CHECK YOUR DIFFS...

shadow gray 2020 hd · April 10, 2023

Thank you to the op on this thread. Never would have known mine was low. Will definitely be bringing this up with the dealer when I am there on Friday for my rear spoiler/window leak.

Pryme · April 10, 2023

On 4/9/2023 at 3:34 PM, shadow gray 2020 hd said:

My front diff is fine, but back is low enough that I couldn't even touch it with my pinky. Pretty ridiculous on a truck bought brand new with only 20,000 miles on it to be low. I am sure it was low from the factory because it sure hasn't leaked. Yet another GM failure on the truck I bought brand new. Very disappointing. Guess I will be driving into town tomorrow morning and buying a couple quarts of gear oil, or should I take it to the dealer? With it being under warranty still, the dealer has done all the service work and oil changes, don't guess they check diffs when they do their multipoint inspection?

No idea how low it is, after reading another thread in here, hoping no damage has been done to it.

From what I’ve read on here they come pre filled from AAM.
mine was about half a quart low and I had no metal dust at all in my plug or that I could really tell in the fluid. But I also only went 4,400mi on mine being half as low as yours.

Have you topped up your front end zerks? A lot of us have had to because they ship them low.

I would have taken mine to the dealer and told them to top it off but I don’t like to be annoyed by service people as I’ve found they usually are and I planned to put in Amsoil anyway so just did mine myself.

Pryme · April 10, 2023

10 hours ago, DuckBoi said:

My 23 has a drainplug for the rear diff. Perhaps you got a defective diff cover?

The drain plug is not in the diff cover sir. It would be located on the very bottom of the actual differential housing.

if you have an actual drain plug on the very bottom on your 23, you’re lucky. Not sure why there is such a discrepancy on this.

shadow gray 2020 hd · April 10, 2023

9 minutes ago, Pryme said:

The drain plug is not in the diff cover sir. It would be located on the very bottom of the actual differential housing.

I will have to look closer at mine to see.

12 minutes ago, Pryme said:

I would have taken mine to the dealer and told them to top it off but I don’t like to be annoyed by service people as I’ve found they usually are and I planned to put in Amsoil anyway so just did mine myself.

I probably should have, but didn't feel like waiting on them.

13 minutes ago, Pryme said:

Have you topped up your front end zerks? A lot of us have had to because they ship them low.

The only one I was aware of that was an issue was under the skid plate, and yes I have. Good reminder, I need to again, because I doubt the dealer has. Where are the others of concern?

Pryme · April 11, 2023

12 minutes ago, shadow gray 2020 hd said:

I will have to look closer at mine to see.

I probably should have, but didn't feel like waiting on them.

The only one I was aware of that was an issue was under the skid plate, and yes I have. Good reminder, I need to again, because I doubt the dealer has. Where are the others of concern?

There are 9 total zerks to grease. There was a good video I found on YouTube showing them all. I’ll see if I can find it. They used to have 11. Now only 9.

Pryme · April 11, 2023

20 minutes ago, shadow gray 2020 hd said:

I will have to look closer at mine to see.

I probably should have, but didn't feel like waiting on them.

The only one I was aware of that was an issue was under the skid plate, and yes I have. Good reminder, I need to again, because I doubt the dealer has. Where are the others of concern?

Here is the video I used to easily find mine. This is a diesel and a little older but they are in the same places. This video was just clear showing them.

customboss · April 13, 2023

On 3/27/2023 at 8:36 AM, Black02Silverado said:

I always change mine over to AMSOIL right away. These Easy Packs make it nice and clean to do.

YES! Second that motion did a drain refill last week on transfer case of trail boss custom and I run the heck outta that auto,4WDhi and 4WDlo in weather at altitude here ( 7800 -11000' msl). The amsoil that I changed out at 22,500 miles of use was so clean I did not sample it. Transfer case uses DEX6 I replaced OEM fill at about 6400 miles with Amsoil ATL and its been flawless. I am in water, snow, ice etc. Diffs will not be checked or changed for another 30000+ miles easy.

diyer2 · April 13, 2023

I was not going to pay for Amsoil products for years. Now well worth the money.

shadow gray 2020 hd · April 13, 2023

On 4/10/2023 at 6:44 PM, Pryme said:

The drain plug is not in the diff cover sir. It would be located on the very bottom of the actual differential housing.

Just crawled under mine again this afternoon, and confirmed my differential does have a drain plug. Slightly to the driver side of center. I think I had a little gear oil on my hands when I filled it the other day. Does not appear to have any leak that I can tell.

Pryme · April 14, 2023

5 hours ago, shadow gray 2020 hd said:

Just crawled under mine again this afternoon, and confirmed my differential does have a drain plug. Slightly to the driver side of center. I think I had a little gear oil on my hands when I filled it the other day. Does not appear to have any leak that I can tell.

Yeah mine is just the flat blank spot where a bolt should be. I was jiped

shadow gray 2020 hd · April 15, 2023

On 4/10/2023 at 7:19 PM, Pryme said:

Here is the video I used to easily find mine. This is a diesel and a little older but they are in the same places. This video was just clear showing them.

I can't get my lower ball joints on either side to take grease. Tried two different guns, and put as much pressure on the head to the zerk as I could, and grease just made a total mess all over the top. My lock on coupler won't fit that zerk. And no way the dealer had hit any of them when I had it in for oil change/service.

Pryme · April 15, 2023

5 hours ago, shadow gray 2020 hd said:

I can't get my lower ball joints on either side to take grease. Tried two different guns, and put as much pressure on the head to the zerk as I could, and grease just made a total mess all over the top. My lock on coupler won't fit that zerk. And no way the dealer had hit any of them when I had it in for oil change/service.

You sure it doesn’t have junk on it and/or it’s not seated on the zerk? Try and push it hard onto it.

shadow gray 2020 hd · April 16, 2023

13 hours ago, Pryme said:

You sure it doesn’t have junk on it and/or it’s not seated on the zerk? Try and push it hard onto it.

They are clean, don't look to have ever been greased. I am going to try to heat them up a little and try again.

64BAwagon · April 16, 2023

The lower ball joints are tricky. There is almost no clearance and a locking coupler is definitely not going to fit. I have found that turning the wheels in the opposite direction from the one your greasing (turn right for left side and vice versa) will give you a better view of the fitting. I doubt that they are stuck, its more likely an issue with aligning the fitting with the coupler.

Sadly its common for oil change places to skip these due to the difficulty. Unless you get under it and check youre never going to see it until its too late and you have to replace a ball joint prematurely.

We had an older Colorado at work that required removal of the front wheels to grease, straight up bad engineering.

Edited April 16, 2023 by 64BAwagon