2022 Suburban 3.0 duramax oil consumption

EngineNoO9 · September 11, 2022

Bought a brand new 2022 suburban with the 3.0 duramax in July and we’ve had major oil consumption issues. At 1500 miles it was down 4.5 quarts and the low oil pressure code got thrown. Initial assumption was the dealer may have forgotten to check oil at the pre delivery inspection. Did an oil consumption test and at 700 miles we were at 2.5 quarts down. Dealer is working with GM and they replaced the camshaft housing cover even though it already has the “updated” one. It also fried the number 2 glow plug which was replaced.

The service director seems doubtful that the “fix” Will correct the issue. From what we’re being told they haven’t seen this on the corrected camshaft housing covers. Our dealer had never even replaced one before. If it fails the next oil consumption test we’re likely looking at buyback. I told them I don’t want a new motor. Not for as much as this cost. I’d rather start over at zero.

Anyone else see this level of oil consumption? We love the diesel and will likely get that option again. Just frustrated with this one.

Denali Driver · September 11, 2022

Hi, That sucks to hear the Duramax is experiencing the same issue a the gas engines. I've run into other Duramax owners who are trouble free.

Does the diesel engine disable cylinders (Dynamic Fuel Management) while on the highway like the gas engines? I had a similiar experience (alarm) on my 5.3 but not until @ 46000 kms.

My dealer thinks maybe my piston rings are not in the right place on a couple cylinders but i doubt it. I just might go ahead and get this DFM disabled because a few of my spark plugs get badly fouled and the others are normal.

Good luck, I'll follow this thread.

EngineNoO9 · September 11, 2022

My ‘07 avalanche with the 5.3 has 210,000 miles on it and maybe burns a qt every 5000 miles. Mostly if I heavy highway drive. It is what it is.

The diesel doesn’t have AFM. They seem to be grasping at straws though the thought is there’s something with the PCV. Maybe…

Edited September 11, 2022 by EngineNoO9

redwngr · September 11, 2022

Some service advisers are idiots.

Remember that their job is just to confirm customer info and pass symptoms / requests to the folks in the shop.

Some seem to like to tell 'stories' cuz they think it makes the customer happy....

I've put about 26,000 on mine and am on the list of completely satisfied 3.0 owners.

EngineNoO9 · September 12, 2022

we’ve had 3400 trouble miles with multiple CELs but all related to the same issue. Driveability and mileage has been great.

Not really following what you’re saying about stories. As an engineer the PCV seems to be the only thing that makes sense but that’s us just bs’ing cause both parties are frustrated. They’ve had to bend over backwards to try and help us out in a vehicle that shouldn’t need any work. They want to avoid a buyback as much as we do but I also draw a line in the sand with a full motor swap on a vehicle this new that I paid that much for.

Talking with the Service Director (2nd only to the GM), he’s been very up front to us. The techs had never done this job before and have definitely never engine swapped. Doesn’t make me feel warm and fuzzy. Unfortunately the engineers at GM aren’t saying anything either but it appears that whatever is wrong in our specific motor is definitely a fluke.

mark1968 · September 12, 2022

We have a 2020 GMC Sierra 1500 with a 3.0 and at 28k miles I noticed the oil dropping quickly after oil changes (note i only noticed this as i checked my oil before/after a long trip- no warnings or codes thrown). I took it to our dealer and they found a TSB on certain serial numbers that were produced where they said this could be an issue with the camshaft housing and mine was in the range, so we did an oil test. Same result - oil dropped quickly so the truck has been in since last week getting the same fix that is mentioned above. I am hopeful this will fix the issue however based on the fact that now im hearing/seeing 2022’s with the same issue, that is concerning as the dealer mentioned that this issue was limited to a group of engines that were produced. Oh well, if it keeps being an issue after fixed, ill just trade it in on a new one as we love this truck and this engine despite this issue.

(And to answer the question in the first post, yes we have the same amount of oil disappearing and i don’t believe our dealer either has done one of these fixes. I was lucky as initially the dealer was mystified by this but apparently a GM tech was in the shop the day i brought the truck in not showing any oil on stick after the dealer had just changed the oil 2k miles before and he knew about the TSB on this.)

Edited September 12, 2022 by mark1968
Added more info

EngineNoO9 · September 12, 2022

Ours has the updated camshaft housing and they replaced it with the same exact one. They’d said they were hoping for a leak as that’s be easier to explain. The glow plug issue was tied to the camshaft housing cover TSB. Glow Plug #2.

mark1968 · September 16, 2022

So i just got my 2020 back with the new/updated camshaft and glow plug replaced and tomorrow we take off for another 2k mile trip to see how it does. Ill be frequently checking the oil level on the entire trip and crossing my fingers.

newdude · September 16, 2022

On 9/11/2022 at 11:54 AM, EngineNoO9 said:

Bought a brand new 2022 suburban with the 3.0 duramax in July and we’ve had major oil consumption issues. At 1500 miles it was down 4.5 quarts and the low oil pressure code got thrown. Initial assumption was the dealer may have forgotten to check oil at the pre delivery inspection. Did an oil consumption test and at 700 miles we were at 2.5 quarts down. Dealer is working with GM and they replaced the camshaft housing cover even though it already has the “updated” one. It also fried the number 2 glow plug which was replaced.

The service director seems doubtful that the “fix” Will correct the issue. From what we’re being told they haven’t seen this on the corrected camshaft housing covers. Our dealer had never even replaced one before. If it fails the next oil consumption test we’re likely looking at buyback. I told them I don’t want a new motor. Not for as much as this cost. I’d rather start over at zero.

Anyone else see this level of oil consumption? We love the diesel and will likely get that option again. Just frustrated with this one.

I don't think you are consuming it. At that rate of loss, its leaking.

Have them inspect the rear main seal as they are a known oil leak point on the LM2.