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Posted
10 minutes ago, PunchT37 said:

Correct. That`s why GDI is here to stay. Catch cans or not.🙂

 I could get comfortable with this technology if they would just move the high pressure pump out of the freaking crankcase. Fire is fire. Matters not where but gas in the oil at these levels is silly. When the pump seal lets go that dilution rate is 8% or more and will kill viscosity one to two full grades in a heartbeat. No favors done for lubricity either. 

Posted

Thanks for all the good info on this forum.  I've got a 2023 and just changed the oil at 25k.  I've been using pennzoil, just always have.  Been changing it every 5k and pretty much every time it's burned about 1 qt.  This time I used Valvoline restore and protect and will see if it makes a difference.

  • Like 1
Posted
33 minutes ago, Philip LaLone said:

Thanks for all the good info on this forum.  I've got a 2023 and just changed the oil at 25k.  I've been using pennzoil, just always have.  Been changing it every 5k and pretty much every time it's burned about 1 qt.  This time I used Valvoline restore and protect and will see if it makes a difference.

I would bring it down to 4 to 3000 mi oci.

  • Like 2
  • 3 weeks later...
Posted (edited)

Ok boys, just went in for service and tires at 85,786 kms (53,316 miles) and tech noticed 'oil leak passenger side of engine'. I remember reading from about page 100 onward so betting it's one of these things. It goes back in Thursday for diagnosis and fix, under factory powertrain warranty to 100,000km, I do have extended to 160,000 kms (with deductible) but we're still on factory warranty. I'll update of course to add to the collective database.

 

I just did a round trip for work that was 2516 kms or 1564 miles and average economy was 11.6 l/100km (20.3 mpg) so consistent with new (4" lift, no chin spoiler, 33x10's, 900 lbs over stock with fuel tank/tools/gear), much of that trip off pavement roads into remote mine site end of road north type trip), haven't noticed oil consumption between 5000 km oil changes but haven't really checked either and nothing is on the ground under truck when parked so must just be some visible oil the tech saw but not a big enough issue to be noticed by ground or 5000 km service intervals. I run Petro-Canada 87 octane (feels happy and quick), live at 4000' and play a lot between 2500' and 5000', and I pull a 3000 lb trailer primarily, especially since about the 50-60,000 km mark when I added a commuter vehicle, except the odd long work trip I'll take this truck without trailer for it's hwy comfort over the commuter. 

 

Any guesses to what this issue will be? Maybe we can offer a prize to the correct guess? A jr g-man badge maybe? 😉

Edited by 4banger
  • Haha 1
Posted
1 hour ago, 4banger said:

Ok boys, just went in for service and tires at 85,786 kms (53,316 miles) and tech noticed 'oil leak passenger side of engine'. I remember reading from about page 100 onward so betting it's one of these things. It goes back in Thursday for diagnosis and fix, under factory powertrain warranty to 100,000km, I do have extended to 160,000 kms (with deductible) but we're still on factory warranty. I'll update of course to add to the collective database.

 

I just did a round trip for work that was 2516 kms or 1564 miles and average economy was 11.6 l/100km (20.3 mpg) so consistent with new (4" lift, no chin spoiler, 33x10's, 900 lbs over stock with fuel tank/tools/gear), much of that trip off pavement roads into remote mine site end of road north type trip), haven't noticed oil consumption between 5000 km oil changes but haven't really checked either and nothing is on the ground under truck when parked so must just be some visible oil the tech saw but not a big enough issue to be noticed by ground or 5000 km service intervals. I run Petro-Canada 87 octane (feels happy and quick), live at 4000' and play a lot between 2500' and 5000', and I pull a 3000 lb trailer primarily, especially since about the 50-60,000 km mark when I added a commuter vehicle, except the odd long work trip I'll take this truck without trailer for it's hwy comfort over the commuter. 

 

Any guesses to what this issue will be? Maybe we can offer a prize to the correct guess? A jr g-man badge maybe? 😉

 

 

Sounds like it could be from that PCV separator as it sits on the passenger rear side of the head.  

  • Thanks 1
Posted
3 hours ago, newdude said:

 

 

Sounds like it could be from that PCV separator as it sits on the passenger rear side of the head.  

Well I climbed over the engine couldn't see anything suspect, then got under front end and still nothing but peering back I could see shine off my new oil filter, so then went in under passenger side to oil filter and definitely some seepage going on that side and what appears to be below block where anything wet can be found and only one side of the oil pan looks like it gets any, and yet nothing hits the ground, a drop forming on the oil filter.

