I have an 85 camaro with the 10 bolt, but I want to use 4th gen internals. I bought a 7 5/8 posi carrier for 28 spline axles and bought some 4.10 gears off my buddy from his 4th gen. My question is can use some 28 spline axles from a 91-92 camaro and make this work?

 

Yes.

Is the posi that you bought a 2 series or a 3 series? If you have a 2 series then you will need the thick 4.10 gears to make it work. If you have a 3 series then the regular 4.10 is what you need. Be sure to get a good installation kit. This will make the assembly much easier. DTS and Tom's Differentials have the best kits.

 

this is what i bought. I'm slowly learning. what series would this be?
http://cgi.ebay.com/ebaymotors/ws/eB...m=370046993461

 

That would be a 3 series

90-92 28 spline third gen axles will work providing you can find some. It's easier and better to just buy aftermarket 28 spline axles which will be much stronger than the factory ones.

 

That's a Governor Lock from an S10 truck, not a Camaro. The 4th gen Camaros used a Torsen differential. This Governor Lock will likely break if you use it rough. These are designed for stock truck applications, not high performance use. It will work in your Camaro, for a little while.

 

i know that the 4th gen is 4 inches wider than the 3rd gen. i dont know if the extra 2 inches in each axel or not, but it is 4 inches wider.

and this is to BIG. how do you know it is not as represented? what do we look for to makre sure we dont buy the wrong thing next time too? im going to keep the picture so i can look to see what it is you see, so i can recognize it next time. thanks for the information.

 

Here are some pictures that I have posted. They have brief descriptions with them to help identify what they are. If you have questions send me an email and I'll try to reply as soon as possible. biggearhead@bellsouth.net
http://rides.webshots.com/album/55410292AnMJrE

The 4th gen axles are longer.

 

Thanks for all the good info. I figured I'd have to go easy on this rear end and save up for a big boy in the mean time, thats why I was pushing for the 7 5/8 and I'll use a stud girdle and see if that gets me a little further down the road. Any good ideas one where to find aftermarket axles? thanks again guys

 

Moser makes good axles.

 

Other than custom ordering them, there's probably a few places that sell direct replacement aftermarket axles.

http://www.tomsdifferentials.com is one of them. KAC7-A7 is third gen 28 spline axles. They're designed for 90-92 third gens but all third gen 10 bolt axles are the same length. As long as you're using a 28 spline carrier, they'll fit all 82-92 third gen 10 bolt housings. I'm not sure what the current price is but they were $125 each a few years ago.

 

Just for fun, what would be an ideal rear end of choice for you if you planned on pushin 500 horse or so and wanted to keep the car streetable. Would a 12 bolt be enough? or is the 9" the best way to go. I heard that currie was pretty good too and they sell the whole kit in summit I believe. Any thoughts people?
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thanks for that, I'll check into it.

 

The Moser 12 bolt is more than enough. It is lighter than the 9 inch and it allows a little more power to reach the wheels. It is also cheaper than the 9 inch.

 

The power loss between a 9" and a 12 bolt won't be noticed with a low HP engine. They are both roughly the same price. The choice is yours as to exactly what you want to put under the car. If you're going with a 9", use 31 spline axles. The 28 spline axles are for stock powered cars. 12 bolts use 30 spline axles.

12 bolt diffs are 8.875" ring gear so it's not much smaller than a 9". The 9" has a lower set pinion which is why it uses up slightly more power. The carrier (spool, posi etc) that you intend to use in the 9" can use any gear ratio. There's no series like the GM diffs. The 9" can me made much lighter by using an aluminum center section.

There are a lot of pros and cons to each diff. One isn't better than the other. It just comes down to personal choice and exactly what you want to do with it.

As a drag racer, I prefer the 9". Parts are plentiful and it's easy to pull out the center section and set the gears up on a bench. I just upgraded to a Moser bolt through center section, aluminum Daytona pinion support and aluminum spool. My whole diff including the drum brakes probably only weighs just over 100 pounds. I was starting to get a little hard on the factory C7AW-E cases.

 

9 inch has a better gear selection and if you had two center sections with different ratios its fairly quick to change

 

I wouldn't say fairly quick but typically, it would take 60-90 minutes to change it out depending on your skills.

Jack car up and put on jack stands
Remove wheels, drums or caliper/rotor, unbolt and pull axles
Disconnect driveshaft
On a third gen with torque arm, remove torque arm and make sure diff doesn't roll back.
If the diff has a drain plug, drain oil
Unbolt and remove center section. If no drain plug, catch oil as center section is popped out of housing.

My housing has a drain plug at the bottom and a large fill plug at the top rear. I only use the fill plug on the side of the center section to tell me if the diff is full.

 

"Fairly quick" Changing center section vs. setting up a new set of gears in a 10 bolt or any other diff where you have to remove carrier. Never under estimate the power of " I gota get this done".Now grant it, my head is still stuck in my round track days where if you where at the track and had the wrong gears in the car or you broke something.......you got it changed in 45 minute. But I realize thats a little different than " I think I'll change my gears this afternoon"

 

Not trying to start an argument, just pointing out some facts.

To be able to quickly change the gears in a 9 inch you must purchase enough parts to build 2 complete chunks. That means 2 cases, 2 pinion housings, 2 differentials, 2 gear sets, 2 bearings sets and 2 yokes. That is 2 times the money. This is assuming that you want to use new parts. If you are building junk yard rear ends then that is different. Now that you have all of these parts you must spend twice as much time setting up both cases.

If you spend the same time setting up 2 sets of gears for your 12 bolt then you can change gears in it almost as quick. Use a solid pinion spacer so that you don't have to mess with setting the bearing preload over again. Use a seperate set of shims for each set of gears and keep up with their locations so that you don't have to set the pinion depth and backlash over each time that you change the gears. This way you only have to buy 2 sets of gears and shims, and not all of those other parts. Much cheaper than the 9 inch. If you want to run a spool with one set of gears and a posi with the other set then you will need to buy those, but you still don't have to get another case, pinion housing and yoke.

With the 9 inch or 12 bolt you still have to remove the wheels, brakes, axles and drain the oil, so the time spent on that won't change.

 

6 of one, half a dozen of the other.......

 

You are right, it's just a matter of preference. I just wanted to show that the 9 inch isn't the only way to go if you want to be able to swap the gears from time to time. It's a job eather way you go.