Picked up a 06 5.3L 4x4 tahoe awhile back to haul the kids around. It has the soggy 3.42 gears and a 32" tall tire, all stock. I mostly drive in town and short highway trips 70 mph and under. When I take a long trip it's thru the rocky mountains and thing is always in and out of od on even the slighest hill. Thinking about stepping it up to a 4.10 gear. Just wondering if anyone has made the switch and how much it helped. Mpg is not real good right now hate to make it too much worse.

 

It will help a good bit.

Gas mileage is dependent on your right foot.

If you have someone do it, you're looking at close to $1k (maybe more) to change out the front and rear sets. Yes, you have to change them both out.

 

Thanks, and yes I would do both and do them myself. I have a buddy with a 4x4 shop that has factory 3.73 and 4.10 take outs. I figured the 3.73 wouldn't be enough difference for the swap. I do run it pretty hard. Speed limit on I15 and I 70 is 80 mph a lot of the way so Im running it 85 mph in straight drive thru there. Figured with 4.10's it would pull od. The rest of the time It gets driven pretty easy.

 

I am on 4.10s with ~34in tire (285/75/16) and I like it. I am however going to 4.56 soon, for more grunt and getting the pig off the line better.

I think you will be happy with the 4.10 swap.

 

I think you would be happy with the 4.10s all around. Be around 2400rpm at 80mph

(Arthursc2) just so you know a 285/75/16 is a 32.8 not a 34

 

Thanks. I said "about 34in"

I knew I wasnt a 33, but I thought I was on the plus side of it, not the minus.

 

Right now Im in Colorado with it at 6500' elv and it's so guttless it's dangerous lol. Almost got T boned last night because it would not go. My Dmax pulling 12k worth of trailer had way more power up here lol.

 

I'm actually about to make that exact swap. My 3.42's felt decent with the 4l60e and 29" tire, but after the 4l80e swap it's horrible. I think 4.10's are going to wake it back up and I think they would for you too with your weight and tire height.

 

You may want to go 4.56 with the 80 having a higher (numerically lower) first gear.... 4.10s are good for 4l60 on highway.... Granted i am at sea level and nowhere near elevation of rockys but with 35s i stay less than 2000rpm at 70mph.... Mileage was better in my truck with the 3.73s but by maybe 2-3mpg on highway....