I figured the car has a lot of miles on it and while i got the tranny out for a rebuild ill change the rear end fluid. Went well (didnt GM make anything easy on these cars, lol) After cleaning off the mating surfaces and wiping everything clean i figured id double check my gear ratio on the edge of the ring gear. The car was bone stock when i got it so i figured that it had the same 3.23 gears that the data plate said it had. Well low and behold i find out that it has 3.42 gears in it . Could this be a factory giggy or did someone simply blow a rearend up early in life and have it replaced with a 6 speed rear end. The previous owners were all daily driver people and the gears were factory gm gears. What do you think? Thanks Prorac1

 

Doubt the factory screwed up. How do you know they're 3.42s?

 

The factory (or gear manufacturer) stamps it into the side of the ring gear. p.s once i get my tranny back in i still need to get a hold of you for some programing. Thanks for the reply. Prorac1

 

Hmm...aren't your speedo/shift points off, or do you think the programming has been changed as well?

 

My speedo has always been about 2 mph off, but that was my next question, how far would it be off for that little differance in gear ratio.

 

Hmmm, I was under the impression that it would be more than 2 mph off. Well, depends on what MPH you're considering.

3.42/3.23 = 1.0588

So an actual 100 MPH will show as (100 MPH * 1.0588) 106 MPH
50 MPH ~ 53 MPH

 

Are you sure you looked at it right? You would not be the first person to post that they had 3.42s when they were supposed to have 3.23s. The ratio is not stamped on the factory gears, it is the number of teeth in the set. Some people see the "13-42" and think they have 3.42s. Just throwing out the possibility.

 

If you've got an A4, I'm betting 3.23's

BadRag

 

I was under the impression that only A4 cars with the 1(PRND21) spot on their gear selectors had 3.23s that all others with just the 2 (PRND2) had some other gear like 2.73s or something.Is this wrong?

 

No. You are correct.
Performance axle ratio was 3.23 all other autos had 2.73.

 

i bet that shoe box is right. Cause the letters i saw looked just like the pic he has. Oops, my mistake. Thanks for clearing that up shoe box. Prorac1