i am trying to fit a 4th gen rear end into my 3rd gen. I havent came across the rear end yet but when i do what will i need? Will i need 4th gen driveshaft, shocks, springs, etc??? what is exactly needed?? what parts can be sacrificed off my 3rd gen to use on my 4th rear end??? Also, what 4th gen rear end should i look for??? I want the 3.42 gears an i heard they only come in the 6speeds.... a little info would help. What year donor should i look for?? i heard 98-02 would be best but there is alot of 94-97 going in that i see. let me know. thanks

 

Try a few searches. This gets asked on a weekly basis. You can use a 4th gen rear while retaining all of your current 3rd gen stuff. They are basically the same rear. They are 2" wider per side and will make your stock wheels stick out. You may weant to look into new wheels or use a set of 4th gen /vette wheels with spacers up front.

LT1 and LS1 A4 cars gad a 3.23 rear and T56 cars had a 3.42. people prefer the LS1 rear because of the brakes that usualy come with it. You can also use a V6 rear but not all of them were posi.

That should help you get started on your search.

EDIT: I forgot to mention that A4 4th gens could also come with a lame 2.73.

 

so i can use same drivesahft???? same shocks, springs, sway bar etc.?? i did do a search and couldnt find anything that answered my question. I will find a 6 speed rear end that had 3.42 in them. thats one question out of the way. now what about my others???

 

Maybe I wasn't clear enough with that.

By stuff I mean shocks, springs, sway bars, ect ect. Keep searching your answers are already there.

 

ok what about an answer now and save me time???

 

EVERYthing!! All you need is the 4th gen rear. Shocks, sway bar, torque arm, LCA's, etc. all work with it.

If you have a drum rear, then you might have to change some brake parts, but otherwise it bolts right in.

But, you will need 4th gen wheels. Like he said above, the 4th gen rear is 2" wider, and your tires will stick out or/and rub the 1/4 lip.

 

All the answers are there if you search, as far as time if you don't have the time to find out the information you need then maybe you shouldn't try to do the swap as it takes up to 2 days to drop the old rear and put in the new one. Me personally I'm gonna change all the seals and bushings on the 4th gen rear before it goes in, but that's up to you if you wanna change that stuff down the road while it's in the car and more difficult to work on.

 

What about my time? By the time I read this post it was a day or so later. You could have found your info by then. We are talking about minutes worth of effort. We can't have that many redundent posts. The search is your friend, trust me.

 

everything fits as a direct swap except:

if you have a traction control car rear, it has two brakelines instead of one.

the ebrake needs a bracket made... either drive without a ebrake, or make a simple bracket to hold the cables, and have a muffler shop tack weld them to the floorpan.

 

thanks guys. going to pick up one this weekend. takes 2 days to drop and replace a rear end?? took me 45 minutes with 2 jackstands and a jack to drop my old one. I had torches and impact wrenches though. I already replaced all the bushings and bolts last time i swapped it. It will be even easier to drop it now. time - - - 5 hours tops to do the swap - thats if its all a swap

 

theres actually a tech article on how to do it on this site. In there I'm pretty sure it said 2 days.

 

I did this swap last night with a friend in about 5 hours. It is very straight forward, and well worth it. Good luck
FBird

 

thank you - like i said - 5 hours. how do people make a 2 day project out of this??? whatever. i bought my 4th gen rear end out of a 99 camaro SS with 3.42 in it. bought it for 100... lol .. local guy around here. rear end still was under warrenty - gears swapped out about a month ago (replaced under warrenty) Rear end is tight and clean. Anyways, it doesnt have rotors, calipers, backing plates, etc. I was wondering if i could get away with no rear brakes period or can my 9 bolt brake parts be swapped over?

 

i have swaped out axle a few times and the last time it took my barely over two hours, it really easy after you do 1 or 2 or them

 

Your 9-bolt brakes will NOT work. I just did this. Your rotors won't fit on the 10-bolt axles and the backing plate holes won't line up. Go to LS1.com and cruise the classifieds for someone parting out a ls1 car. That is what I did. I got everything I needed for $200. You can also check EBay, but the average is over $200. Good luck,
FBird

 

A couple of shots of 4th gen rears and 3rd gen wheels,
Stock 0 offset wheels,


16mm offset GTA rear wheel,

 

Hey, I know you.

Looks like I may also be doing this swap. I'll probably end up hitting you up sometime on Drag or here for some pointers? Searching around here now from any info, but I'm pretty sure my rear-end is done for. It's acting like it has detroit lockers in it right now, I can't hardly turn with it CLANKing horribly!

So on this topic, it's not even worth swapping a 3rd gen rear-end back in, is it? For the money, might as well go with 4th gen? Especially since I alraedy have a set of 4th gen wheels that I was waiting to buy spacers for.

Or should I worry about the little details abotu the swap?

 

If you are running 4th gen wheels, go with the 4th gen rear end.

 

Yay.

Bought a 94 MT rear, so I'm assuming that's the 3.73 gear ratio? I know I could research it, but I'm more interested in getting the car on the road. I'm happy about my decision, but now I'm thinking I might go ahead and spend a little more and do the driveshaft as well. I'm about to spend some time wiht the magic search function, but maybe someone will breeze through and tell me that any LS1 aluminum driveshaft will fit my application, or what specifically I need to look for.


One of my students has an '88 with 350/A4 and he just did the driveshaft swap and felt a good gain, so I'm all about it now. But I'm not sure what all it involved. Time to search!

 

MT rears are 3.42 from 94-02. 93 had 2.73 and 3.23 rears and there were 2 versions of the T56 depending on the rear that the car got.

The driveshafts swap over just fine, nothing special to do.