Is it bad to mix different brands of ATF?

[wtd]

I have used Mobil, Quaker State, Supertech, and some store brand from O'reillys auto parts store in my 98 chevy truck with the 4L60E. All of it has been Dextron III.

The only name brand Dextron III around here anymore is Quaker State. The local K-mart quit carrying the regular Mobil Dextron III.

So should I stick with one brand, or does it matter?

Wayne

 

[Dick in Falls Church]

Wayne, there is a difference in brands. Personally, I wouldn't use anything but synthetic--
but apparently GM is concerned enough that they are putting out some new specs for a Dexron III upgrade. Think that was posted on one of the topics here the other day.

 

[wtd]

****,
I tried Mobil 1 synthetic ATF in the 4L60E in my truck and I experienced some slippage so I drained it out and went back to conventional.

Wayne