is it OK to mix engine oils?

[sixdogs]

I use sythetic 0W40 in most of my things and because of that don't have a lot of dino oil around. I need an oil change in a newer Kubota that I don't want to switch to synthetic yet and have a gallon of left over Deere 15w40 and could add a gallon of Delvac 15w40 I have in the basement. It saves me from buying more oil. I cant't imagine a problem and wonder what others think?

 

[kensnelling]

Personally, just do it. All oil additives are the same (just some brands use different propations) so it's not like you'll be creating an acid compound in the crankcase.

Ken

 

[LD1]

Last I had heard about oils, is that its okay to mix dino oils as the SAE (or whatever governing body) requires them to be compatible. But that isnt always the case with synthetic oils.

 

[Bird]

Supposedly, 50+ years ago, different brands had different additives or detergents, so I was taught as a teenager to not mix brands. Now I understand that's not the case anymore; they should be compatible. However, old habits are hard to break; I still would not mix brands.:laughing:

 

[kuboman]

John deere explicitly warns against mixing oils. I would not. How many hours on the Kubota. If your past breakin then put in your synthetic.

 

[sixdogs]

John deere explicitly warns against mixing oils. I would not. How many hours on the Kubota. If your past breakin then put in your synthetic.

Not past break in and only 60 hours. Figure 40 more on dino and switch to synthetic.
This dino oil I have is just leftover stuff I'd live to use and get rid of.

 

[PHILIP8N]

How much is your tractor worth? How much is the oil? Will it effect your sleep at night? FWIW, I changed to 5w-40 full synthetic at 50 hours. Philip.

 

[Gary Fowler]

Some manufacturers specifically state a time limit where it is not recommended to use synthetic oils. I would follow that advice however, I wouldnt have any qualms mixing different brands of DINO oil of the same SAE weight specification. They are all compatible in the DINO oil, however Synthetics may not be, so I would stick with the brand that you decide to use and not mix them even when changing oil. Decide what brand you want to use and stay with it as there is a possibilty of some oil being left in the engine when changing. Might not be an issue even with Synthetics but some folks here claim to be knowledgeable of it and say that some synthetics are not compatible with other brands. This might be a myth propagated by the oil companies to keep you using their brand buy why take the chance.

 

[Tig]

I was taught as a teenager to not mix brands.

Cue the steam engine jokes.
FWIW, I was taught to not mix also, so I don't in the machines I like.

 

[LD1]

Cue the steam engine jokes.
FWIW, I was taught to not mix also, so I don't in the machines I like.

What about the machines you dont like?:laughing: