to get anything else out.


Do it right. Get a limited slip differential and make your car drive better and much safer.

nuggie

no the 7.5 and 7.625 have the same ring gear different spider gears from what I have read Pontiac switched to the 7.625 in 85 but kept the axle spline count the same chevy waited until 90 and then switched to the 28 spline. and why don't they just make a full spool for these rear ends? My brother and dad both ran mini spools in their Novas both the 10 bolt 7.5 rear and they both have never had a problem even running a 454 and 4.88 gears. why doesn't my set up work? I would much rather have a true locked rear end then LSD paying I had an auburn in there when I got the car if you jacked it up both tires would spin but on the ground doing a burn out it was a one wheel wonder. but if I did just switch to a 7.5 carrier or even and LSD carrier would I have to reshim the pinion?

nuggie

did some more research are the stock zexcels out of a 98 and new camaro and good how often the wear out/ are they rebuild-able

Night rider327

iTrader: (13)

Stick a locker in it and get best of both worlds. I have used the power trax lock rite for years

big gear head

The Lock Right is a good option as long as you have a good differential case. Many times people have done a lot of one wheel burnouts in these cars and it has worn out the inside of the differential case. When this happens the Lock Right will have too much clearance in it and it won't lock up. I've had a Lock Right in my truck for 18 years and put about 190,000 miles on it and it still works great.


The Auburn is the worst LSD that you can get. I can understand why it gave you a bad opinion of LSDs all together, but others work much better. The Eaton Posi Yukon Dura Grip, Power Trax Grip LS and Eaton Truetrac are much better. The Torsen only works with 28 spline axles, so you would have to upgrade to use it.


You do not have to shim the pinion when changing the differential. You do have to shim the backlash and bearing preload.

nuggie

never heard of the lock right I will have to do more research on that. I dont really have a problem shiming the carrier for patteren agian that was fairly easy and looks possbile while the axle is installed as the pinion would be a pain

nuggie

looking into the lock right I love the set up pretty much fits in just like a spool the only problem as someone else mentioned above is when my first spool broke it took some chunks out of the carrier nothing to gnarly but still noticeable you think it would work? It's about the same price as the other LSD options though. they do however have the 7.625 option with the 26 spline axles I think I may try that, unless you guys think it would be better to try something else

Night rider327

iTrader: (13)

I can't say about the damage to your carrier but I'll give you my opinion on the lock right.

I bought one for my 1988 camaro (7.625", 26 spline axles) in early 2005
Late 2007 after 2.5 years of daily driving and every weekend at the track I broke the ring gear. No fault of the locker.
Swapped parts over to a parts car rear end and put it in mine. Broke pinion on that rear shortly afterwards. Again no fault of the locker.

Gave my dad the power trax lock right for his firebird and I bought a ford 9" for my car.

I was running 11.40's when using the lock right. My dad has been using the same locker in his since then even behind a twin T3 turbo charged 337 small block and working fine.

When using it on the streets it has a slight learning curve. As you throttle up or down in a curve or turn the locker will lock up and you get a rear end wiggle to your car.

As you turn into a road, parking space, etc it does click like a ratchet and sometimes you get a little bucking with it.

Like I said though I drove it daily for over 2 years (even have a locker.. Detroit locker in my ford 9") and my dad has used the lock right daily driving since early 2008.

So it pretty much has been in daily use for 10 years.

I really have only good things to say about the lock right. It does the job and does it well. Very strong unit, Very even power placement to both axles.

The only bad thing I can think of is how much of a PITA it is to remove vs. install. The thing goes right in. Very easy to install. I would say an hour start to finish.

Getting it back out seemed much hard when I removed it from the 1st broke rear end, then again from second broke one to goes into my dad's. IIRC it took me like 3 hours to get the darn thing out. Couldnt get the little pins and springs out

nuggie

interesting that sounds like the route I may go, so I know you said he still uses it but does it still work like actually lock up? I mean its gotta wear out eventually. Whats the warrentee on it? I don't mind giving it a try but I don't wanna be out 400 bucks if for some reason breaks apart like everything else

big gear head

The Lock Right is pretty tough. I've only seen one that didn't hold up to some hard use. I had one that broke because the rear end housing was bent pretty bad. The most common problem that I have had with them was with worn out differential cases from people doing one wheel burnouts before installing the Lock Right.

AlkyIROC

Highly unlikely. A Nova would have had an 8.2 or more probably, an 8.5. They even had a factory option for a 12 bolt. The Nova did not come with the tiny 7.5" diff.

Even though they are all considered 10 bolt diffs, the 7.5/7.625, 8.2 and 8.5" are all different and do not have interchangeable parts.

Night rider327

iTrader: (13)

Yeah my old lock right is still functioning like new in my dad's car. Locks and un locks just like it did the day it was installed.

big gear head

Starting in '76 GM put the 7.5 rear end in the 6 cylinder Nova.


The '62 and '63 Chevy II used the old drop out 8.2 rear end. From '64 through '71 the standard Chevy II and Nova got the 8.2 10 bolt. From '65 to '70 the 12 bolt was used in the high performance Nova. In '72 the 8.5 10 bolt was used in all Novas and other X body GM cars. The V8 cars continued to use the 8.5 through '79, but in '76 the 6 cylinder cars got the small 7.5 10 bolt.

nuggie

I think his was factory v8 but it's probably my mistake anyways why would a mini spool work in those other size 10 bolts and not the 7.5/7.625

nuggie

well I ordered my new lock right locker today hopeful you guys didn't steer me wrong. what is the break in process for these? cuse the drag strip opens up in 2 weeks and wanna have it all broke in and solid before I hit the track, I am really excited about the LSD instead of a full locker I wanna start doing some time attack and autocross this season, I was already using the full synthetic gear grease for the rear do I need to add that special friction stuff? I didn't need the c clip elimation kit did I? I forgot to ask about that. Also do I have to worry about those horror stories of broken axles shafts that I have hear about

big gear head

Crap, you didn't say anything about auto cross before. The locker isn't going to be great for that. You would need a Truetrac or Torsen for that. You need to choose the correct differential for the use of the car. A locker is great for drag racing, but not good for auto cross.


The mini spool was going to be even worse for auto cross.


No need for c clip eliminators. Any good gear oil is fine. No need for additive with the locker. No break in.

nuggie

it's not like autocross is going to be my sport of choice...this season, but I want to try it out. plus I still have that 91 rear end that I gatta change the carrier out in anyways probably do that in one of those options getting excited it should be here tomorrow and I got my autoprom today

AlkyIROC

I've never seen a c-clip eliminator for a 7.5" diff but if you have rear disk brakes, that will also keep the axle from coming out if you break the c-clip tab or an axle. The caliper over the rotor will prevent the axle from coming out. C-clip eliminators are only really required when using drum brakes.

nuggie

cool cant wait to get it in tomorrow already got the rear tore apart and ready also took a video of how sloppy the mini spool was and I barely had it in a month and only drove it on the weekends pretty much, how hard is it to install?

Night rider327

iTrader: (13)

Pretty simple install. Should take about 30 min or so being you already have the rear took apart.

nuggie

got it installed but it took me way more than 30 min lol more like 3 hours just because I keep second guessing what I had read and tracking down those friggen spring. feels a Whole lot more solid then the spool and I only had to use the normal two thrush washers instead of the four I was using to make the spool "work"

big gear head

Great. This should be much better than what you had and I hope it lasts a long time.