Adding Oil - Can't mix brands??

Where did you get the idea you can't mix brands ? It all originally comes from the same stuff out of the ground you know ! ;-)

Graham

Mixing brands isn't the very pinnacle of practice. Mostly, because the additive systems used in the oils may be different and, when mixed together, may not function quite as well as either manufacturer had intended. But I don't think serious problems will occur when you add in a different brand between full oil changes. It's more important to maintain a proper oil level, I think, than any variance in performance from adding in a different brand.

Jon

If you never allow someone to put Pennzoil or Quaker State in your car, it will never be an issue. http://66.102.7.104/search?q=cache:ZLms9LDGUqoJ:

"Still" true? It was never true to begin with. Sounds like something that your grandfathers grandfather passed along.

Yeah, the stuff that says "Motor Oil" on the label. Follow your owners manual recommendation on viscosity and you'll be fine.

That oil pressure reading is from but one spot in the oil system, it in no way means that there is adequate pressure under these circumstances anywhere or every where else in the system, that is why your engine has both a dip stick and a pressure gauge. Your logic has you cutting off the arm to save the hand. Just put some oil in it.

Rich,

It's usually okay if you don't mix Tyrannosaurus-based motor oil with any from the Brachiosaurus. Read the label very carefully, and make sure that the motor oil your using is at least Dinosaur-based, i.e., not prehistoric foliage- based. Ask the person selling it if you need to.

--Mike

Many years ago, when multi-viscoscity oil was the new latest thing in oil, there was some truth to what you said. At that time, the oil additive packages of each oil may not necessarily be compatible, and the mixture of two (oils) viscosity modifying packages would combine chemically to make a thick sludge.

But that ended probably in the (early) 1950's, as improvements in oil additive packages happened because of that problem.

It has not been a concern for a long, long time. However, don't try mixing a synthetic with a motor oil, necessarily. But motor oil to motor oil is fine.

It's a Grandpa's story. True at one time, but not now.

Best-- Ron Registered Certified Fluid Power Engineer (finally retired)

In particular - low oil level wil cause problems with hydraulic lifters.

Graham

throw some Castrol GTX 10-40W in it. kind of sounds like your engine either leaks it or burns it.

re : mixing motor oils...

Here's my version. It wasn't very long ago that any high multiviscosity oils created sludge with heat like 10W-40. Thats why 10w-30 was standard with diesel or most any engines under strain. I read that in CR at least 15 years ago. Sometime after that, things changed, to where they started recommending the things other than 10W-30. For the most part, all oils must be made to combine, even synthetic. greg

I got that idea from some guy at the oil store sometime last millennium: "It's OK to mix weights, but not mix brands." Supposedly, something to do with the particular additives.

Thanks! Rich

Thanks for this. :-)

Cheers! Rich

Yes - this is why it had started going "ticka-ticka" when I started it.

I want to thank you all for your answers - Being the impatient guy that I am, I went ahead and took the chance, bought two quarts of the least expensive oil I could find, poured it in, and the car seems happy now. :-)

I have REAL GOOD oil pressure now. :-) :-) :-)

I also watered the battery a little - but that's a topic for another post.

Thanks! Rich

...

Yeah, I'm pretty sure "leaks it" is closer to the truth - there are spots where I park it. And, of course, I was raised to believe that car motors always consume some amount of oil, as if it's just a normal thing to do. And from the little I know about internal explosion engines, it seems logical. When I was in the US Air Force, I used to watch the ground crew servicing an EB-47 (yeah, very few people have heard of them - very weird airplane) and the first thing they did was pour about six quarts into each engine. But that's supposedly not a design flaw. At the airplane factory, they probably called it a "feature". ;-)

Thanks! Rich

Did you mix brands?

I recommend Sparkletts ;)

Bob

I read in sci.electronics.design that "Rich, Under the Affluence" wrote (in ) about 'Adding Oil - Can't mix brands??', on Mon, 10 Oct 2005:

HEAVY!!

Gah. Put more oil in.

Whoever told you not to mix brands was also probably telling you how you're supposed to change the air in your tires every 3 months, right? :-).

Ask them for that and they'll laugh their asses off! (And probably give you the same answer they give to those who want to change the air in their tires...)

Tim.

BS! I've always buy whatever brand name oil is on sale. I change my oil on a regular basis, every 3k miles, with no ill effects. Just make sure you get the proper viscosity oil.

-------------- Alex