i have a 88 trans am and it should be spinning posi and it dont just the right back wheel spins unless i turn left then the left wheel will spin and it will spin fast but no posi why is this and what can i do to fix this or is there a rearend i could put in that would make it spin posi at the junkyard here they sell rearends for $25 i need the make and model of the car that u list.

 

lol


well its not gonna spin posi unless it is a posi rear

does it have G80 listed on the spid label in the car ?

not many do

any 82-up camaro or firebird axle will bolt under yours even after 92

good luck

 

Even if you have a G80 option the posi unti could be toast, or an open rear could have been swapped under the car at some point in the past by a previous owner.

If you pull the cover off the rear you can see if it's a posi rear. There will be springs inside the diff (you can see them through a window in the casting), where and open diff will just have gears and the cross pin.

If it is a posi and it just doesn't work then you have one of two courses of action. Either rebuild the unit or replace it. Auburn and Eaton both make good aftermarket units for the 3rd gen (provided that it's a 10-bolt, and not the 9-bolt (count the bolts that hold te cover on the rear)).

If you grab a junkyard rear pull the cover and check to verify that it has a posi. This is still no guarantee that the posi in the junkyard rear isn't burned up too, or that it will need axels or other expensive parts. Unless your rear is totally fragged I'm always a fan of fixing what you've got rather than getting into a new series of unknown problems.

 

if its a 9 bolt then you should have posi... if it isnt working like mine, you probly need shims to add to the posi to get the cones to grip better. the cones are probly worn down, and shimming could help provided its not too far gone

jack up one side of the car leaving one of the rear wheels on the ground. and take a torque wrench and spin one lugnut to turn the wheel. if it takes less than 30lb ft then its worn out posi. whatever torque it takes is a percentage of how far gone the posi is. for instance... if it takes 15 lbft to turn the wheel, then 15/30 is .5 or 50 % gone. if its low like that, time to replace

 

Even though it is a TA, it may very well just not have a posi from the factory. I have an 85 Z28 that is a one-wheel-peel with drum brakes. LG4 engine too. Sad if you ask me...My RS came with the same rear end and a more powerful engine.

 

so if i went to the junkyard what car could a pull a posi rear end out of?

 

Anything with a 7.5" 10-bolt and the right axel splines. I would verify axel spline count first. It will be either 26 or 28. 4x4 S-10 trucks are a good place to look, because a lot of them had posi rears. 3rd and 4th gen F-cars (though 4th gens only work if you've got 28 spline axels) are the next place to check.

For the same price you can probably just buy the rebuild parts from Randy's Ring & Pinion. Then you know the unit is good and that it'll fit.

 

and how much is that and where do i find it or could i just use a v6 camaro rear or a specific year and model that u know would deffinatly have one? i kind of dont want to search all day lookin in this weather.

 

Just go buy a complete 4th gen rear end. It is a direct bolt up.

 

it also sticks out about 3 ins (3-4 in longer in total length). Looks realy bad having the rears sticking out this far to me but, that's just my opinion...

 

I saw a 91 RS with a 4th gen rear and ZR1's, I did not think it looked that bad. But like you said, it is all opinion.

 

The ZR1 wheels have the same backspacing as 4th gen wheels, so using those wheels and the 4th gen rear in a 3rd gen will still keep the tires inside the wheel wells. If you try to use your 3rd gen wheels they will stick out past the wheel lips and look like something from the 70s.

 

oh... that would explain why they looked ok then.

 

In my experience if I turn left then the right wheel will spin.

Seriously. Have you pulled the cover to check if there's a posi in there? Why do you think you have one? You might be able to save yourself an assload of time if you already have one but it's burnt out. Then you just rebuild it. Unless it's an Auburn, of course...