 

And now I'm recalling my service guys said sometime ago they noticed oil pan sweating and would keep an eye on it over time, I do have the refresh power but still the older black plastic oil pan and recall hearing newer ones were coming with aluminum oil pans, so here's hoping that's what the issue is. I can't see anything higher up from this quick look at things. 

 

Will update when I know more on Thursday. 

  • Like 1
Posted

Ok, just got the call, 'front engine cover' is what appears to be leaking, bunch of parts/seals ordered, will be a few weeks, once that's done they can then confirm if anything else like oil pan. Since it's slow leak will be driving it until parts are in one of which is direct from usa which is the culprit to making this a few weeks away. Will take it from there and update when it's done.

  • Like 1
  • 1 month later...
Posted
On 5/31/2025 at 3:14 AM, silveradosid said:

how mant miles did you drive with the intake tube off

Sorry for late reply!  Only about 1 mile. 

 

Also, just read past 3 pages. Im due for an oil change in about 1500 miles. it will be the 4th one. 1st two were dealer oil changes. Last one I noted 1qt low at 5K change. I used Mobil 1, be interested to see how this one goes, but Im gonna try the restore and protect this go around. If it burns a bit less and helps protect. Im all in as it shouldnt have much deposits at 20K yet. 

 

I wanted to ask your guys thoughts on a catch can. I know J&L makes one, but its a bit of a PITA to install. 

Posted (edited)

Ok, so we have couple things to update on. 
 

1. they swung and missed on my oil leak with that front cover business. Put some miles on and did a trip with trailer let em check again and goes back in Friday for new oil pan and gasket as attempt #2 to figure out the oil leak. I mentioned the poly vs aluminum oil pan but looks like same type going back on. Shrug.

2. On the trip coming home with my little trailer threw codes climbing a good hill and lost power, could still maintain a little above 60 mph but like lost boost as engine had to roll much higher rpms near or at redline on anything less than flats. So credit she got me home but have new one. 

 

So they pulled codes when back and apparently there’s a bulletin and gm aware of issue but no apparent fix yet. Mass air flow related codes. After it was at home and sat for days the next start the engine light was out. So feels like normal again but just a bit of back and forth to dealer without trailer so can’t really tell.

 

Had anyone else heard about this yet? Can anyone verify this bulletin?

 

just under 90,000 kms now so just under 56,000 miles

 

starting my 3/4 ton gas v8 research now lol😉

Edited by 4banger
  • Sad 2
Posted (edited)

Interesting my 2022 custom trail boss L3B made it over 70,000 miles with only the emissions vent pump  failure. Never any leaks, no oil control issues. It would use oil but only when injectors got dirty from the crappy fuels we have to choose from and using Amsoil PI 3000-5000 would clean them enough the oil usage would slow. In 5000 miles it rarely used a whole qt. 
 

Edited by customboss
  • Like 1
Posted
On 10/18/2025 at 4:56 PM, 4banger said:

Ok, so we have couple things to update on. 
 

1. they swung and missed on my oil leak with that front cover business. Put some miles on and did a trip with trailer let em check again and goes back in Friday for new oil pan and gasket as attempt #2 to figure out the oil leak. I mentioned the poly vs aluminum oil pan but looks like same type going back on. Shrug.

2. On the trip coming home with my little trailer threw codes climbing a good hill and lost power, could still maintain a little above 60 mph but like lost boost as engine had to roll much higher rpms near or at redline on anything less than flats. So credit she got me home but have new one. 

 

So they pulled codes when back and apparently there’s a bulletin and gm aware of issue but no apparent fix yet. Mass air flow related codes. After it was at home and sat for days the next start the engine light was out. So feels like normal again but just a bit of back and forth to dealer without trailer so can’t really tell.

 

Had anyone else heard about this yet? Can anyone verify this bulletin?

 

just under 90,000 kms now so just under 56,000 miles

 

starting my 3/4 ton gas v8 research now lol😉

When my intake tube came off lol.

 

I would think check for any gaps or anything there first..

  • 1 month later...
Posted

my 2020 has started throwing code p2c9b for the turbo. it only does it if the temperature is below freezing.first start of the day it triggers the code, i can clear the code and it is fine for the day. any ideas

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