2007 Suburban 2500 124k Delo XSP 7000 mile OCI UOA

[cdm1993]

Got a UOA done for the family hauler. 70% short tripped during this OCI, mostly summer weather. 95F average outdoor temps with low humidity during the OCI. Mostly less than 3 mile trips, with occasional 30 mile highway drives, and a few 1000 mile round trip drives up I5. Suburban has 4.10 gears and 4L80e so highway RPMs are around 2700-3000 RPM. I wanted a 15w40 to deal with the fuel dilution, heat and short trips, and to clean the engine up a bit. This vehicle is 1 year new to us. What are your thoughts on the report, mostly the lead levels?

Thanks.

 

[Soft Cars]

I've seen some fantastic low wear numbers with Castrol GTX in those GM truck engines. The 10W-40 grade. I don't know why, but they seem to get along with that oil real well.

 

[fantastic]

I concur with Blackstones analysis & with a big heavy suv being short tripped might be why you see elevated bearing wear. I'd not worry about it too much since it's a vehicle that you need to use & we've seen some engines that shed a lot of wear metals but still last 200-300k miles. Everything looks very good overall. Iron, etc are a good chunk lower than the universal averages. I think you're doing everything right here.

I've seen some fantastic low wear numbers with Castrol GTX in those GM truck engines. The 10W-40 grade. I don't know why, but they seem to get along with that oil real well.

Brand has been proven to not correlate with wear.

 

[Soft Cars]

Brand has been proven to not correlate with wear.

I think viscosity matters more than brands. I've seen low wear with Chevron Supreme 10W-40 too. (GM truck engines)

 

[JavierH19]

6.0's still breaking in.

 

[OVERKILL]

I've seen some fantastic low wear numbers with Castrol GTX in those GM truck engines. The 10W-40 grade. I don't know why, but they seem to get along with that oil real well.

You cannot directly infer wear rates from PPM in a UOA.
Used Oil Analysis - Bob is the Oil Guy

During the last 50 or so years I have carried out hundreds of UOAs on all sorts of engine configurations – and on transmissions, gearboxes and differentials. These were done in consort with four Major Oil Companies (Shell, Exxon-Mobil, Castrol, Chevron-Caltex), my Employers, my Customers and on my own Fleet and other vehicles. Not once were they ever used to discriminate one lubricant from another on the grounds of wear metal uptake!

 

[Soft Cars]

You cannot directly infer wear rates from PPM in a UOA.
Used Oil Analysis - Bob is the Oil Guy

1. Passenger Car Motor Oil (PCMO) - Gasoline Vehicles
2. Used Oil Analysis - Gasoline

What I will do is add the used oil analysis forum to my list of forums never to post in. Not worth the hassle and I really don't care what oil people put in their cars anyway. The End.

 

[cdm1993]

I've seen some fantastic low wear numbers with Castrol GTX in those GM truck engines. The 10W-40 grade. I don't know why, but they seem to get along with that oil real well.

I’ll look for that next time I’m changing the oil.

I should add I changed the air filter after this OCI. It wasn’t in bad shape, looked like an Autozone filter, but I did notice it was pretty stiff. The Wix premium I replaced it with was much more malleable especially at the gasket. Maybe that will make a difference in SI reading. Does anyone else silicone paste the gasket to make a better seal in the filter base?

I also noticed these engines get to temp quicker. (run hotter…I know this isn’t empirical but from my 1997 k1500 with the 5.7, that engine is all iron from heads to block, and takes much longer to get to 210F. The LY6 seems to get to temp much faster…maybe due to aluminum heads?) I guess what I’m asking is due to the weight and operating conditions, is it worth sticking to a stout HDEO or just go with a 30/40 synthetic?

 

[cdm1993]

6.0's still breaking in.

I love this engine. No DOD, no AFM, iron block. Should last forever. I see them in UPS delivery trucks that GVWR over 20k. That says something about it’s reliability

 

[twX]

Does anyone else silicone paste the gasket to make a better seal in the filter base?

