MTX Fluid change - Did I screw up?

[Mark in PDX]

I had a free service coming at the local Oil Can Henrys and they offered to do my MTX... Since the car has 175k miles on it and I am not sure it has ever been changed, I let them suck it out and replace it.
I wasn't really thinking about it when they did it, I was busy with my kids who were bugging me... When I looked though, they put in Castrol ATF, a Dexcron based ATF.
I drove the car quite a bit yesterday afterwards adn noticed it seemed to be shifting a little smoother, so didn't worry about it. But then I was on here and for a lark looked up what was recommended for my 89 5sp... You guys like Redline or the GM Synchmess.. This tranny hasn't been rebuilt since I got the car at 80k miles.
So I assume I have the brass locking rings.
Will I start to have problems, or should it be fine? We haven't gone over 3rd gear as all the driving was in residential neighborhoods after the changes.
Please advise...
Mark

 

[shojuan]

There's nothing wrong with the Castrol ATF. It meets the specs of what needs to be in there. The most important thing is does it shift smoothly? If it shifts smoothly now it will likely stay that way for a while. A very knowledgable person on this forum, Mark Nunnaly, suggests changing out conventional ATF fluid every 10,000 miles or so for maximum shifting performance. Not a requirement though.

 

[SHO--ripper]

If it shifts fine then there is no problem. Next time you change it try a different fluid and see which gives the best results.

 

[Blast7]

I changed mine once and replaced it with Mobil 1 ATF and I couldn't really tell a difference. I got about 1 quart of the old stuff out. The only thing I did notice was more of a leak through my axle seals. frown

 

[sdpatt]

I have the Castrol ATF in my MTX also. It works just fine. You can add a few ounces of Ford Friction Modifier to the case to smooth up the shifting even more, but it is not required. Acoording to Ford, neither are fluid changes with the MTX. There was no recommended change interval in my owners manual.

I have replaced the fluid in my transaxle several times, but I believe that the key aspect of transaxle longevity is the cleanliness of teh internals. Unless there are contaminants introduced through the fill plug or there has been a catastrophic seal failure, the internals should be immaculate. Even after all the miles on my transaxle, the internals were extremely clean.

<small>[ April 28, 2003, 08:20 AM: Message edited by: sdpatt ]</small>