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Posted

I sure as heck hope the AAJF one is not for the 4cyl, or 6.2 or 6, 10-speed trans.

 

Because...

 

This picture was snapped today under my 2019 5.3 Ecotec3 / 8-speed RST-Z71 lol

 

My truck shows that it was built 01/19 at the Mexico plant.

 

Im still waiting on the build sheet with the RPO codes on it and assume it will have the "SU4" code for the American axle built one.   

 

Hopefully this helps

AAJF.PNG

Posted
21 minutes ago, Z06JPB said:

Good find! 

 

I did not know there was another AAM produced one. My AAHD is from my Z71 LT  5.3L, 8-speed, Crew Cab.

 

It is possible the AAJF is for a 4cyl, or maybe it’s for the 6.2L, or maybe it’s for a 6-speed or 10-speed trans. 

 

If there are two AAM axles it is very likely there are two GM axles. As far as we know, there are only two RPO codes; SU4 for an AAM axle and SU5 for a GM axle. The RPO doesn’t distinguish any other differences.

 

Will be interesting to see what others have and what engine/trans combo they have.

 

edited: just noticed the description said for a Sierra or Denali. Maybe the AAJF is just for the GMC side.

My Chevy RST-Z71 5.3, 8-speed, Crew Cab, 01/19 build date made at the Mexico plant has the AAJF one.

Posted
25 minutes ago, ILSilverado said:

So today I get a call from GM just 12 days before my arbitration date that they have good news they now have the fix in place for my Silverado. GM said they will call the dealer on Tuesday. Has anyone had this so called fix successfully completed yet?

Yeah sounds like my experience yesterday. Fingers crossed this really IS the fix. 

Posted
12 minutes ago, Matty Patty said:

My Chevy RST-Z71 5.3, 8-speed, Crew Cab, 01/19 build date made at the Mexico plant has the AAJF one.

Haha! Okay so looks like the AAJF and AAHD have same applications. Not much difference between an RST Z71 5.3L and an LT Z71 5.3L. RST Z71 has the 2-speed transfer case correct? I know some RST have the 1-speed case but I think those are non-Z71 models.

 

I see yours was made in Mexico. Mine was made in Indiana. Far stretch but at this point maybe the AAJF went to Mexico and the AAHD went to Indiana? That’s about all I can figure would be the difference between the two.

Posted
31 minutes ago, ILSilverado said:

So today I get a call from GM just 12 days before my arbitration date that they have good news they now have the fix in place for my Silverado. GM said they will call the dealer on Tuesday. Has anyone had this so called fix successfully completed yet?

Well this is good news. Hopefully it is true. Though I’m sure you were looking forward to getting a fresh truck without the repair hassle.

Posted
5 minutes ago, Z06JPB said:

Haha! Okay so looks like the AAJF and AAHD have same applications. Not much difference between an RST Z71 5.3L and an LT Z71 5.3L. RST Z71 has the 2-speed transfer case correct? I know some RST have the 1-speed case but I think those are non-Z71 models.

 

I see yours was made in Mexico. Mine was made in Indiana. Far stretch but at this point maybe the AAJF went to Mexico and the AAHD went to Indiana? That’s about all I can figure would be the difference between the two.

 

That's exactly what I was thinking! That the AAHD went to Indiana while the AAJF went South of the border to Mexico.

 

Not much difference at all. Yes I do have the 2-speed transfer case and believe it comes with the Z-71 package that way. The non Z-71 RST's have the 1-speed case if I remember correctly.

 

Do you know when your build date was?

Posted (edited)
37 minutes ago, Matty Patty said:

 

That's exactly what I was thinking! That the AAHD went to Indiana while the AAJF went South of the border to Mexico.

 

Not much difference at all. Yes I do have the 2-speed transfer case and believe it comes with the Z-71 package that way. The non Z-71 RST's have the 1-speed case if I remember correctly.

 

Do you know when your build date was?

Mine was made 11/2018. 

 

If trucks with production dates of may and June 2019 are still having the same issues, this is beyond just a small bad batch of axles. AAM really screwed up bad.

 

To follow up, I also checked my CV shafts again and I indeed do have the same movement that Limelight showed in his video on page 1 of this thread. Even my passenger side has a little play but not as bad as the drivers side.

Edited by Z06JPB
Posted

Hello- Chiming in on this thread after reading the last 30+ pages as I would like your guys Input.. I have a 2017 6.2 8 speed z71 ltz that I am currently in the process of lemon lawing due to the dreaded 8 speed drivetrain clunk , and it should be completed next week (a long and strenuous 4 month process). 

