PCMO questions

[Zero]

Is it acceptable to run 5W-30 oil in an older vehicle that specs 10W-30?

Will it harm anything if I run 10w-40 or 20W-50 in an older 5.7L engine that specs 10W-30? I've noticed the oil pressure light flickering on and off with the lighter oils, but the heavier grade oils will keep it from doing this. I know, I'm fighting symtoms and not the cause, but I just don't have the money to repair/overhaul the engine on this old truck.

 

[gregk24]

If your oil pressure light is flickering with the thinner oils then dont use them. As long as the light is off with the 10w30 that it specs for, just use that.

 

[rcbc96]

If you don't have consumption or leaks using a 5w30 is ok. Don't go thicker unless you need to

 

[dparm]

Yes, you can probably run the 5w30. Maybe try a high-mileage 5w30, which will be a bit on the thicker side.

 

[bullwinkle]

I ran everything from 5W30 Peak to 20W50 Castrol GTX in my worn out (cam bearings) 5.7 TBI, it burned them all! MaxLife did burn more slowly, though.

 

[MrMeeks]

RESTORE oil additive stopped my car's oil burning problem.

 

[Clevy]

Originally Posted By: MrMeeks
RESTORE oil additive stopped my car's oil burning problem.


And plugged your oil filter whether you were aware of it or not. It also didn't last more than a couple thousand miles.
That stuff has no business in an engine unless the motor is finished and your just trying to nurse it along until another vehicle can be obtained.

 

[CATERHAM]

Originally Posted By: Clevy
Originally Posted By: MrMeeks
RESTORE oil additive stopped my car's oil burning problem.


And plugged your oil filter whether you were aware of it or not. It also didn't last more than a couple thousand miles.
That stuff has no business in an engine unless the motor is finished and your just trying to nurse it along until another vehicle can be obtained.

I tried that stuff once years ago in an old oil burner I had with low compression and it does work noticeably increasing compression and "RESTORE" engine power for a while. But as Clevy pointed out it WILL clog your oil filter so that must be replaced and the effect only lasts for a few 1,000 miles.