2018 silverado 1500 2wd g80 swap

[Facehead]

6 minutes ago, Mike GMC said:

Do you have a 1500 or 2500?  What engine?  Max tow package?

1500, 2wd, 5.3l v8, no towing package, GU6 3.42 rear end

[Mike GMC]

A good shop should be able to get you the right parts.  I guess it's possible that the 2wd got the 9.5" axle instead of the 8.6".  Without looking at it it's tough to tell.

[Facehead]

8 minutes ago, Mike GMC said:

A good shop should be able to get you the right parts.  I guess it's possible that the 2wd got the 9.5" axle instead of the 8.6".  Without looking at it it's tough to tell.

My truck has the 9.5" 12 bolt axel/ rear end. Any idea if changing my rear differential would void my warranty?

[Facehead]

16 minutes ago, Mike GMC said:

A good shop should be able to get you the right parts.  I guess it's possible that the 2wd got the 9.5" axle instead of the 8.6".  Without looking at it it's tough to tell.

I found this one that I believe will fit my truck.

https://eastcoastgearsupply.com/i-23993370-gm-9-5-semi-float-detroit-true-trac.html

[Mike GMC]

It certainly wouldn't void all of your warranty, but it could void the warranty on the rear axle.  Talk to your dealer before you have any work done.  They may be willing to keep the entire warranty in tack if they do the work.

[Mike GMC]

That may work, but I would let the shop aquire the parts.  If you buy them and they don't fit it's on you.  If they order them, they will take care of getting the right ones if something goes wrong.

[muddkatt]

Someone posted a while back saying the RPO codes on the 2018's were not on the sticker in the glove box any more. Easy way to check for G80 is to do a low speed burn out in dirt. 5-10 MPH is all it takes to see if the drivers side wheel spins . 2 marks = G80, 1 mark = open rear end.

[Facehead]

6 minutes ago, muddkatt said:

Someone posted a while back saying the RPO codes on the 2018's were not on the sticker in the glove box any more. Easy way to check for G80 is to do a low speed burn out in dirt. 5-10 MPH is all it takes to see if the drivers side wheel spins . 2 marks = G80, 1 mark = open rear end.

I found the RPO codes and the only one pertaining to the rear axel is GU6 so I am sure I do not having the g80 locker. I will have to get wiht my dealership about ordering and installing one for me.

[Mike GMC]

GU6 is just the gear ratio, 3.42.  Mine also has a 12 bolt cover, but I believe we both have the 8.6" rear axle.  The 9.5" is the 14 bolt used in the 3/4 ton and the max tow 1/2 ton trucks.  It is much bigger and stronger.  I had never counted the cover bolts before, but the oval shape cover looks the same even though it has a couple extra bolts as the old 10 bolt axle.  The 14 bolt cover is not oval, it's more of a double trapazoid with straight sections.

[Nanotech Environmental]

I converted the G80 in my last truck to a Truetrac, as the G80 stopped working properly. If you're starting from scratch, I'd definitely go with a Truetrac if you can. They can usually be bought for around $550-600 or so, plus bearings, other installation parts and labour.

It shouldn't void your warranty, but it's best to find out from an expert on that to be sure.

I have the G80 in my 2017, although they are supposed to be improved from the older versions, it still makes a big bang when it engages sometimes. 

The problem with the G80 is that it's designed to ultimately fail in service. The basic design ensures that significant shock loads will be forced on the components & they eventually break.

[Facehead]

12 hours ago, Mike GMC said:

GU6 is just the gear ratio, 3.42.  Mine also has a 12 bolt cover, but I believe we both have the 8.6" rear axle.  The 9.5" is the 14 bolt used in the 3/4 ton and the max tow 1/2 ton trucks.  It is much bigger and stronger.  I had never counted the cover bolts before, but the oval shape cover looks the same even though it has a couple extra bolts as the old 10 bolt axle.  The 14 bolt cover is not oval, it's more of a double trapazoid with straight sections.

I just wish I could find a list of compatible differentials or someone who has the same rear end as me that has installed a truetrack because from what im researching and on eatons website in the vehcile application guide I need 3.73 gear ratio or higher to put the truetrac in.

[Mike GMC]

From the research I've done, this is still the same old 8.6" 10 bolt on the inside.  30 spline axles and all.  Bearings seem to depend more on the carrier as some will require a larger inner diameter than others.  Unless you are installing this yourself, let your shop figure this out.  They will disassemble, measure and order the right parts.  Even if that shop is the dealer.  You'd likely have to do the same thing if you were doing the work at home.

[Facehead]

1 hour ago, Mike GMC said:

From the research I've done, this is still the same old 8.6" 10 bolt on the inside.  30 spline axles and all.  Bearings seem to depend more on the carrier as some will require a larger inner diameter than others.  Unless you are installing this yourself, let your shop figure this out.  They will disassemble, measure and order the right parts.  Even if that shop is the dealer.  You'd likely have to do the same thing if you were doing the work at home.

I called my saleman... she informed me that if I would bring the truck into the service dept and have them purchase and install the g80 into my truck it would cost over $5000,  $3700 for the differential and $1900 for labor. Also on top of all that if i get them to install the g80 my warranty will go down to 12 month/ 12000 mile warranty.... These people are out of their mind... I can buy an entire axle with a g80 in it from a 17-18 for less than $1500 brand new. A detroit truetrac differential is $450-$600 and a new ring and pinnion to fit in my chuck and fit that diff is less than $200 and labor is like $400-$500 depending on the shop. I have no idea what to do now lol.

[Mike GMC]

Try another dealer.  That is ridiculous.  They obviously don't want the job.

[Facehead]

16 minutes ago, Mike GMC said:

Try another dealer.  That is ridiculous.  They obviously don't want the job.

That is what I was thinking , but then again maybe the lady thought I meant swapping the entire rear end/ axle and not just the differential.