Why am I using oil with Mobil 1 HM 5w 30

Joined
Jun 10, 2019
Messages
1,371
Location
FL
I have owned my Tahoe for 205k miles.
Put in Mobil 1 HM 5w 30 after 1500 miles Im halfway down on the hash marks. Supertech 5w 30 HM burned that in 4000k miles. Only other oil that burned very fast in my truck was valvoline 5w 30 full syn, 2 quarts low. Yes 2 quarts back 10 years ago about 4000 in to my oil service my low oil light came on. All other oils serviced well even valvoline HM. Now I noticed Mobil 1 HM 5w 30 burning. This is thicker than all others ai expected no burning.
 
It's common for a change in chemistry to result in some consumption. Usually it tapers off, but if it doesn't, I'd suggest switching back to whatever didn't consume.
 
You're down in FL, why not try a 10W30 or a 15W40 in Supertech or whatever you want? The temps are warm enough you won't have any oiling problems with a numerically higher W rating, and when your truck is "cold" the 10Wxx or 15Wxx will be thicker than your current 5Wxx, and "may" help reduce usage if it's mainly happening during startup before the block, pistons, and rings expand a little at operating temp. Once the truck is all warmed up there will be miniscule, if any, difference between a 5W30 and 10W30 viscosity, so no negatives from that point.

Or just go back to Supertech 5W30 and dump a half a quart in every 4 million miles like you did before.

I tried but I couldn't resist the 4000k mile typo above :)
 
You're down in FL, why not try a 10W30 or a 15W40 in Supertech or whatever you want? The temps are warm enough you won't have any oiling problems with a numerically higher W rating, and when your truck is "cold" the 10Wxx or 15Wxx will be thicker than your current 5Wxx, and "may" help reduce usage if it's mainly happening during startup before the block, pistons, and rings expand a little at operating temp. Once the truck is all warmed up there will be miniscule, if any, difference between a 5W30 and 10W30 viscosity, so no negatives from that point.

Or just go back to Supertech 5W30 and dump a half a quart in every 4 million miles like you did before.

I tried but I couldn't resist the 4000k mile typo above :)
Haha 4k
 
To answer your question posed in this string's title: Your valve guides and/or rings are now too worn, or your valve stem seals are too roasted to be helped much by the additional seal conditioners in your HM oils. You can keep adding oil, or rebuild the worn/tired bits.
 
Did you check the oil after letting the engine get hot and sit overnight? That gives you the most accurate level. I noticed the oil level is halfway down the hash mark in my LS1 if I only let it run after a cold start for a few seconds and shut it off, even if it sits overnight. If the oil is hot, it somehow drains back into the pan better. Same thing happens in the Hemi.
 
Supertech 15w40 at $9.xx/gallon works well in everything I used it in... From 30+ year old V8 engines, to modern GDI and turbo engines. If your climate allows - it's a good budget all-fleet oil. Or if budget is not a concern - Mobil1 FS 0w40, many on this forum claimed decreased oil leakage and consumption with it.
 
I use Euro 0w-40 or 5w-40 oils in my comparable Suburban with 300k miles. Had minor consumption with 5w-30 and 10w-30.
 
Different brand and different engine but I have a 1998 Ford Explorer Sport with a SOHC 4.0L V6 that I recently inherited that has nearly 300,000 miles driven primarily on 5w30 or 10w30 in warm weather states. Now it is going to have to live in the frigid frozen tundra of Wisconsin this winter, I am putting M1 0w40 in soon without any second thoughts. The engine is not consuming oil but I do think it best to compensate for the engine wear by using a heavier oil that the recommended 5w30.

If you are in Florida you can easily get away with using an Xw-40 oil of your choosing. Perhaps even consider an Xw-50 if you feel so inclined.
 
If you are in Florida you can easily get away with using an Xw-40 oil of your choosing. Perhaps even consider an Xw-50 if you feel so inclined.
SuperTech 20w50 is only $12.96/5qt jug at Wal-Mart. According to the writings on the bottle it is actually recommended in turbocharged applications, as well as naturally aspirated, and being SN Plus rated I'm pretty sure it is more of a semi-synthetic now than a conventional. Good value for anyone looking for a 20w50, such as Evo guys...
 
Back
Top