I have an A6 with 2.72 rear gears I beleive and would like to go to a 3.42 rear gear. But my question is why go with 3.42 gears instead of 4.10 gears. Whats the biggest difference?

Thanks

Jerry

 

A6 has a 4.02 first gear, go with 3.15. The 3.42 will spin it pretty high out of the power band and the 4.10 would be insane.

 

I had a '70 bb vette with at and 4:11 gears. The car was a beast on the street. The only draw back was fuel mileage, which dropped 30% when I went from 3:08's to the 4:11's, and that was when premimum fuel was $.75 / gal.

 

Thanks guys, I guess Ill stick with the 3.42 or go with the 3.15, have to do some research there.

 

Yes do, just droping a set of gears is not the answer, and don't forget to buy your personal gas station, your milage will drop like a rock.

 

want to talk to CHuck COw. Hes pretty good on that gear stuff and tuning it after

 

I have 3:42's and still get over 31 mpg highway. I do have the m6 though.

 

Mileage doesn't drop as much as you might think. I just got back from New York, where I had a set of 3.42's installed. On the way there, (800 miles), I averaged 29.3 mpg running at 70-75 mph. On the return trip with the 3.42's running a different route for about 250 miles, I averaged 26 mph running the same speed. So on the interstate, I lost about 3 mpg, or about 10%. And probably even less than that if I had run the same route, or if I had not played with the throttle as much.

Tell you what, run your A6 on the interstate in 5th gear, and that's what the 3.42 will equate to. 70 mph cruise with the 2.56's was about 1600 rpms, and with the 3.42's it's now a tad less than 2000. About 1975 according to the data logs.

And you won't believe how much the gears wake the car up. Much more pickup and acceleration through out all the gears. And you can break the tires loose at 60 mph on a full throttle downshift. You had better have a firm grip on the steering wheel when you try that.

Long trip, but well worth it in my opinion. This is how GM should have built this car originally. It all depends upon how you use the car. If it's your daily driver and you need the last tenth of gas mileage, then by all means stay stock. If you drive your car for sport, then go for the gears. And by the way, you don't have to jump to the 3.42's. You can always pick the 3.15's

 

I think I'd wait awhile to see how this gas thing plays out.They were talking about $4/gallon this morning on one of the news talk shows and that's for regular.

 

My question not to take the subject away from the OPs is where can I buy the 3.42 gears? Being in Hawaii does have it's drawbacks like not being able to work with Chuck COW.

 

You can send Chuck your computer and he can do a "mail order tune". Not exactly the same as being there, but better than anything you can find locally. I guess living in Paradise does have it's drawbacks!

 

I don't think a mail-order will address the 3.42 change, as there are adjustments to the shift points to accommodate the new gear. Those changes take place in the TCM which cannot be done remotely.

But if you have HPTuners, then someone could send you the tune and you can install it yourself and will get the full benefit.

Just something to think about.

 

If you search there are several real good calculators which gives you the facts about how much each gear changes things.

Gears are the best mod available - engine,tranny, and most drive train remain under warranty - but the fun meter jumps off the scale.

3.42's are about 10% more than 3.15's So if you lose 3 mpg at most - it all depends on how much your drive the car. I average 500 miles per month so if I used to get 25 and now I get 22 - even at $4 a gallon - my cost of great fun per month is 500/25 = 20 500/22 - 22.7 - 20 =

2.7 * $4 = $10.80 Yes that is Ten Dollars and 80 cents.

Hope that puts a different perspective on the greatness of the gears.