Mixing Synthetic & Dino Oil

[chef1366]

How bout this one.... Manuals say 10w40. I just filled with 15w40...why? Cos she seems to like it better. And its starting to get nice and warm around here. Supposed to hit 91 in the next day or so!!

And it ain't no dry heat!!!! \\/

[TheCafeKid]

And it ain't no dry heat!!!! \\/

Good lord no I wish it were. Makes me actually MISS Cali..and thats sayin somehting...lol

[Grandpa]

5W40 Rotella on the 129,500-mile GK. 800-mile trip, warm temps, a half pint used. Runs great.

This oil is what I use in cold and hot weather.

But the important thing is to keep level up. Topping off 5W40 Rotella with dino 10W40 is perfectly fine. We don't leave the oil in there much longer than 2,000 miles anyway, whether dino or synthetic.

[rustybronco]

Grandpa, how is the shift quality at 2k miles?

[Grandpa]

Exactly the same. No difference at all. I just ride, worryfree. Too many worrywarts on this forum.

I seldom let it go beyond 2,000 miles; usually I change it between 1,500 and 2,000, a wide window, depending on when it's convenient for me to do so.

Again, no difference in shifting or anything else, whether 200 miles after the change, or 2,000.

[rustybronco]

The reason I asked is I have two gallons of it to test. I have used quaker state 10w40 and at about 8-900 miles the shift gets clunky, rotella "t" 15w40 goes 1900-2000 miles, amsoil 20w50 over 4k and still going strong.
I will change it tonight to rotella 5w40 which should be the best bang for the money imho.