Gear ratio question

[95Grand-Am]

I have a 1995 Grand AM with a 3100 and a 4T60-E that I think has 3.33 final drive ratio. Some one told me that GM put 2.97 in them. Does anyone know what is should have or how I can tell? Thank you for your help.

[torq455]

yours should be the 3.33. someone might be thinking about the 3.3 in the older years?

[95Grand-Am]

Thanks TORQ455.

[Azrael]

The differential in your car gives a 3.33 ratio. But because of the overdriven chaindrive deep in the transmission the overall FDR drops to 2.97.

[95Grand-Am]

The Grand-am is an N-body? In the Idenifiation chart it shows that it has a 3.29 final drive and a over driven chain drive giving a over all of 2.93. But I have read in other place that it has a straight through drive chain and 3.33 final ratio? Is there a way that I can tell for sure what it has?

[3400-95-Modified]

I'll check my book when I get home. IIRC they drive chain setup is overdriven, so yeah you would have 2.93

*Edit
This should answer your question.

http://dtcc.cz28.com/transmission/index.htm

L/N body is the same 2.93 FDR...

[95Grand-Am]

Thanks 3400-95-modified, you saved me from making a big mistake. The code on my transmission is 5WFW which is a 2.93. I need to add about 4 tenths of gear to my race car. Can I put a transmission out of a W-body with 3.33 gears in it? Would I need to make any changes other than the transmission?

[3400-95-Modified]

Depending on what year it comes from you may need to swap over the rage selector switch to be the one from your 95, also you might want to open the diff side of the trans and swap the tone ring on the diff for the one that comes out of your car, W-bodies are a 30 tooth vs 29... not a huge deal but your speedo will be 5% off so your limiter will come into play about 104 instead of 109 or 109 instead of 115 depending on which one you have. I know you can use up to a 1999 4t60e and swap it into an older car with NO problems. Only differences may be the side cover structure which is easy to swap over, and also the range switch may have one more position, the 1 gear location... My car is a OD, D, L setup and some are D, 3, 2, 1 No biggie because your floor shifter will stop the cables from going into a gear your ECM wont recognize.

I actually went the other way with mine, I just pulled my whole trans apart and changed the drive and driven gears, because if you notice both the 4WSW and a W-body have a 3.33 diff, so I just swapped from 37/33 chain gears to 35/35. I started with a 94 trans, if I did that to the 95 originally in my car I would have ended up with a 3.29 final.