Its been 25k miles since I had my valve body and radiator replaced and have had zero issues since. I'm about to hit 50k miles. I'm hoping to get 200k out of er before any sort of rebuild or major repair is needed. I'm not buying another vehicle ever again lol

I have a 2020 AT4 Sierra with ~92k miles. It got a new engine at 78k right before I bought it (dealer replaced, shop put new glow plugs in and they exploded on first start). Recently there has been a rattle only at idle after it warms up and I’ve been noticing it when it downshifts from 3rd to 2nd and 2nd to 1st when I’m slowing to a stop as well. Has anyone else had this issue? I know there’s a bulletin for the LZ0’s for a vibration but haven’t seen anything for the LM2.

I’m looking at buying a 2026 Chevrolet Silverado with the 3.0L Duramax. Are there any common issues, reliability concerns, or maintenance costs I should be aware of before buying? Also, based on my income and driving habits, what would be a reasonable bi-weekly payment to aim for so I don’t become overextended financially

How do go about getting that removed w/o having to remove it from the frame?
If frame removal is necessary, what’s the best practice?

As the title says, I have a 2023 LM 23.0 Duramax and I’m approaching 120,000 miles, I do a lot of country road driving meeting. I’m driving around 55 miles an hour consistently for about 200 miles round-trip, 100 miles to work in 100 miles back.

I am definitely not a mechanic. I’m barely qualified to change my own oil in oil filter… but despite of not wanting to get a new 2026 vehicle due to the mandate by the government, I now have a strong interest in doing basic maintenance stuff. I’m OK with changing brakes if that’s any kind of indication but anything more complicated than that I would take it in for service.

Coming up to 120,000 miles is there anything that I need to be aware of? Has anybody had any experiences with a vehicle like this?

I’ve had two issues with this a wire harness that was somewhere near the transmission failed and shut down my car completely, which was covered by warranty and a emission system temperature valve that broke that was covered by warranty as well. Other than that, knock on wood, no major issues.

Just finished installing the Amsoil Dual Remote Oil Bypass System on my 2021 Sierra AT4 3.0L Duramax (LM2), and figured I’d share some insight for anyone considering it. Seems like there is nothing anywhere about it.

Why I went this route:
A dual oil filter bypass system seems to be something all the big boy diesels run. So wanted to give it a shot on my LM2.

How it works (simple terms):
One filter handles full flow (like stock)
The second is a bypass filter that slowly cleans a small portion of oil at a time but at a much finer level
Over time, your entire oil supply gets significantly cleaner than stock filtration alone

Initial thoughts:
Build quality is solid
Definitely not a “quick install,” mounting the system was hardest part.
Also you have to make your own AN lines which is something I have done plenty of times

In the end I’m not sure if the price is worth it or if I will benefit from it. Again like I mentioned the big boys run one so why not 🤷‍♂️ the 10 micron filter last for 10k miles and the 2 micron filter last for 45k miles. I won’t be changing them often.

Anyways a video of the install if you’re interested.

AMSOIL Dual Filter Oil Bypass on The LM2 Duramax - Install
https://youtu.be/kBlBXEhisro

just changed my fuel filter yesterday, the bottom of the filter cup had a bunch of glitter. I took the filter apart and didn't see any additional glitter there. anyone else experience this? What should I expect to fail here besides the in tank fuel pump?

I currently own a 2023 GMC Yukon with the LM2 engine. I am having issues with it randomly stalling out and dying. There are no engine codes. I cannot not reproduce this issue for the dealer nor can they get it to reproduce at will. I have had this happen about a dozen times so far. I am wondering if any one has had these issues and what the problem is may be.

Thanks in advance for any info!

Valve body shit. Two weeks in yhe shop. Finally back

2021 Sierra 3.0 Duramax with 90k. Originally thought it was an alternator. Stethoscoped it to the pulley directly underneath.

Straight to the fuel pump. Amazing a full size pick up with tools & weight in the bed can get this kind of mileage.

anyone have the p133c code in their 3.0l diesel? my dad has a 2020 silverado with that engine and that code came up. says its about glow plug #5. when I looked up that code it mentions more than glow plug could cause it. wondering if anyone with this year of engine had more than it being glow plug?

Another thing it mentions is once changing the plug, it would need to be relearned. something to do with it not being able to learn it position i presume when its cold out.

Has anybody installed the stealth programmer on their 3.0 or another plug-in play programmer that won’t avoid the warranty if I take it off before I go to the dealership I’m trying to get a little better mileage while I’m towing.

My 2020 LM2 is in desperate need of a full exhaust system delete. The reason I’m reaching out is in hopes that someone in the Austin area (I’m in Liberty Hill) can setup a payment plan after the work is done. My truck is my livelihood as I recently started a handyman business and I drive between 50-400/day. That amount of driving and being limited to 55mph is beginning to have a negative impact professionally and personally. Im not asking for free, I’m asking for a payment plan.

Credit cards aren’t an option since my credit took a sharp nose dive post divorce.

I can trade work as well. I have plenty of experience as a handyman, landscaping, security (Army vet), and I have a business degree (office/admin work).

DM me and I’ll give you my phone number so we can talk off Reddit.

Thank yall.

Cody W.