I JUST purchased a 1998 Firebird Formula M6. I am told it has had Mobil 1 10W 30 since new (or at least since first change). Here is my question... My oil pressure is around 18-22 at idle when hot. Under full throttle it gets up to about 45-50 when hot. The car runs well and just makes the regular motor noises for a car with 128,000 miles. Is my Oil pressure OK? Should it be higher at idle? Should I run thicker or thineer oil than this?

 

The manual says as long its between 20 and 80 it should be fine. Just because there is more pressure doesn't mean more oil is flowing. However, 18-22 seems a little lower than normal. Mine is usually 50-55 at idle, 80 at WOT.

 

Next question is.... If it is low..what is my next step?

Could the gauge or sender just be bad?

 

18-22 is low. Mine stays around 40-50 at idle and 60 at WOT. It never gets close to 80. I'm not sure what the problem could be but I would get it checked out. Oil pressure is the life of the engine. This may be stupid but have you checked the oil level?

 

Mine at idle is 45ish and at WOT about 60.

 

The oil level ir exactly where it should be.....
What type /viscocity of Oil do you guys use?

 

I use Mobil 1 10w30 in my LT1, I see the exact same numbers you do.

I think it's the oil

 

Thanks.. Makes me feel better. Anyone else running Mobil ! 10-30?

 

I have a 5.3 99 GMC run 6 quarts of Valvoline 5W30 for the pressure I listed above.

 

I changed the OIl today for the German Castrol 0W30 and gained 8 to 10 PSI at idle and now get 60 when I am on it.
Happy day!!!!!

 

That's awesome.

 

I still have no clue what the viscosties mean, etc.

I just know that 10w30 is a good all year round oil

and that oil guy site confusing the hell outta me

 

One thing you might try is adding some Lucas Oil Stabilizer next time you change your oil. I tried some and it added about 10psi at idle and WOT. Plus they claim it adds for better viscosity. I have never heard anything negative about the product either.

 

i have Mobil 1 5W30 with a K&N oil filter, psi is usually about 40 and just under 80 at WOT, and since changing to K&N psi jumps up fast when i hit the gas

 

No, not after I started getting my oil analyised (I did three on the Mobil - every one returned unacceptable results).

I'm using German Castrol Syntec 0W30 now.

 

I hear people on this site and others talk about Fram like they suck. I figure you guys know what your talking about I just wondered why. We use Fram on all our vechiles and they all have high mileage and no problems so far. Just wondered what sucked about them.

 

You mentioned Lucas Oil Stabilizer - is it safe in synthetic motor oils? I'm using RP in my '02 Z28. Might it improve conditions?

Gracias for any help/inpit/opinions.

Steve

 

yeh mines 20-30 idle..and 60-80 at wot..

 

Ditto ours is about the same except right after I change the oil... I use Mobile 1 SuperSyn 10W30...

40-50 at idle and about 60 at WOT

 

So where are you guys getting this german castrol 0w30? I've seen a picture posted of the bottle, it's black right? How do you tell the difference between the german and regular stuff? Also, I'd have to assume anyone who carries k&n air filters also carries the oil filters? What's the cheapest/best place to get these?

I too am noticing low oil pressure (~35 psi warm idle)using mobile 1 5w30 and want to try the castrol since everyone seems to think so highly of it. Also, do you guys run the 0w30 year round, or use a different viscosity when it's hot in the summer?