schmoozer

Hey everyone,

My tranny fluid is still somewhat red but the edges when put to a piece of paper are dark which may indicate its time for a tranny fluid drain and fill. Its a 97 es300 so the manual calls for DEXIII, but I prefer not to put in the SuperTech Wal Mart brand or anything that;s not "brand name". I have an unopened extra quart of Mobil 1 ATF that's a few months old sitting around from when I did my power steering change, so I was considering using that, but part of me also wants to stick with OEM spec.

I made a few threads about this in the past and was leaning towards Amsoil, but at this point I think I want to just go and pick it up from the store and Mobil 1 and T-IV seem to be the only good candidates.

My question is, is that if I do say 3 drain and fills over the course of a few months is it safe to have Mobil 1 mixed with old tranny fluid. And on the same note is T-IV backwards compatible and safe with the old DEXIII fluid.

The goal is safety from failure haha.

Thanks for your help!

Lexmex

Yes, you can mix the Mobil 1 ATF with your old tranny fluid. I had to do the same thing when I changed from Type IV to Amsoil. I recently changed from Amsoil to Redline D4 in part because I want a change but also I've been studying viscosity differences and oil analyses and my two finalists were the Redline D4 or Royal Purple's Max ATF. The Mobil 1 is somewhat close in spec to the Type IV (they're actually both Exxon Mobil products), but with my RX300 having a modified tranny and torque converter (that runs a bit hotter) I need a bit better protection.

Lexmex

This is a little chart I made of Type IV compatible ATFs. The Mobil 3309 is Type IV fluid.