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Posted

I've decided on a 2020 AT4 put down a deposit a couple days ago. Truck is in transit. I decided I would only buy one that had the SU5 (GM) front axle not the SU4 (AAM) front axle. I found a couple trucks that were optioned the way I wanted but every time I had the dealer pull the build sheet they were built in Mexico with the AAM axle. Now I got nothing against Mexico my problem is with the AAM axle. I found a carbon black metallic AT4 that started with 1 in the vin so I know that's built in the US. had the dealer pull the build sheet and sure enough it had the SU5 axle (GM). So I bought it. As I looked around at other carbon black AT4's at various dealers all the carbon black ones I looked at were built in the US. So.... my question is does anyone know if carbon black metallic AT4'are only built in the US. 

Posted

No clue but please tell me the difference between these front axles. 

  • Like 1
Posted
4 minutes ago, smrr1 said:

No clue but please tell me the difference between these front axles. 

Yeah now I'm curious also.

Posted

There's a thread here (may be under troubleshooting) on the really annoying jingle some (all?) the AAM axles make in 2wd. Just search for jingle.

Posted

My 19 which was built in Fort Wayne had the SU4 axle and did not make any strange noises. Had other problems with it but not that one.

Posted

No clue what axle mine has but almost 1 year and 11k miles. I hear no jingle. 
 

2019 6.2/10 AT4

Posted

T1 GMC and Chevy 4x4 trucks use one of 2 front axles, AAM and GM sourced. SOME owners of the AAM axles are having issues with the front axle making noise. My main concern is that GM seems to be struggling with coming up with a fix and I don't want to drop 50+ large on a truck and hope I don't get a noisey axle, that there's no current fix for. Thats why I searched for a truck with the GM axle. I think GM will get it figured out at some point I mean its an axle. 

  • Like 1
Posted

That's what I did went for one with the SU5 axle and post 3/19 build with the Mobil1 HP factory fill tranny.

 

All the US builds I checked when purchasing had SU5 axles must have something with local sourcing of parts and thus SU4 supplier used for Mexican builds. Same probably goes for dealer sourcing mine had only 1 Mexican build for 32+ US builds in the lot.

Posted

With the previous Shakerado's, axles sourced from Mexico were identified as possibly being responsible for the Chevy Shake.  Who knows how true it is but I agree, machined, high RPM parts seem to have better quality when they come from the US.

  • Haha 1
Posted
20 hours ago, RetChief said:

my question is does anyone know if carbon black metallic AT4'are only built in the US. 

It appears Carbon Black Metallic is a Fort Wayne only color, no matter the trim. All 45 trucks near my zip code are 1 VIN. 

  • Thanks 1
Posted
20 hours ago, RetChief said:

I've decided on a 2020 AT4 put down a deposit a couple days ago. Truck is in transit. I decided I would only buy one that had the SU5 (GM) front axle not the SU4 (AAM) front axle. I found a couple trucks that were optioned the way I wanted but every time I had the dealer pull the build sheet they were built in Mexico with the AAM axle. Now I got nothing against Mexico my problem is with the AAM axle. I found a carbon black metallic AT4 that started with 1 in the vin so I know that's built in the US. had the dealer pull the build sheet and sure enough it had the SU5 axle (GM). So I bought it. As I looked around at other carbon black AT4's at various dealers all the carbon black ones I looked at were built in the US. So.... my question is does anyone know if carbon black metallic AT4'are only built in the US. 

 

Any color crew cab can be built in US or Mexico.  

Posted
19 hours ago, smrr1 said:

No clue but please tell me the difference between these front axles. 

 

Suppliers.  Some axles (front and rear) on the T1 1/2 ton pickups are made by AAM, some are made by GM.  Both have different fluid requirements as well.  GM started to produce in house axles again due to capacity/quality concerns from the K2 program.  The AAM ones both front and rear look physically different than the GM ones.    

 

Quote

 

Axles — Front and Rear

There are 2 different axle suppliers, AAM and GMCH for both front and rear. Depending on equipment, some trucks could have different axles on the front and rear. The axle source RPO must be referenced for all parts, including axle lubricant, to ensure the correct parts are used. When ordering parts, the vehicle should be searched by the VIN.

 

  • SU4 / SU7 – AAM Front / Rear
  • SU5 / SU8 – GMCH-GR Front / Rear

GMCH GM “MOE” Emblem
Object ID: 5113277Click here for detailed picture of the image.

The GMCH front axle has a Mark of Excellence (MOE) or “GM” emblem on the LH side of the housing just in front of the pinion flange. The GMCH rear axle has a GM MOE emblem on the bottom in the center.

 

Unique Axle Fluids

GMCH is P/N 19368514 United States and P/N 19368515 in Canada.

AAM is P/N 19300457 United States and P/N 19300458 in Canada.

 

 

See my next post for visuals.

  • Like 1
Posted (edited)

Rear Axles.  Only the 9.5" axle is affected by the two different suppliers (2.7T and 5.3 both L82 and L84).  NHT trucks and 3.0 diesel use the 9.76" axle which comes from AAM, and the 4.3 V6 uses the 8.625" axle from AAM as well. 

 

 

GM 9.5" REAR AXLE

9.5INCHGM.thumb.jpg.8b729718718c0ee056676b7f3a3bd882.jpg

 

 

 

 

 

AAM 9.5" REAR AXLE

 

9.5INCHAAM.thumb.jpg.dd208a09e9e9d2deb30fb31ccd0e7bde.jpg

Edited by newdude
  • Like 1
  • Thanks 1
Posted
4 minutes ago, newdude said:

Front axles. 

 

GM FRONT AXLE

 

GMFRTAXLE.thumb.jpg.f8cf90cc8827c094ca24af7f07258e20.jpg

 

 

 

AAM FRONT AXLE

 

 

AAMFRONTAXLE.thumb.jpg.f51dc2f235f505a563ef4bc0c7267665.jpg

Well there you have it. Thanks new dude, Now I just hope my rear window don't leak.

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