Gear swap

[StevenW30]

Howdy y'all, happy Saturday!
Planning on doing an upgrade to 3.73 in my 2012 ppv 4x4. Question for the wise masses... first, obviously any heads up on what anyone has purchased or recommend on who to go through. Secondly, I believe there is a 300 mile break in period (recommended) before towing or stomping on it. Do I just wait wait to get it tuned? That makes the most sense to me, but I want to make sure.
I can't do the work, local garage I trust will handle it.
As always, thanks for your help!
Steve

 

[Marky Dissod]

Planning on doing an upgrade to 3.73 in my 2012 ppv 4x4.

Do you mean SSV, since it is a 4x4?

I believe there is a 300 mile break in period (recommended) before towing or stomping on it.
Do I just wait wait to get it tuned? That makes the most sense to me, but I want to make sure.

Actually you may want to ask your tuner about a shift schedule adjusted specifically for the purpose of breaking in the new axle gears,
followed by the post-break in shift schedule.
Either way, no, do not wait to get tuned; the most common mistake GM vehicle owners make is deciding against / delaying getting tuned.

 

[StevenW30]

Do you mean SSV, since it is a 4x4?
Actually you may want to ask your tuner about a shift schedule adjusted specifically for the purpose of breaking in the new axle gears,
followed by the post-break in shift schedule.
Either way, no, do not wait to get tuned; the most common mistake GM vehicle owners make is deciding against / delaying getting tuned.

Here's the thing, I have the build sheet and eventhough it's 4wd with tow package, it's a ppv trim. I know they're typically not, but this one is apparently a special build for Texas Dept Homeland Security... even Hendrick Chevy here looked up the VIN to confirm it when I first bought it.
Ok, so as long as I let my tuner know they're new gears, he'll be able to tune without and damage... appreciate the feedback!!!

 

[Marky Dissod]

So your RPO SPID label has 'PPV', but NOT '5W4'?

Pretty sure you already know, break in axle gears as follows:
*no driving at any constant speed - some people forget this; either accelerating or decelerating, no cruising
*taking it easy / pretend your whiny lil pain in d'arse rider is proud to have motion sickness
*1st 3 break-in drives, 15-20 min, then cool down for at least 20min (up to 30min if it's really hot out & you parked on hot blacktop)

If you know of hypermiling, two basic techniques are very useful for axle gear break-in:
*drive so as to plan in advance to use your brakes as little / as gently as possible
*avoid cruising @ (let's say 60MpH) by GENTLY accelerating to 65MpH then coasting down to 55MpH then repeating
in practice GENTLY accelerating to 63MpH then coasting down to 57MpH works as well

If you get better MpG with 3.73 than you got with the lame@$$ axle gears GM originally provided (3.??),
that proof will motivate many more people to upgrade their axle gears,
which will help more of these powertrains last even longer.

After 500 miles, drain out the old axle fluid, add new axle fluid, have fun ...
(I recommend a 2nd 'break-in' drain & refill @ 3000-5000 miles if vehicle works or plays HARD, then stick with severe service schedule if not more often)

As said before, if your tuner takes a shine to you, they might even provide an axle gears break-in tune,
to temporarily discourage enthusiastic driving / encourage more conservative driving

 

[StevenW30]

So your RPO SPID label has 'PPV', but NOT '5W4'?

Pretty sure you already know, break in axle gears as follows:
*no driving at any constant speed - some people forget this; either accelerating or decelerating, no cruising
*taking it easy / pretend your whiny lil pain in d'arse rider is proud to have motion sickness
*1st 3 break-in drives, 15-20 min, then cool down for at least 20min (up to 30min if it's really hot out & you parked on hot blacktop)

If you know of hypermiling, two basic techniques are very useful for axle gear break-in:
*drive so as to plan in advance to use your brakes as little / as gently as possible
*avoid cruising @ (let's say 60MpH) by GENTLY accelerating to 65MpH then coasting down to 55MpH then repeating
in practice GENTLY accelerating to 63MpH then coasting down to 57MpH works as well

If you get better MpG with 3.73 than you got with the lame@$$ axle gears GM originally provided (3.??),
that proof will motivate many more people to upgrade their axle gears,
which will help more of these powertrains last even longer.

After 500 miles, drain out the old axle fluid, add new axle fluid, have fun ...
(I recommend a 2nd 'break-in' drain & refill @ 3000-5000 miles if vehicle works or plays HARD, then stick with severe service schedule if not more often)

As said before, if your tuner takes a shine to you, they might even provide an axle gears break-in tune,
to temporarily discourage enthusiastic driving / encourage more conservative driving

Yup, PPV.... like I said, Hendrick Chevy looked up the VIN to make sure I had the correct build sheets. We all kinda scratched our heads on that one.
I read up on hypermilling when doing my research, but I can't tell you how helpful you're being walking me step by step. I won't be harsh on her at all, even after the initial break in, but will be towing the Rockwood for camping at some point thereafter. My tune guy is another firefighter from the next town over, so I'm good there and sure he'll do me a solid. He did the AFM/DOD/VVT delete with all the new bells and whistles that went with it....

 

[StevenW30]

Yup, PPV.... like I said, Hendrick Chevy looked up the VIN to make sure I had the correct build sheets. We all kinda scratched our heads on that one.
I read up on hypermilling when doing my research, but I can't tell you how helpful you're being walking me step by step. I won't be harsh on her at all, even after the initial break in, but will be towing the Rockwood for camping at some point thereafter. My tune guy is another firefighter from the next town over, so I'm good there and sure he'll do me a solid. He did the AFM/DOD/VVT delete with all the new bells and whistles that went with it....

Oh, it's originally a 3.43