Who can I go to to change gears

[race24x]

I have a 2014 2SS M6 I want to swap my gears for 3.91s. Who can do this for me and what should it cost? I am not sure I trust any shops around Maine to do this. I assume I would have to take the rear diff out anyway.

[zlathim]

Any reputable drivetrain shop should be able to handle it. Call a few and ask them if they have any experience with the 8.6" IRS GM diffs. You can likely save some money by removing the differential and taking it to them, but you shouldn't have to if you don't want to.

That being said, I thought I wanted 3.91 gears in my M6. After talking to acammer, he convinced me that 4.10s are the way to go on the M6. Man, I'm glad that I listened to him. I love the 4.10s and I'm pretty sure I wouldn't have been nearly as pleased with the 3.91s.

IMHO, if you can source a good complete diff with 3.91s and are doing gears on a budget, go for it. If you are installing a new set of gears into your diff, then go with the 4.10s.

Here is the conversation if you are interested in reading through the things acammer wrote: https://www.camaro5.com/forums/showthread.php?t=542787

[hammdo]

GPI can do it if you want to ship it. They did mine that way...

-Don

[race24x]

Originally Posted by zlathim

Any reputable drivetrain shop should be able to handle it. Call a few and ask them if they have any experience with the 8.6" IRS GM diffs. You can likely save some money by removing the differential and taking it to them, but you shouldn't have to if you don't want to.

That being said, I thought I wanted 3.91 gears in my M6. After talking to acammer, he convinced me that 4.10s are the way to go on the M6. Man, I'm glad that I listened to him. I love the 4.10s and I'm pretty sure I wouldn't have been nearly as pleased with the 3.91s.

IMHO, if you can source a good complete diff with 3.91s and are doing gears on a budget, go for it. If you are installing a new set of gears into your diff, then go with the 4.10s.

Here is the conversation if you are interested in reading through the things acammer wrote: https://www.camaro5.com/forums/showthread.php?t=542787

Why the 4.10s? This is a street car daily summer driver with a Kraftwerks SC and 650 HP I dont drag race it often actually havent once yet. I might once or twice in its life.

[race24x]

Originally Posted by hammdo

GPI can do it if you want to ship it. They did mine that way...

-Don

Who or what is GPI

[zlathim]

Originally Posted by race24x

Why the 4.10s? This is a street car daily summer driver with a Kraftwerks SC and 650 HP I dont drag race it often actually havent once yet. I might once or twice in its life.

OOps, didn't realize you were boosted. A lower ratio is probably right for your application.

[StingrayblueSS]

I've got two quotes for 1100 to 1200 just for labor. Seems high to me.

[hammdo]

Originally Posted by race24x

Who or what is GPI

https://gwatneyperformance.com/

https://www.camaro5.com/forums/ad_thesponsors.php

PM Rhino79 or GPI Aaron.

They do a ton with forum members...

They’re also a Chevy dealer too!

3.91s may be a bit much for FI. I had them and went down to 3.45s

-Don

[zlathim]

Originally Posted by StingrayblueSS

I've got two quotes for 1100 to 1200 just for labor. Seems high to me.

I paid about $600 for labor, so it does seem kinda high. That being said, my dyno tune cost way more than most people here are paying so who knows...

[ZZZTOPZZZ]

Originally Posted by zlathim

Any reputable drivetrain shop should be able to handle it. Call a few and ask them if they have any experience with the 8.6" IRS GM diffs. You can likely save some money by removing the differential and taking it to them, but you shouldn't have to if you don't want to.

That being said, I thought I wanted 3.91 gears in my M6. After talking to acammer, he convinced me that 4.10s are the way to go on the M6. Man, I'm glad that I listened to him. I love the 4.10s and I'm pretty sure I wouldn't have been nearly as pleased with the 3.91s.

IMHO, if you can source a good complete diff with 3.91s and are doing gears on a budget, go for it. If you are installing a new set of gears into your diff, then go with the 4.10s.

Here is the conversation if you are interested in reading through the things acammer wrote: https://www.camaro5.com/forums/showthread.php?t=542787

I'm thinking about fiddling with the rear end, but it's not a priority right now with the cam and heads in the works. Question: What device/tool/procedure did you use to change-up the speedometer?

[hammdo]

Hp tuners , EFI Live, or other tuners lets you set the ratio...

-Don

[gsxrturbo]

I have 3.91's with m6 and 845rwhp,cant hardly shift fast enough,but 4.10 would be great on lower hp levels