Mixing Oil

Hey, Guys,
Any idea if it will hurt to add a quart of 5w-20 to 4 qts of 5w-30 (Castrol) ??

 

its fine. you just can't mix synthetic with regular dino oil and vice versa. same type of oil but different weights is fine though.

 

You can mix synthetic and dino.

 

Care to explain why not? They make a synth blend right?

 

Like mixing water and oil. They simply don't mix. Synthetic and regular. There not the same also. 10/30 synthetic is based on 30 weight. regular 10/30 is based on 10 weight and has additives to thin it out.

Had a crank case of a compressor opened up once. Poured some synthetic in and it washed the previous oil out of the pipes and just floated on top. Needless to say drained it again and filled it again with synthetic.

Some blends you can indeed mix but you run the risk of foaming.

 

Oil is oil, whether synth or dino. 10w30 synth should be the same weight as 10w30 dino, otherwise they wouldn't have the same weight characteristics, right? Oil isn't supposed to foam unless it has absorbed moisture or has some other additives in it like that Lucas oil additive.

 

It's your truck mix away but really they don't mix. Try it yourself before you try in the engine.

You might want to read this page first though.

http://ferrarichat.com/forum/faq.php?faq=haas_articles

Operative word there up above:

That's not you mixing them. there is a huge difference. Unless you manufacture oil maybe avoid the chemistry.

 

You can mix the 5w20 with the 5w30 no prob. You're talking about conventional oil of the same brand, so go for it. If it makes you feel better, I have a 5qt jug of 10w30 from my previous vehicle, using it up by mixing 2qt 10w30 with 4qt 5w30, same brand conventional. So lately I've been running a "7w30" LOL. Can't tell any difference, starts fine and runs great. And just like before, the oil stays clean for about 1500 mi before starting to change color. No change in fuel economy either. Actually it might be helping a miniscule with the hot summer.

Not sure why they would thin out a 10 weight oil, maybe you meant to say thicken it up.

 

Maybe, wasn't paying attention it's was late.

 

I was told by my Ducati dealer never add a different brand of Syn. oil to my bike. In a pinch add dyno oil. ---- Do not mix Syn oils.

 

Motorcycle motor oil has friction modifiers for the clutch.

I haven't had problems mixing regular and synthetic motor oil; thats what synthetic blend oils are.

 

Friction modifiers in modern automotive oils can cause problems with motorcycle clutches.

Motorcycle oil rated JASO MA1 do not contain these friction modifiers and are generally more comparable to API grades SH to some SL grades. API SM grades can cause major problems, both with motorcycle clutches AND with automotive engines that use flat-tappet cam designs.


Nice necrobump of a 2 year old thread that contains much myth and misinformation.

 

Any oil thread anyplace is loaded with controversy...it's always been that way.

 

It wouldn't be controversial if people would ignore the myths that they've heard from old timers and the marketing campaigns of whoever and would actually do their own research and pay attention to those who have used scientific methods to show what's going on.

But the results of poor choices are long-term issues. Very few people are going to have an engine damaged by a Fram filter or inferior oil, because very few people keep their vehicles for 200k+

And my "myth and misinformation" comment was directed at Trap, not you, but Trap hasn't been on the forum for a year.