2011 3.42 gears VS 2008 3.73 gears --bigger tires

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Mighty Hd

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First, I must say the 3.42 gears in my 2011 tahoe suck. The thing feels like a slug and as if I were towing a 5,000lb trailer pulling away from a stop sign and driving around through the city. On the highway it certainly shines with 20mpg cruising along at 75mph, but go to pass someone and you better back off, floor it and allow plenty of time to gain speed.

Bottom line...in comparison to my 08 that had 3.73 gearing, it absolutely blows.

The question now:
For those who have put bigger tires on 2011+ models with 3.42's, how badly did it decrease the acceleration and fuel mileage?

How much can I expect to pay to swap in 3.73 or 4.10's for the front and rear?

Thanks!
:Handshake:
 

akbrener

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The tires are probably gonna kill the off the line, but will help fuel mileage on the other end (highway). You will only see it if you calibrate your speedo though as the tire will be spinning at a different rate and you odometer will be off as well. Adding tires is essentially turning that 3.42 into a 3.23 or 3.08 gear.

As for the cost to swap, you are probably gonna pay around $500 for parts and labor per axle, depending on the shop of course.
 

JustJake

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My 08 came with 4:10s and I love it! I still get 18-20 hwy and off the line the thing has lots of power
 

Brock

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I have 3.42 & 35" tires. Definitely a huge loss in low end power. Re-calibrated speedo (a must), but can't really tell about MPG change. My truck has a 6-speed tranny, and it is VERY annoying at highway speeds - switching back and fourth from 5th & 6th.

Was quoted $1650 by 4 Wheel Parts for gear change both axles. Yikes!! Have not done it yet, but it's on the list.

Yes, those tires probably turned my 3.42 into a 3.08, but I'll bet it will go 160+ MPH!!
 

Zed 71

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Bottom line...in comparison to my 08 that had 3.73 gearing, it absolutely blows.

The question now:
For those who have put bigger tires on 2011+ models with 3.42's, how badly did it decrease the acceleration and fuel mileage?

How much can I expect to pay to swap in 3.73 or 4.10's for the front and rear?

Thanks!
:Handshake:

Did the 08' have the same 6-speed tranny? Just curious.

Cost is about $800 per axel.

My 08 came with 4:10s and I love it! I still get 18-20 hwy and off the line the thing has lots of power
 

08z71tahoe

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how do you find out what gear ratio ur truck came with?

just looked on my sticker... i have a 3.42 rear ratio...

---------- Post added at 10:59 AM ---------- Previous post was at 10:49 AM ----------

http://www.4lo.com/calc/geartire.php

just found this site... i haven't thought about changing the gears cause it performs fine... but if i did, what would you change it to?
 
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imi4tth3w

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there are quite a few things to take into account when deciding gears..

in order for me to give you a correct recommendation, need to know:
engine (5.3, 4.8, 6.2 etc...)
trans (4l60, 4l80, 6l80, etc)
current wheel/tires
driving style/what you want to get out of your new gears (obviously more power. but how much more power? do lots of highway driving? city driving? worried about mpg?)


some examples.

you can see my setup in my sig. with 3.73s i can get about 16mpg on the highway. i'm also bb 93 oct tune which helps quite a bit. but she's a bit of a dog from the start. one of these days i'll upgrade gears, but for now she stays.
 
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