My 91 RS originally came with the typical 2.73 open, drum brake rear end. I bought a 3.42 disk brake posi out of a wrecked 2000 SS and am installing it this weeked. The rear I bought was a 4 channel rear end meaning it had traction control and therefore no T block.

To get around this issue I took the T block from my 3rd gen rear and attempted to use it. The passenger side stock 4th gen hard line threaded right into my T block which I was able to bolt in the stock location as it was on the 3rd gen rear. However, for whatever reason, the driver side stock 4th gen hard line had a bigger fitting so it would not thread into the T block. I took the driver side hard line off my 3rd gen rear and was able to use it to go from the T block to the driver side caliper on the 4th gen rear. The 3rd gen hard lines are longer than the 4th gen, despite the fact that the 4th gen rear is wider. I simply wrapped it once around the axle like so. Be careful not to wrap it in such a way that it will interfere with the shocks or sway bar.



After this the only issue will be the emergency brake cables, which I haven't solved yet. I know there are a number of solutions and I will post up what I decide to do. Here are some more pics of the swap:


Before, something we all know and hate...




During. BMR lower control arms, BMR panhard, Spohn subframe connectors, Koni Red shocks, 3" custom mandrel bent exhaust with a Flowmaster super 40. I did all this awhile ago before I installed the rear.



Got it all mounted up. I LOVE the look of those disk brakes on a third gen! Pardon the rust though








Here are the wheels. Keep in mind the suspension is hanging.

 

going on 2 days and no one has said anything?

i know people swap these things in all the time, but i enjoyed reading the write up.

got any pics from the rear with in on the deck? how wide are those tires?

 

The tire is exactly even with the outermost portion of the fender flare. Keep in mind 4th gen rims with a 4th gen rear fix the issue...

 

Are the 4th gen rears stronger than most 3rd gen rears ?? Hence the reason for the swap.

 

I swapped mine in for the bigger brakes and to have an aftermarket parts selection (originally 9 bolt) and it is definately strong enough to handle anything I'll be throwing at it. I also really like the stance of it with the wide track rear.

 

no, they are the same strength, just wider (the 9 bolt that comes on some 3rd gens is stronger though).
Most people swap them out so that they can run the 4th gen offset wheels with no spacers.

 

I did it because for $260 I went from drum 2.73 open diff to a disc 3.42 posi. How can you pass on that?

 

hows that rear holding up? im glad i searched for this cuz i just bought a 2002 ss rear and i knew i was gona have issues with the break lines. thats a pretty crafty way or getting aound the line problem. i plan on doing the swap this weekend as long as the weather holds up.

Note to others... the search button can be your best friend!

 

I'm going to use this: http://flynbye.com/catalog/i193.html. The rear I got is the 4 channel one with TCS.
And this will solve the e-brake issue: http://flynbye.com/catalog/i153.html

 

Help me out with the 4 channel issue. Is it simply an electrical connection left unplugged? Or is it a brake fluid line that needs capped? What is required to use the traction control rear ends?

 

whats funny is the 4th gen guys who get a little more serious end up swapping to our width or even shorter if the mini tub

 

I see you started with a drum rear, what did you do for the proportioning valve? sorry to bring up the old thread currently about to conquer this swap due to a dead fuel pump and original saggy springs.........