anybody running an auto with 3.73 or 4.10 gears?

[Jhunter]

I am looking to do the gear change but it's my daily driver and don't want to kill my gas mileage. What are you running and whats your approx mpg?

I am leaning to the 3.73 right now.

Thanks for any help and if you live in sc/nc and are close and would not mind giving me a ride to get a feel of the gear that would be great too.

 

[Deleted member 38176]

I've got 4.10's and my mileage stayed almost the same as with stock gears. I do very little highway driving. Its the highway that will hurt MPG's w/ gears.

 

[007]

3.73s would be a HUGE mistake. I've run 4.10s for the last 9 years. Wouldn't want anything less.

SCT Xcal/SF3 is amazing when paired with the gears.

 

[Jhunter]

I don't want to be too sharp off the starts, like I said daily driver 50 mile round trip to work. I like to stay over 20 mpg. Right now I get a little over 22.

 

[Deleted member 38176]

I believe Sonic04GT said that he gets about 23mpg's with his gears and a 5-spd. An auto might be 1-2mpg's lower. You should get around 20mpg or so with the gears.

 

[Maxpowers]

I've gotten as good as 23 mpg with gears on the highway.

Use the search function. There are tons of threads about gears.

 

[sneaky98gt]

No first hand experience with those gears, but my granddad's auto 04 Mach 1, with 3.55 rear gears, gets around 24-25 on the highway. So I can't imagine 3.73s being too much less than that.

Also be sure to think about the future plans for the car, as in, how fast you are going to make it. 4.10s will only allow for about 110 mph in the 1/4 with 26 inch tall tires, whereas 3.73s will get you about 122.

I'm planning on trapping upper teens here in a month or two, and I'm also wanting to change out the gears. 4.10s would be WAY too much for my car, whereas 3.73s would be just right.

Just something else to consider.

 

[san~man]

I don't want to be too sharp off the starts, like I said daily driver 50 mile round trip to work. I like to stay over 20 mpg. Right now I get a little over 22.

When I had mine, I drove minimum 90 miles a day, often much more. Don't be a princess and have regrets later.

Besides, you didn't buy this car because it gets good mileage in the first place.

 

[KBExperience]

I had 3:73's in mine, and I got over 20. The best I ever got was 26 on a all highway tank.

 

[jmc01gt]

I've had 3.73's in mine since 2005 and the highway mileage did not suffer at all. I used the car for commuting 50 miles each way for a while and if I wasn't beating on it I was getting 23.5-24mpg with some city driving in there too. On the highway I would cruise between 75-80 mph.

On long trips that were all highway I could get over 25mpg, and that would include some chasing traffic over 100mph for decent stints as well...the Florida Turnpike from Orlando to WPB gets some fast drivers on it.

I love my 3.73's, but now that I put an Eaton on the car I find that they are too deep with the T-45's 3.37 1st gear. I think I'll keep the gears and swap in a 2.66 1st gear T-56.

 

[3ponyshow]

If I really behave and stay out of boost, I get 20 even with my 3.73's, but that's at +/- 80 mph.

 

[Jhunter]

Thanks for ther help men.