I recently ordered a ‘19 ltz 6.2 10 speed 4x4 to replace my ‘17 and it just arrived to the dealer (build date 7/22/19) - I had the dealer look up the axle and it unfortunately has the su4, I got under it to test it and the axle moves back and forth as the previous posts and videos describe. It’s brand new, drives perfect and is beautiful however this thread has me terrified to move forward with the purchase, as I do not want another lemon. I spoke with the sales manager and he mentioned that there is no way they can specifiy to request the gm su5 axle when ordering as it’s not part of a package and just basically up to chance as to what axle you get. So my question is- should I take delivery and hope for the best, re order and hope for the best, or look elsewhere ? 

Posted
31 minutes ago, LTZGTR said:

Hello- Chiming in on this thread after reading the last 30+ pages as I would like your guys Input.. I have a 2017 6.2 8 speed z71 ltz that I am currently in the process of lemon lawing due to the dreaded 8 speed drivetrain clunk , and it should be completed next week (a long and strenuous 4 month process). 

I recently ordered a ‘19 ltz 6.2 10 speed 4x4 to replace my ‘17 and it just arrived to the dealer (build date 7/22/19) - I had the dealer look up the axle and it unfortunately has the su4, I got under it to test it and the axle moves back and forth as the previous posts and videos describe. It’s brand new, drives perfect and is beautiful however this thread has me terrified to move forward with the purchase, as I do not want another lemon. I spoke with the sales manager and he mentioned that there is no way they can specifiy to request the gm su5 axle when ordering as it’s not part of a package and just basically up to chance as to what axle you get. So my question is- should I take delivery and hope for the best, re order and hope for the best, or look elsewhere ? 

In my opinion if you buy it there is a very good chance it'll develop this problem and you will need to take it in.

 

With that being said I think GM will get this fixed right eventually. At least I'm hoping.

 

So you have three choices,

 

Buy it knowing you'll more than likely have to take it in for the fix, buy a 2wd Silverado, or buy another full size truck. 

 

Only other full size truck I'd trust right now is the Tundra.

Posted (edited)

Did you guys see the bulletin I posted a few pages back?

 

It shows it was updated on 8/05/19.

 

Wonder if it's the new fix?

 

What do you guys think?

 

I just got ahold of that document yesterday from my dealership.

 

I'm supposed to get a call from a GM case manager next week. I want to make sure I don't get the old fix. I don't mind waiting as long as the new, hopefully permanent fix is applied.

Edited by Sin City Trail Boss
Posted
9 hours ago, LTZGTR said:

Hello- Chiming in on this thread after reading the last 30+ pages as I would like your guys Input.. I have a 2017 6.2 8 speed z71 ltz that I am currently in the process of lemon lawing due to the dreaded 8 speed drivetrain clunk , and it should be completed next week (a long and strenuous 4 month process). 

I recently ordered a ‘19 ltz 6.2 10 speed 4x4 to replace my ‘17 and it just arrived to the dealer (build date 7/22/19) - I had the dealer look up the axle and it unfortunately has the su4, I got under it to test it and the axle moves back and forth as the previous posts and videos describe. It’s brand new, drives perfect and is beautiful however this thread has me terrified to move forward with the purchase, as I do not want another lemon. I spoke with the sales manager and he mentioned that there is no way they can specifiy to request the gm su5 axle when ordering as it’s not part of a package and just basically up to chance as to what axle you get. So my question is- should I take delivery and hope for the best, re order and hope for the best, or look elsewhere ? 

Explain your concerns. Buy it only if the dealer throws in an extended warranty.  

 

Worth a shot. Worst they can tell you is no. Then you'll obviously have a decision to make.

  • Like 1
Posted
5 hours ago, fish_guru said:

Explain your concerns. Buy it only if the dealer throws in an extended warranty.  

 

Worth a shot. Worst they can tell you is no. Then you'll obviously have a decision to make.

Thanks for your reply. My concern is taking delivery of a brand new truck that has a manufacture defected front axle that up to today- no one has currently confirmed a repair for it. Reading this thread and hearing people expressing how terrible the problem is and how gm still hasn’t been able to fix it is what’s scary. My dealer said they can’t swap it for the gm su5. It’s disspaointing that gm would sell another brand new truck that comes with a faulty part- obviously being new it will have the warranty but the last thing I want is another truck that I will have to spend considerable time at the service center for them to again try fix something they don’t have a proper fix for. I essentially don’t want to get into another lemon, that is my concern- this current ‘17 I have has been terrible. It’s really a shame because I custom specd and ordered this new T1, it just arrived and is/drives so nice, but if at a couple hundred miles the axle will start jingling since it already moves back and forth with my hand test now, and I’ll have to take it in to service with no confirmed mend, then I mise well unfortunately pass on it. If there are any people who have the su4 axle that has movement under the hand test but haven’t experienced any jingle after some miles I would be interested to hear, I just wonder if all are affected or only a portion of the su4’s. 

