Tranny Fluid

[hdlogistics]

How often should you change the tranny fluid and filter on an AOD? I have a '91 GM and I'm looking to make my first change.

[Grand Marquis GT]

61K miles, its about due.

I usually do it every 30K, but I may be wrong..

[Ifixyawata]

If you wait too long (past 85-100k) then it may be too late. It was too late for my '84 Cougar with only 65k when I changed it.

[Grand Marquis GT]

but perhaps u should show how abused ur cougar was at 65K....

[Ifixyawata]

For reference, here are the heads on my GM... 209k miles:



Here, on the other hand, are the heads off of my '84 cougar. It had 70k miles or so when it died. In one day I lost 1st gear and the timing chain jumped a tooth:



See, changing fluids IS important!

[Grand Marquis GT]

Holy fuck!

[hdlogistics]

Well after seeing that, I'll be doing a change on the weekend.

[hdlogistics]

Just changed my tranny fluid & found the plastic plug in the pan. I guess that means that the fluid had never been changed since '91. The fluid looked a little dark but was shifting ok. Thought I'd better change it just in case. Seems to shift a bit smoother now. :jumpin:

[Lincolnmania]

i change my transmission fluid every 25.000 miles or two years, whichever comes first.........i use the same routine for cooling system service too
scott