What oil does a 4.3 vortec like the best?

[paulo57509]

I have no idea of how to judge what and an engine "likes".

I've been using Pennzoil Conventional 5w30 since new ('03 GMC Safari) and switched over to Pennzoil Platinum 5w30 at 115k.

No worries.

 

[MileHigh18]

Originally Posted By: addyguy
Pennzoil Conventional 5w30 or 10w30 would be a great choice...this engine seems to like the high moly.
JMO....


I have a 4.3 Vortec in my Trailblazer, and it runs so freakin' smooth on Pennzoil Conventional 5w30.

 

[Brent_G]

The 4.3 like oil, and as long as it has some it will be a happy 4.3.

 

[CJE]

I just replaced a 2005 4.3 at 176,000 miles. I am the second owner and I knew the meticulous first owner. He had lost an oil pump and a timing chain during his tenure. For a good while it had a broken or weak valve spring that would dramatically limit the performance at 94 mph. Various other operating issues, low -ish compression all around and finally #6 showed 10-12 psi compression. I pulled the plug at that point and replaced the original engine with a $500. used engine from a yard I trust.

So apparently there is at least one which refused to run forever.

The rest of the truck is nice but the original 4.3 engine wasn't quite up to par somehow.

CJE
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Originally Posted by 901Memphis
I think the 4.3 is the exception, it runs forever on anything, any flavor. I don't think i have seen one of these engines that didn't outlast the rest of the truck.

I think recommending any API SN 5w30 is appropriate.

 

[Zaedock]

You pushed an engine with a broken / weak valve spring with 176K on the ticker to 94MPH and it's the engine that isn't up to par?

 

[farrarfan1]

Why resurrect a thread that's almost 7 years old?

 

[Zaedock]

Originally Posted by farrarfan1
Why resurrect a thread that's almost 7 years old?


HA! Just noticed. Didn't have my glasses before.