engine oil mixed

[Jasone]

I just realized that my dealer added a quart of 10-30 to my 5-40. is this a big problem? Do I need to chagne my oil now? I just changed it 300 miles ago but I have a track day coming up and don't want any issues.

thanks,

-Jasone

 

[Martin]

It should be fine as long as you change your oil frequently. The only possible problem that I can think of is if the additive package is incompatible (unlikely these days) - but with just one quart and if you change the oil frequently, I doubt you'll have any problems. All in all, it's much worse to be a quart low than to put a quart of mismatched oil in the car.

 

[plumcrazy]

cheap insurance to change it out, especially with same filter but im pretty sure its fine. wait for tom to give the final answer though

 

[Dom426h]

no prob, people do it all the time(topping off with a qaurt of random oil)

I'll save Tom from retyping what he has already said twice:

http://forums.viperclub.org/general-viper-discussion/626184-calling-tom-oil-guru.html

Yes, as long as the new jug is the same API performance level. Mixing different chemistry at 50-50 should be avoided (adding a quart when low is OK.)

http://forums.viperclub.org/general-viper-discussion/624690-will-5w-30-hurt-my-engine.html

You can always switch brands; mineral to synthetic and reverse. Part of the oil development program is to test for general compatibility.

The only thing not to do is a 50%-50% mix of two oils, even same brand. A 5W-30 and a 10W-30 both from Mobil don't necessarily have the same additive package. The problem with mixing additive packages is that some additives only work at 100% effectiveness at 100% of the dose. They work at 40% effectiveness at 50% of the dose. You may have two oils, each contributing 50% additive, but resulting in only 80% of the performance.

And before anyone panics, when you change your oil the amount left behind is not enough to worry about. Don't go double flush your oil, a simple change is fine.

 

[Tom F&L GoR]

I guess there's nothing left for me to do but give a stamp of approval.

 

[lh4x4]

All modern oils and synthetic can be mixed with no problem.