Safe to mix Mercon V and Lucas?

[rctech]

Pretty self explanatory. Autozone was clueless as usual - is it safe to mix mercon v with lucas additive in my m5od?

 

[Gotta_gofast]

Why do you feel you need to add lucas snake oils? I would drain the old stuff and replace with some amsoil atf to your trans. It made my old truck shift smooth even in cold weather. If you suspect an issue, draining the old fluid can provide useful clues as to the history of what has happened inside.

 

[rctech]

Why do you feel you need to add lucas snake oils? I would drain the old stuff and replace with some amsoil atf to your trans. It made my old truck shift smooth even in cold weather. If you suspect an issue, draining the old fluid can provide useful clues as to the history of what has happened inside.

Oh I know it has issues, the previous owner let it run low (has a leak at the input shaft) and the countershaft bearings howl any time I'm on the gas. I've known lucas to quiet down bearings in differentials before, so I figured it might quiet down the ones in the trans since I won't be able to replace/repair it for a while.

 

[Gotta_gofast]

Ouch, sounds like a hard life! I would still get that old fluid out of there.