I use penzoil 10W-30 (non-synthetic) in my LO3. I always put STP oil treatment in too. Is that helpin a bit or am I just wasting $2.00? Im probably going to Mobil 1 synthetic next change and i dont think i can use regular oil treatment with that can I? Also is there a big proctection difference between synthetic and part synthectic. and ive also been told once youve switched to synthectics you can go back to regular.
Thanks!

Brandon

 

save your money on the oil treatment, keeping your oil and filter changed regularly is far more important than what kind of oil you use. i use synthetic in some of my engines, regular pennzoil in others, and a blend a few others. never had any oil related problems out of any of them.

 

What he said. That STP stuff is thick which might raise your oil pressure, some, though I just use heavier synthetic to get the same effect.

 

my friend uses FRAM and Pennzoil.....supposiedly the worst **** you can do next to not changing them...he changes them every 2,000 miles(yes 2 not 3) and alot of his motors have over 200,000 miles and still going.. Yes...it is just changing the oil and filter regulary that is important......FAR FAR FAR more then using synthetic....i use Moble 1 tho....for the amount of mileage i put on the thing it does not cost me an arm and a leg and i know it will last a LONG LONG TIME. I don't want to put another motor in this thing untill i am 50

 

Enough on the petroleum vs. synthetic.


Back to STP: That stuff is a can full of an additive, called "viscosity index improver", or VI improver for short, typically put in multi-viscosity oils. It is a long chain polymer molecule that is used to help an oil that is low viscosity oil at low temperature stay thick at higher temps. Unfortunately, it is also the first thing to break down & oxidize under shear stress and high temperature.

No lubricant manufacturer would recommend an off-the-shelf additive to put with their product and still guarentee the performance. It's not just because they don't want you buying someone else's product, either. Why you would want to put it in your crankcase is beyond me.

 

Care to back it up. Just kiddin.

 

i agree with five7kid...if the oil makers had found that putting that stuff into an engine would help it theyd mix it with their oil. and look at the manufacturer's specifications for engines...none say to put in oil additives. another thing is to never use any oil additive that says it quiets the engine, improves horsepower, raises fuel economy, and also allows the engine to run without oil. it does all that, but at the expense of taking the anti-wear additives out from the oil...so if you tried that on a brand new engine it would not last that long. they have been reported to cause overhead cam engines to wear through cams in 40k miles...so i just stay away from any additive

 

This oil additive question came up once before when I was wrench'ing on planes.
The FAA does not approve (i.e. allow) use of additives in eng oil.
I believe Slick 50 was approved briefly, but was quickly banned after some guy put in too much and it plugged his oil screen,,, siezing his eng,, right after take-off.
Luckily, he made a quick 90 deg turn and landed on a taxiway.

I have run the real thick STP stuff when I limping by ol'67 Goat around, but it was burning oil so bad I had to install de-foulers on all the plugs. It did seem to help the oil burning rate a little. Instead of adding a qt every 50 miles, it was like every 60 miles..

If your eng is running good, stay away from all that junk.

I used to run Penzoil exclusively.
Never had a problem.
First time I torn down one of my Penzoil engs, I was shocked by how dull and dingy everything looked.

Switched to Valvoline after seeing how much cleaner the eng internals stay with it.