Gears & Axles - 3.42 to 3.73

Wondering if anyone has switched from 3.42s to 73s. Wondering if it is even worth the time and money. 4.10 just seems to low to me for a street car.

I did that exact gear swap .I would do it again ,money well spent.If you got the a4 373 is where you wana be .410 is better fitted with the m6.Cost me about 275 in parts and 250 labor to get installed.

I do have a M6, 4.10 just seems so low to me.

Im running 4.11s in my A4 and its perfect around town, cruise @2000 rpm is around 50mph.

Anything less than 4.10's with an M6 would be a waste IMO and you would hardly notice any change. The only way I would go with less than a 4.10 gear is if you are making a lot of power or running N2O. The 4.10's are VERY streetable. Also, if you want to do a cam swap in the future you will be very happy you went with more aggressive gearing.

I wouldn't bother swapping from a 3.42 to a 3.73. I went from a 2.73 to a 3.42 and WOW, but from a 2.73 to a 3.23 you couldn't even really tell.

there is a definite difference going from 3.42 to 3.90. about 2 car lengths in a street race which is about .2-3 at the track.

I'm torn between a 3.90's or 4.10's myself. I do A LOT of interstate driving.....

Going from 3.73's to 4.10's was one of the best mods I did. I wasn't expecting to feel much, but it was huge. I can only imagine what going from 3.42's to 4.10's is like.

well my car was stock except intake, and i went from 342s to 373s m6 car....i noticed a good difference and prefer it over 410s

or 342s to 430s oh yeah cant wait for mine!!just run a bigger tire.

I had 4.10's in my camaro and loved it, really fun to drive. I was getting 240 miles to a full tank mostly stop and go traffic. I have to agree with above if you go with a cam in the future probably a good idea to go to 4.10's. Wanted to state something although you can break your rear end even with the stock 3.42's you increase that chance of breaking it for sure going to 4.10's. I fortunantly never had a problem with it either way you will be happy with a gear swap.

I definitely agree with going ahead and making the jump to 4.10s. Its going to make a huge difference on how the car performs.

I had 4.10's in my camaro and loved it, really fun to drive. I was getting 240 miles to a full tank mostly stop and go traffic. I have to agree with above if you go with a cam in the future probably a good idea to go to 4.10's. Wanted to state something although you can break your rear end even with the stock 3.42's you increase that chance of breaking it for sure going to 4.10's. I fortunantly never had a problem with it either way you will be happy with a gear swap.


Why would there be an increased risk of breaking? You're giving the rear a mechanical advantage. Only thing I could think of it the smaller teeth?

I wouldn't bother swapping from a 3.42 to a 3.73. I went from a 2.73 to a 3.42 and WOW, but from a 2.73 to a 3.23 you couldn't even really tell.

I disagree...2.73 to 3.23 is a good difference

I went from 3.42 to 3.73 in my m6 car and noticed a descent difference, the car just felt lighter upon accelerating and going up overpasses just felt easier. Couldn't tell you if it improved at all on the track with any certainty.

I'm now going from 3.73s to 4.10s because I took the n2o off my car. I'm sure that is a big difference.

Really what needs to be calculated is estimated trap speed in the 1/4 and what gear ratio achieves that # and your redline. There is no rule of thumb when it comes to gearing IMO.

dr whigham, i do alot of highway also and did 6spd swap and retained the 3.23 from the auto. it started whining and went to S60 the other day. and was torn between 3.54 and 3.73 and looked at the difference where i run at around 80mph and decided with the 3.54 for down shift purposes from 6th to 5th to 4th @ 80mph it was like a 400rpm difference between the 3.23 and the 3.54 and even higher with the 3.73. i based my decision on the way i drive the highway i didn't want to high of gears for down shift passes.for example shifting into first and letting clutch out to soon at a stop. the oldman....

I have a M6. I'm getting ready to swap gears. But is ther a big difference between 3.90 and 4.10? I plan on H/C/I down the road. Nothing to Radical tho. I would appreciate any input from anyone with past knowledge on the 2...