Gearing question on my 2012 PPV

[Matus Mrocek]

Hi guys,
first post so here is a little intro - my first child was born a couple months ago and we needed a Baby Transport Vehicle. I chose the 2012 PPV for the "active" safety aspect of driving one. (people slow down, pay attention and drive at their best, for the most part) As well as the space, structural reinforcements, upgraded cooling (I live in Phoenix,) etc.

My question is the following: Just like all of you, I assume, I have the 5.3 LMG with 6 speed 4L80 and 3.07 rear diff. I will never take the tahoe above 100 max and would like to tow with it (my rubicon and hellcat.) So I want to re-gear... I know stock tahoes are 3.73 but they also have taller tires. (Eventually I will increase the tire size a little) I am thinking of getting 4.10 gears - for quick take off and good towing, but need to figure out how high the RPM's will be on the freeway doing 80-85mph. Does the tahoe have a double OD? Final gearing ratio? anyone have some first hand knowledge on gearing to 4.10 and stock ppv tire size? Is there a good calculator for this somewhere that I missed in my search?

I appreciate any help and ideas. Thanks!

 

[Doubeleive]

structural reinforcements? did someone put a roll cage in it?

 

[Matus Mrocek]

structural reinforcements? did someone put a roll cage in it?

Extra crossmember? I read somewhere that it has added frame reinforcements.

 

[Doubeleive]

hmm never heard of that, I would to see pictures of said extra crossmember because if they put them on the ppv/ssv I can put it on mine, i'm always looking out for little things like that.

 

[mikeyss]

This site helps a lot:
https://spicerparts.com/calculators/transmission-ratio-rpm-calculator

Your transmission is a 6L80, and it has 2 overdrive's. 6th gear is a .667, you'll need that number when using the site I added. Your PPV may have 3:42 rear gears, GU6 is the code for that I believe.

 

[Ilikemtb999]

My ssv has 3.42 gears. I think it’s a good compromise between gas mileage and get up and go. I’ve had gmt900’s with 3.73 and up and the mpg really tanks.

 

[Matus Mrocek]

This site helps a lot:
https://spicerparts.com/calculators/transmission-ratio-rpm-calculator

Your transmission is a 6L80, and it has 2 overdrive's. 6th gear is a .667, you'll need that number when using the site I added. Your PPV may have 3:42 rear gears, GU6 is the code for that I believe.

Thanks for the calc. I def have 3.08’s. Thinking 3.73 might be the way to go.

 

[Matus Mrocek]

Thank guys, looks like I found my answer. I'll go with the 4.10 gears, as at this point doing 85mph I would be running at only 2700rpm. Once I'll up the tires to 30/31, it will drop down to 2600/2500. This should make the truck a lot more driveable as most of the time I run these speeds is me going from Phoenix (1000ft) to Flagstaff (7000ft) and currently it's constantly downshifting go get more power just to maintain the speed uphill. I know the mpg's will suffer but I didn't buy the Tahoe for its great mpg's. (Actually deactivated the AFM as soon as I got it.)

@mikeyss Thanks for the link and the .667 as that was my missing link.