Silicone grease or sealant? Silicone grease may not be safe for oxygen sensors. There's a risk that grease could make it's way onto the MAF sensor as well. K&N makes a grease specifically for airbox sealing. I've used Permatex synthetic grease.

 

[cdm1993]

Silicone grease or sealant? Silicone grease may not be safe for oxygen sensors. There's a risk that grease could make its way onto the MAF sensor as well. K&N makes a grease specifically for airbox sealing. I've used Permatex synthetic grease.

Interesting. I’ve seen/read about using 3M Silcone paste (dielectric grease) to create a better seal.

 

[JavierH19]

I love this engine. No DOD, no AFM, iron block. Should last forever. I see them in UPS delivery trucks that GVWR over 20k. That says something about it’s reliability

I've got 337k on my 6.0 since new and I do extended 15w-40 drains using whatever's cheapest, only metal that's been replaced inside is the chain since that's a maintenance item long term as I snapped one once at almost 400k in a ford. no head gasket failure either. Still runs buttery smooth and quiet with identical power like when it was new. The 4l65e and the front and rear doffs and t case have also been bulletproof having only 4 fluid changes ever with nothing replaced.

 

[Snagglefoot]

Nice to see another 3/4 ton Suburban. I have a 2008 3/4 ton with a 6.0, 6L90, with 3,73 gears. The 6 speed has two gears that are overdrive and has a manual over-ride to select which gear to run at which gives a lot of flexibility when towing. I used primarily 5w30 Pennzoil Platinum but once I hit 200,000 miles I switched to Pennzoil Euro 5w40 in the summer and Pennzoil Euro 0w30 in the winter. I use Pennzoil because of the excellent rebates. It currently has 255,000 miles. I’m planning on replacing the oil pickup tube O ring this year as I noticed the rise in oil pressure at sub zero temps is a bit delayed. I suspect a brittle O ring. As far as the lead goes, I don't have a UOA but I would continue with your 15w40.

 

[cdm1993]

Nice to see another 3/4 ton Suburban. I have a 2008 3/4 ton with a 6.0, 6L90, with 3,73 gears. The 6 speed has two gears that are overdrive and has a manual over-ride to select which gear to run at which gives a lot of flexibility when towing. I used primarily 5w30 Pennzoil Platinum but once I hit 200,000 miles I switched to Pennzoil Euro 5w40 in the summer and Pennzoil Euro 0w30 in the winter. I use Pennzoil because of the excellent rebates. It currently has 255,000 miles. I’m planning on replacing the oil pickup tube O ring this year as I noticed the rise in oil pressure at sub zero temps is a bit delayed. I suspect a brittle O ring. As far as the lead goes, I don't have a UOA but I would continue with your 15w40.

Do you think the o ring lifespan is based on mileage or time? Or heat cycles? I want to get a pulse on when I should expect to do mine as well.

While down there, is it worth replacing the pump too? Or stick with OEM. Recently I have noticed it’s been hard to find OEM replacements, even from sources like Rock Auto, so I wouldn’t want to replace a working but used part with a new piece of junk.

 

[Snagglefoot]

Do you think the o ring lifespan is based on mileage or time? Or heat cycles? I want to get a pulse on when I should expect to do mine as well.

While down there, is it worth replacing the pump too? Or stick with OEM. Recently I have noticed it’s been hard to find OEM replacements, even from sources like Rock Auto, so I wouldn’t want to replace a working but used part with a new piece of junk.

Certainly you can get at the pump O ring by coming in from the front and installing a new oil pump. However, you have to take off the water pump and front cover. On a four wheel drive, (which mine is) it might be the way to go as it requires dropping the front axle a few inches if you come in from the bottom and take the oil pan off. I would like to see the opinion of other bittoggers on which way is best. What say other LS high mileage owners?

 

[Artem]

It’s the constant short trips that cause more scraping between metals.

Cold starting the 15w40 every time probably isn’t helping either.

 

[Snagglefoot]

Here is a video on getting the front cover back onto an LS engine. The engine is show upside down. Notice the mechanic uses a few alignment tools to get it right.