Transmission fluid again...

[JCL]

Originally Posted by sfcl

Reading and re-reading all the threads on the subject everywhere in several forums, choice is still not easy!
Roughly 3 options:
1- Drain the old fluid, replace the filter and the solenoid, and put again the old fluid in the tranny. Should avoid to move the old sediments which could cause new problems BUT the fluid is still old...
2- Drain the old fluid, change the filter, put in new Dexron III, VI or full synth fluid, so about 50 or 60% of the old fluid is changed, a part of it staying in the converter. Could cause new problems (limited as there is only a few new fluid) but could also extend the life of the transmission if it is not too dirty inside. A sort of compromise...
3- Drain the fluid several times (say 3 or 4 times every 50 miles or so), so get about 90% of new fluid. Major risk to let the new fluid dislodge old crap and cause new problems, but could be also the best option if the tranny is not too dirty by having a whole best quality new fluid in it...
Don't want to open a new poll on that but would be interested to know your thoughts! Curious too to know what a automatic transmission real specialist (no one around here) thinks of that...

If the fluid is that old, I wouldn't reuse it but rather put new fluid in. I wouldn't worry about Dexron VI, I would try and get a fluid that was current when the vehicle was built (given your lack of alternatives in your location). Definitely replace the filter. It isn't new fluid that causes problems as much as the process of changing it, and you don't have a choice there, once you have dropped the pan and drained it. Get as much out as you can, refill it, and see how it works. If you want to, do a second change in two weeks. You have a real possibility of this solenoid not curing the problem, so go a step at a time and see how it responds before spending too much money on it. Just my $0.02.