Best Conventional Oil
 

Hello All. We just finished my turbo build and my mechanic is old school and insists that I use conventional oil in my engine or he will void the one year warrantee he is giving me. Basic specs: built bottom end with forged internals and some basic head work with upgraded valve train. S3 turbo kit. Making 247 on 12 lbs. on a mustang dyno. Car driven in a sprited fashion frequently and often; in the mountains and autocross.

The 10-30 Valvoline is looking like crap after the dyno session and about 800 miles(post break in period). Is there any conventional oil that you would trust in your cars? Should I be using some kind of conventional race oil? Is there such a thing?

I would really like to use Mobil One 0-40 but he is just not having it.


Thanks in advance.

Castrol GTX is the best conventional I've ran with the rotary. It's the only conventional I trust at this point, although I have heard a member speak highly of the conventional Rotella.

I'd maybe suggest the white bottles of Rotella that they've got at all the Walmarts.

Shell Rotella T 15W40 Motor Oil, 1 Gal: Automotive : Walmart.com

Cheap, good and I believe it is non synthetic. I've used this when they were out of Rotella T blue bottle and I was in a jam. Worked great.

What do you guys think of Rotella Tripple T in 10w-30? I believe this is conventional?
Shell Rotella® Products | Shell Rotella

I think that's the same one I suggested.

Tell him that Mobil One isn't a true synthetic anyway. Seriously, what mechanic is still afraid of synthetic oil?

Nobody runs 5w-30?

^^^ Sometimes I do in the winter.

OP, the Rotella is a good conventional oil. The shop where I work uses Rotella T as a break-in oil, and I'm using it right now in my ~200whp daily-driven Miata.

I'm trying to remember any oil that didn't look black after a short drive...other than that, can you describe why it "looked like crap"?

troll thread?

NO TROLLING... This is legit. I am not an oil expert so I will state that like the oil looked like it had 2000 miles of use as opposed to 800ish miles of use. Premature degradation is what I would call it...

I use Castrol GTX or the cheapass Rotella in my MX6. No complaints.

Degrading, or just getting dirty?

Big difference. Perhaps you have a garbage filter on it, or a garbage air intake system? Live on a dirt road, or in the desert?

No matter what oil it is, it just doesn't get dirty in a system in 800 miles. I just changed mine on my car the other day after 6000 miles (synthetic) and i could still see through it as it poured out.

And FWIW i use Valvoline in all my cars. 300k mile truck still gets the non synthetic Valvoline with a fram filter to this day.

To further answer your question, I think Valvoline VR1 is the only thing you can easily get off the shelf that doesn't suck and is conventional. Brad Penn is the jammy jam, but you have to either order it, or have a local speed shop that carries it.

Let's ask a more fundamental question -- let's say that you use synthetic oil, and 400 miles down the road your engine blows up. How exactly is your mechanic going to verify that you were using conventional rather than synthetic oil?

I realize this would involve outright deception, but seriously, he's asking you to use a less protective oil.

If your oil is turning black very quickly after an oil change, you may have a broken piston ring that is allowing combustion byproducts to contaminate the oil.

I don't like the idea of using a conventional oil on a turbocharged engine. Mainly because of the turbocharger, not the engine. The oil will see MUCH higher temperatures in the turbocharger due to the exposure to exhaust heat. Synthetic oil handles this better (resists coking). If your turbo is the oil-cooled type (like mine), then the recommendation to use synthetic goes 2X.

Your mechanic sounds like a flake.

I agree with you Hornetball. I think his mechanic *is* a flake.

However, typically, aren't you supposed to stay out of boost for X miles post-rebuild? Hence wouldn't this theoretically help a great deal with turbo temperatures? /Theoretical question for my own benefit/understanding, not debate-intended.

it still sounds like troll thread. or troll mechanic. or mechanic who believes in old school dogma over real world science.

break the motor in for a few thousand miles on whatever oil you want. at that point the warranty becomes meaningless if it hasn't failed on its own.

then switch to synthetic so you aren't a frequenet repeat customer.

For break-in, conventional is the way to go (and if you can find non-detergent oil, even better). Coked turbo bearings is somthing that happens over the long-term, so don't sweat it during break-in.

I think OP stated that he was past the break-in stage though.