I'm thinking of upgrading to 3.42 gears on my 2004 CE A4 but have some questions:

1. Most importantly, would this invalidate my GMPP Warranty? If so, could I get it done by the stealership (not a good idea, I know) to be covered? I've heard horror stories about stealership installs but is there any other way around the warranty coverage issue?

2. Is this the best way to go as it is a DD and I do a lot of freeway driving and don't want to compromise my MPG too much.

3. Would I have to upgrade my torque converter?

4. What sort of price would I be looking at, for buying the unit and having it installed? Basically an out-the-door price.

The only other mods that I have are Diablo Predator (standard performance tune), Borla Stingers, Borla X-Pipe, K&N dual air intake, high flow MAF and most importantly the performance hood seal

I only really want to increase the acceleration from 0 - 60 and am not interested in increasing top speed. Had a close call with an M3 and wasn't too happy about it

Thanks in advance for all your feedback.

 

I can only speak to part of question 2; I have a 99FRC 6spd and went from 342 to 390 (Dynotech). Very little difference in mileage, no drivability issue, and 6th gear / 70MPH only went up about 150-200RPM. Huge kick in the pants with acceleration though, well worth it.

 

3.42's are about the best all around gear choice for an A4. They do everything well. You wont have any issues with warranty because its a GM part number. Or at least I could not imagine any issues. A dealer can do the install but you will need someone to do a tune to calibrate the shift points and a dealer can not do that.

 

I wouldn't think so as you really should be replacing this with a ZO6 3.42 geared rear end carrying a GM part number. If I'm not mistaken Gene Culley has these right now for about $1200 shipped! That's a killer deal for a warrantied rear end.

Yes, it is. Best all around gear choice for your auto. Will greatly increase the "seat-of-the-pants" feel, 0 to 60 acceleration, and drop quarter-mile times all while minimally impacting mileage. Also, if you are coming from 2.73's this will really help eliminate the low speed "hunt" the transmission does in shifting in and out of overdrive as you'll be operating at a higher RPM.

No, but what an upgrade it would be if done together!! Go with something inexpensive like the TC out of the Chevy Astro Van (do a search) and you'll have an inexpensive upgraded stall converter. Tranny cooler is a wise move on a stock automatic and is to be considered almost mandatory on a rear/converter upgrade.

The Astro Van Converter is around $250 I believe but could be wrong on...it might be a little less. The rearend is $1200 shipped so we're at $1500 more or less in the large stuff. Installation price down here in Miami range from $750 to $950 including all fluids.

The tuner is great because it will allow you to program the tranny to compensate for the new gear ratio. Not a big fan of the aftermarket MAF's as they tend to cause more harm then good...especially when custom tuning is concerned. Long tube headers are your next mod...

 

Pewter Dream just sent me this chart and let me post it here. Thanks for this, it's some interesting info:

 

Thanks for all the great info guys, much appreciated!