Certainly get some 40 or 50 grade in there. 15w-50 Mobil if you're normally above 20F. 15w-40 HDEO next. What are you thinking?
Running heavier oil than spec
- Thread starter Shannanigans
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Hard to say without looking at it
Hard to predict. I've seen engines in horrible condition continuing to run. They may consume oil or have lots of blow-by or smoky exhaust but still running. Those 4.3 engines were awesome. I have a 1994 4.3. they did tend to shed lots of iron that had you not had the magnet drain plug you may not have realized
4wd
$50 site donor 2026
Had a 2005 - ran Mobil 1 5W-30 or Delvac 15W-40
Many of them live long lives on the road and water …
Many of them live long lives on the road and water …
My 2000 Chevy Express with the 4.3 Vortec came with the magnetic plug for the engine oil drain.
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What would you recommend for an engine flush? And thanks!
rub on fingers is is smooth and silky or gritty
also if sludgy and over 10K on oil change could just ne ? normal?
I'd add a half qt of Marvel Mystery Oil to the last 500 miles of your present oil change interval (so no more than 1/2 qt over full) and then change it using a full qt of MMO with the rest a 15w40, like Delvac 1300, for another full interval or about 2500 miles anyway ...and then, if no apparent issues, start using Valvoline Restore and Protect 5w30... adjust as you go along...
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I'll do that tomorrw! Thx, and stand by....
How many miles on that OCI? An engine with 200K miles on it shouldn't be generating that much normal wear, so something might be going on. Did you cut open the oil filter to see if there were any larger particles, or look in the drain pan? That debris on the drain plug is most likely just "black paste" like ferrous debris. Run the xW-40 oil and monitor on the next oil change.
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Unknown OCI because the truck is new to me. Hopefully it the black paste you speak of. My plan is to change the oil again at a few hundred miles and monitor the plug and "feel" of the oil. These 4.3l Vortecs are usually solid and run for a long time. It was the first time I had seen anything like that on my drain plug, so pretty surprising and a little worrisome. I will definitely open the filter....I had planned on doing that by my roommate tossed it.
Thanks. Is there any oil treatment you would recommend? I don't know if cleaning out the sludge would be a good idea as it might precipitate an oil leak. Basically has no leakage now.
You can run Restore and Protect for 3-4 oil changes, or the most aggressive oil flush I have used successfully is 505 CRO by ATS Chemical. It's expensive if you don't buy it quantity, but BG makes a good oil flush too.
You're probably not going to push the engine real hard, so I'd just run 5W-30 Valvoline Restore and Protect and see how that does. What was the main reason why you wanted to go to a xW-40 grade ... just to help mitigate wear? If that wear is from something viscosity isn't going to help (like a cam lob or lifer, etc going), the thicker oil won't buy much extra time. Too bad Valvoline hasn't put the 40 grade VRP on the market in the USA yet, but hear it's coming sometime.