Posted
1 hour ago, LTZGTR said:

Thanks for your reply. My concern is taking delivery of a brand new truck that has a manufacture defected front axle that up to today- no one has currently confirmed a repair for it. Reading this thread and hearing people expressing how terrible the problem is and how gm still hasn’t been able to fix it is what’s scary. My dealer said they can’t swap it for the gm su5. It’s disspaointing that gm would sell another brand new truck that comes with a faulty part- obviously being new it will have the warranty but the last thing I want is another truck that I will have to spend considerable time at the service center for them to again try fix something they don’t have a proper fix for. I essentially don’t want to get into another lemon, that is my concern- this current ‘17 I have has been terrible. It’s really a shame because I custom specd and ordered this new T1, it just arrived and is/drives so nice, but if at a couple hundred miles the axle will start jingling since it already moves back and forth with my hand test now, and I’ll have to take it in to service with no confirmed mend, then I mise well unfortunately pass on it. If there are any people who have the su4 axle that has movement under the hand test but haven’t experienced any jingle after some miles I would be interested to hear, I just wonder if all are affected or only a portion of the su4’s. 

I wouldn’t exactly call it “terrible”. It’s just annoying sometimes. I’m sure they will fix it. 

Posted
5 hours ago, LTZGTR said:

Thanks for your reply. My concern is taking delivery of a brand new truck that has a manufacture defected front axle that up to today- no one has currently confirmed a repair for it. Reading this thread and hearing people expressing how terrible the problem is and how gm still hasn’t been able to fix it is what’s scary. My dealer said they can’t swap it for the gm su5. It’s disspaointing that gm would sell another brand new truck that comes with a faulty part- obviously being new it will have the warranty but the last thing I want is another truck that I will have to spend considerable time at the service center for them to again try fix something they don’t have a proper fix for. I essentially don’t want to get into another lemon, that is my concern- this current ‘17 I have has been terrible. It’s really a shame because I custom specd and ordered this new T1, it just arrived and is/drives so nice, but if at a couple hundred miles the axle will start jingling since it already moves back and forth with my hand test now, and I’ll have to take it in to service with no confirmed mend, then I mise well unfortunately pass on it. If there are any people who have the su4 axle that has movement under the hand test but haven’t experienced any jingle after some miles I would be interested to hear, I just wonder if all are affected or only a portion of the su4’s. 

Okay here’s the deal. You can go back and read my posts on this thread for the last couple pages to read some history.

 

My SU4 has axle play, yes. I can move the axle in and out just like Limelight’s video on page 1, yes. 

 

However... I have determined that I do not have any noise coming from anywhere that I can hear while driving. By doing the physical inspection, I feared the worst and thought maybe I had not been listening closely enough.

 

Today I drove more than 70 miles and on the smoothest quietest newly paved asphalt roads with the radio and climate control off, I heard nothing. I ranged sustained speeds from 35 to 80 mph and heard nothing. I even switched on the Auto 4WD and 4HI to see if something changed or made a different noise but I couldn’t hear anything new. I even drove on some bumpy roads and potholes and listened for some axle clunk but still nothing.

 

The other thought I have is in regards to ambient temperature. GM describes the problem can get worse at higher temperatures. While I have drove a lot this summer during the hottest 90 degF days, today’s test was done in only 70 degF, cloudy weather. The road temperature had no sun load so it was relatively cool. I’m going to try and do another sustained driving period during a hotter, sunny day.

 

So, my SU4, while it exhibits the tell-tales that it should have a problem, is quiet as can be on the road. My truck now has a little over 3,100 miles on it so the jingle or clicking could still develop. My next experiment will be to go to the dealer and test trucks on the lot to see if the play is the same with other AAM axles. I really want to find an SU5 and test that as that may paint a better picture of what exactly is going on.

 

LTZGTR, your truck is such a late 2019 model that it is almost a 2020. I wouldn’t worry too much about the axle issue as your truck may already have an improved SU4 axle. Any chance you could get the part number off it? If it’s different from my AAHD and the AAJF axle part numbers, good chance it’s a fixed unit. 

 

The only way to ensure you get a truck with an SU5 is to take the VIN number to a GM dealer and have them print off the Vehicle Build Information Sheet off GlobalConnect. That will display all the RPO codes.

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