I went from 3.23's to 4.10s. I do a lot of combined driving, about 30 miles highway to work, and about 35 mostly city on the way home. My mileage went from about 14.7 city to 18.9, and dropped from about 20ish hwy to about 17.

I run a 32" tall tire. For a moment I was wondering if 4.30s would have been better, but after a long trip last week, Im thinking the 4.10s in the RC would have been better and put 3.90s in the CC.

Overall Im happy though. If I was to do it again, Id probably do the same thing. If I didnt do as much highway driving (trips other than commuting) Id probably go 4.30 if I was to do it over

 

he has a 02 ecsb 5.3/Z06 cam/I6 stall/4:56s/275-40/45ish tire it's killing him in fuel mileage. he put the 4:56s bc he HAD a 4.8 but he got a killer deal on a low mileage 5.3 and swapped em in. now he's wanting to go 3:73s vs 4:10s he's not really worried about 1/4 mile time just yet. the only reason why i went 4:10s in the CC is bc its a 58xx lbs truck, and i race it JUST like i drive it. full of gas/tail gate/spare/bumpers and blah blah. i will be throwing the 3:73s in my W/T if i can't get a set of 3:90s/4:10s traded straight up for em.

 

yeah I do about 20 miles hiway for work some trips of 100 miles one way. I am leaning toward the 3.73's.

So I guess with evrything being the same and swapping rearends, will it be more enjoyable than the 3.23's for the money since ill be running a smaller tire?

thanks

 

It will make a huge difference. With a 30" tire 3.73's will be fine, but I'd lean towards a 3.90 if you're against 4.10's. I'm on 31.5" tires with 4.10's on my crewcab and love the ratio.

 

itll be night and day compared to those car gears.

i know someone that has 3:73s for sale, 100shipped 34k miles

 

I've got stock 3.73's on mine with a 31.5" (265-70-17) tire. Overall, I'm happy with them, but if I was to do it over again, I would go at least 3.90-4.10, not that I'm changing mine. I drive about 80 miles a day 50% highway/50% city. usually average about 16.5 combined, but on road trips I can get 18-20 easy.

However if its just the dog off the line issue, I think your money could be better spent in other areas, say a torque converter. Sure the 4.8's are dogs off the line, but all the NNBS truck are stockish. Alot has to do with the tuning and DBW throttle body. The gears will help, but not as much as you might think IMO.

 

I went from 3.42 to 4.10 on a 29" tall tire. I almost went 3.73 cause i do alot of highway driving, But I went from getting 21 to 19 mpg highway on the 4.10's. Im totally satisfied with the 4.10s!

 

Good info here. Thanks.

What will a shop charge to swap these gears out and set them up?

 

around $300-500.

 

ill never pay that amount, ive already learned how to do it, ill start installing my own from
now on.