Can I safely mix oils?

[Vince_R]

So the situation is this. I have a old van that i am going to be trading in next year. And it is now time for a oil change. I often go to autoparts stores like autozone and get there oil change deal. A filter and 5 quarts of dino for x amount of money. My van hold 4 and a half quarts. So i have plenty of half full bottles of oil laying around and want to use them on my next oil change. I have a Quart of QS 5w30 green bottle, a Quart of Pennzoil 5w30, a Quart of QS extended performance (dino) 5w30 and a quart of Valvoline 10w30.

So this is my question. I know that the QS and Pennzoil are Shell products and not that much different. And since there ther same Weight i don not expect any troubles. But what about finishing off 4 quarts of 5w30 with a half quart of 10w30. from another brand. I don't expect any trouble since there are blend oils out there. But just wanted to get a second opinion. Thanx

 

[barlowc]

Mix and use up what you have. You'll do no harm.

 

[addyguy]

Absolutely no problem - you can mix ANY engine oil with another one w/o issue.

 

[pompadour]

you will have no problems with that. clean out the garage with the car you are trading in.

 

[c3po]

Originally Posted By: pompadour
you will have no problems with that. clean out the garage with the car you are trading in.



Go For It.

 

[Bill in Utah]

Not a concern. Use all of what you have together with NO WORRIES!

Bill

 

[brentalan]

Just make sure you change your signature to:

1998 Chevrolet Astro 4.3L
2/5 Quaker State 5W30
1/5 Pennzoil 5W30
1/5 Quaker State EP 5W30
1/5 Valvoline 10W30

 

[sciphi]

You're fine.

 

[HK_Ace]

I have collected quite a few bottles German Castrol now. I also really like Pennzoil Ultra. I wonder I can mix those two and get the best of both worlds...or the worst of both...

 

[Jim 5]

I had a really good UOA on a witches brew just like this on my '98 Chev K1500 some years ago. You'll do no harm at all.

 

[mechtech2]

Sure - go mix and use your oils.
either for a new or old car.

But I must say, anytime someone came in the shop and said "Just fix it so I can sell it" or, " We are getting rid of the car, just do a quick fix it for right now.", meant that the car would be around for at least two years.
I have never seen this to fail , empirically.

 

[Papa Bear]

Be sure you are wearing safety glasses when you fire it up .....

 

[HK_Ace]

It should be fine- none of the chemicals react with each other. A German Castrol and Pennzoil Ultra brew may be the best oil yet.

 

[Lethal1ty17]

Originally Posted By: HK_Ace
It should be fine- none of the chemicals react with each other. A German Castrol and Pennzoil Ultra brew may be the best oil yet.

i've wanted to try in a 5qt sump
-1qt ultra
-1qt edge
-1qt m1 ep
-1qt amsoil
-1qt redline

just think of the possibilities

 

[Jim 5]

Originally Posted By: Lethal1ty17
Originally Posted By: HK_Ace
It should be fine- none of the chemicals react with each other. A German Castrol and Pennzoil Ultra brew may be the best oil yet.

i've wanted to try in a 5qt sump
-1qt ultra
-1qt edge
-1qt m1 ep
-1qt amsoil
-1qt redline

just think of the possibilities


You'll lower the wear by 50% if you put 2 oz. of GC in that mix.

 

[Faststang]

Take this for what it's worth but I have friends working in the mechanical engineering dept for a major automotive company and the latest news is prevent mixing oils at all cost. Apparantly additives from some oils react badly with additives from others.

 

[shrooms]

Originally Posted By: Faststang
Take this for what it's worth but I have friends working in the mechanical engineering dept for a major automotive company and the latest news is prevent mixing oils at all cost. Apparantly additives from some oils react badly with additives from others.


People have been mixing for years. I've yet to see a bunch of cars with destroyed engines lying on highways and streets.

 

[Faststang]

The reason I came to this forum is to find usefull information about oil and I'm sure everyone else on here is doing the same and for that reason.

I have yet to see a daily driven vehicle using supertech recycled oil die either, it doesn't mean it's the best solution, or a good idea to drive your expensive engine with it. I'm sure there are thousands of people doing it and I sure don't see cars on the side of the road because of it.

If you want to argue with manufacturer findings be my guest, go ahead and mix away, it's not my engine.

 

[SLCraig]

My car currently has in it:

QS durability syn.
Formula Shell 5 and 10w30 for topups.
Runs great, quiet as a mouse

 

[KrisZ]

Originally Posted By: Faststang
Take this for what it's worth but I have friends working in the mechanical engineering dept for a major automotive company and the latest news is prevent mixing oils at all cost. Apparantly additives from some oils react badly with additives from others.


Tell, how is this major automotive company goinng to acomplish that, when part of API and ISLAC specification is backward spec compatibility and ability to mix different API certified oils?