QuestionQUESTION: The tranny shifts pretty smooth up through the gears. But, feel a little jerk now and then at speed. When down shifting to a stop it kicks down hard. Would it be advisable to add Lucas tranny additive and would it help anything?
1996 Ford Windstar GL 3.8 v6 electronic OD transmission ~110,000
ANSWER: Hello,
There are a few possible causes for transmission harsh shifting and flare up.
If the fluid is dark or burnt, definitely change it and an additive shouldn't hurt.
Aslo, check for possible transmission or vehicle speed sensor codes.
If none of these help.. find a good transmission shop for advice.
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QUESTION: Thanks, the tranny fluid looks pretty good nor smells burnt. No tranny codes. Been getting engine code for the Air Idle Control(AIC) valve. It does idle rough on occasions and if gets worse was going to change it. Do you think the AIC valve could be affecting the hard downshift? Maybe I should try changing the AIC valve before doing anything else?
ANSWER: Hi,
The IAC valve is a common failure and they act up more as they get hot, but they should no affect the transmission in any way... sorry :(
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QUESTION: I appreciate your help and answer. The jerking seems to be worse when the tranny is really warmed up after diving awhile. Can you really check to see if the filter is bad or just change it? If I drop the pan and don't see any metal or anything else in the pan, change the filter and refill fluid and get same problem, does this probably point to the torque converter? Or if metal in the pan, likely the planetary gears? Thanks for the help.
AnswerA little bit of gray mud or sparkle in the pan is common.
I would always change the filter when the pan comes off, and you can peel the filter open to see if there are larger peices of metal.
If there are no codes, and a fresh fluid change and additive do not fix the problem, then you are most likely looking at a rebuild.
Honestly, even if filter change with additive cost you $200, it is worth it to try vs a rebuild on anelectronic Transmission with all updates (most likely) at $2500-3000
