I hate to ask another oil question, but...

[Steven B.]

Re: I hate to ask another oil question, but...

That's why a lot of cars just have warning lights, nowadays. Last week I evaluated and test drove a MINI for a friend - no oil pressure gage, temp gage, or voltmeter - just warning lights and a ton of "comfort and convenience" bells and whistles. The "fuel gage" consisted of ten LEDs that progressively go out as fuel is consumed - different that what I am accustomed to, but equally functional.

GM trucks have a better gage suite than my '91 MR2. Back when the car was new I asked some Toyota marketing execs about this, and they told me about all the letters they got about too much to too little oil pressure when Toyotas had oil pressure gages. So they just eliminated the gage, and replaced it it a low pressure warning light on all models.

C-category oils are blended from the same base stocks as S-category but the blend of viscosities and VI improvers varies with the desired final SAE viscosity range.

If you look at owner's manuals from the sixties and seventies, many say straight SAE 30 is okay for cold starts down to 40 F, so I could use it year round in my climate, but the lower cold viscosity of a multi-vis blend does reduce oil flow resistance and probably cold oil pressure.

High cold oil pressure means the bypass circuit can't flow enough oil even when the valve is full open, but most engines will not exceed normal hot oil pressure once the oil reaches normal operating temperature which is something in the range of 180-230 F for normal road driving.

Of course the above assumes that the oil pump and relief spring are OE equivalent, which is often NOT THE CASE since every "engine builder" on the planet seems to want to install a high volume/high pressure oil pump regardless of what was OE, and this usually turns out to be the source of most "high oil pressure" problems.

Duke

I agree Duke. When I have rebuilt my small block street engines, normally adding about 100 dynoed HPand about the same torque, with head work, carb and ignition work, balance and blueprint, the stock pumps go on---oil and fuel. Overkill can kill.

Steve

[Michael W.]

Re: I hate to ask another oil question, but...

Unfortunately those gaugeless cars that are only equipped with "warning" lights won't give you much warning when there is a problem. By the time they read an out of range situation the horse has already left the barn. Maybe that's why they refered to them as idiot lights over the years.

The problem with gauges is with people not understanding what is normal and what is not- or spending too much time trying to interpret every little nuance instead of looking of out the windshield to see where they're going.

[Greg A.]

Re: I hate to ask another oil question, but...

Tom, the easiest way to get the 10W-30 product is to look in the yellow pages under "Lubricants" and find your nearest wholesale distributor (used to be called Oil Jobber). These businessmen (and women) purchase and distribute the full line of major oil products.

I work for Lubricants Div one of the major oil companies and can put you in touch with a distributor if you have trouble locating one...just PM me.

Greg.