Mixing oils (engine/diff/gearbox)

[Smitters]

If using a Pela-style suction pump to change oil in a hard to reach diff or gearbox, is it OK to do one and then the other with the same pump? Obviously I'd let as much excess drain back into the first oil bottle before moving to the second, but naturally there will be some residue from, e.g. the gearbox oil when I come to do the LSD. Totally fine, or guaranteed disaster...?

Cheers for the advice. I have an innate ability to bugger things up, so it pays for me to ask first!

[chazola]

Well I've done this, and my car hasn't exploded yet As long as you're sucking up I wouldn't worry about it, I just make sure the very end of the pipe is clean first before using it on stuff like ATF.