Engine Oil mixing?

My teg is a little low on oil, and i wanna fill her up, but i don’t know what name of oil the lube shop used my last oil change. Would it matter if i used different brand names of 5w30? Or should i try and stick with the same one?
Thx

you could always call them and ask.

it dont matter. you’re not going to hurt nothing. if you’re low on oil, jus go ahead and top it off with another brand but the same oil weight. for future reference, try to stick to the same oil brand when possible.

u should always make sure what they use. well u can just do a oil change again.

Re: Engine Oil mixing?

Originally posted by 91TEG_GS
My teg is a little low on oil, and i wanna fill her up, but i don’t know what name of oil the lube shop used my last oil change. Would it matter if i used different brand names of 5w30? Or should i try and stick with the same one?
Thx

It is quite safe, but highly NOT recommended. Different brand oils have different additive packages and therefore could alter the way the oil behaves during “boundary lubrication.”

Boundary Lubrication is when the two mating surfaces are applying extreme pressure against the oil…which is literally squeezing it out. It is up to the oil’s additive package to keep the oil in between these two mating surfaces, or at least provide the lubrication. Without this, there would be metal-to-metal contact, which something the oil is suppose to prevent.

Now, after saying that, it is OK to switch oil brands and/or oil weights. This is provided that you do a complete oil change using (insert oil brand here).

As for mixing oil weights. That too is possible and safe, as long as you stay within the SAME oil brand AND line-up. For example: If you are currently using Castrol GTX 5W30 and want to mix in a 10W40 to create 7.5W35, it’s best to stick with Castrol GTX 10W40 rather than going with Castrol Syntec 10W40 (Syntec doesn’t create this type of weight, I’m just proving a point). This is because all GTX line-ups have pretty much the same additive package and the same type of basestock oil. The only major difference are the viscosity weights.

I hope this explains to you why it is not recommended to mix oils.

Regards,

Oz

Mixing oil weights is not safe. If you’re in a pinch, it is better to mix weights then to drive with a low oil level, but you shouldn’t leave it that way for long.

Originally posted by gobows
Mixing oil weights is not safe. If you’re in a pinch, it is better to mix weights then to drive with a low oil level, but you shouldn’t leave it that way for long.

How come?

Oz