QuestionQUESTION: A computer reading shows "underdrive" out of range. If I turn off ignigtion is drives fine. Tends to go into Safe mode when car gets hot and am driving in traffic. Speed sensors were changed but did not help. Only does this once in awhile but transmission is now slipping. What can/should I do?
ANSWER: Hi Frank,
I don't see exactly that code name. Do you have the code number or the exact wording of the code? That would help in determining whether the rebuild is necessary or perhaps a valve body repair. Have you checked the fluid level? Have you checked for obstriction to air getting through the radiator/transcooler fins due to leaves/debris? You might also consider a drain/refill with ATF+4 fluid. But a specific code number as above would be helpful to me.
Roland
---------- FOLLOW-UP ----------
QUESTION: I don't remember the code. It was a hand held device and it showed an underdrive range up to 70 but my car went to 73 (overrange) and went into safe mode. When I do stop and go driving I do smell a burning smell. I was told it could be a problem to drain and refill the the fluid. Car has 120,000 miles on it and since retired don't want to spend alot on repair. The slipping just started. Can I safely add fluid which is supposed to stop slipping? Any help is appreciated. Thanks.
ANSWER: Hi Frank,
I can't give you assurance that adding a slippage improving fluid will help, and it could do harm. If the transmission fluid itself smells burned then that would be a reason to do a complete flush of all 10 quarts using a power flush machine. That would only be a very outside chance of correcting the problem, but if you are going to do it I would do it now.
About the only other possibility is a valve body/solenoid pack repair, but that would be accessed as to its efficacy only if you could get the two-digit fault code. There is a blue plug under the dash by the fuse box into which a code reader can be plugged and a competent garage with an OBD-1 reader and a Chrysler Data Link connector that matches that plug and which can read the trans fault codes is probably the most useful information to get on which way to go.
Unfortunately, the teardown/rebuild of these transmissions is costly and I suspect that at 120,000 miles this is what needs to be done to repair this situation. Maybe spending your effort on comparison pricing/warranty backing for such a rebuild is your best choice.
Roland
---------- FOLLOW-UP ----------
QUESTION: I stopped in at another shop and they got computer readings of codes 32 and 56. He suggested we start with a fluid change. Says if he drops the pan should be able to make a decision, because he can see what residue is in the pan. What do you think? Thanks Frank
AnswerHi Frank,
The 56 suggests there is a problem with the turbine speed sensor or its two wires which are connected to pins 13 and 52 of the trans controller plug. That sensor is the one on the driver side of the trans, close to the front of the trans. It costs between $25-80 depending upon where you buy it, and it is easy to replace (lift tab on plug gently to remove, unscrew and screw new one in, tighten to 20 ft-lbs about the same as a spark plug).
The 32 code says there is a problem with the 2/4 hydraulic pressure switch which could be do to a leak problem in the solenoid pack which can be replaced, or with a leak in that valve in the valve body which can be repaired by dropping the pan/removing the valve body and repairing the valve.
I agree with the idea of dropping the pan and observing for debris which would indicated clutch slippage or other damage that would call for a removal and rebuild. If it was OK, then flushing out the old fluid and putting in all new ATF +4 would be a good remediation.
But, you might begin with checking the two wires to the turbine sensor and replacing the sensor if those are OK. Then try the solenoid pack replacement which is an external job. Then move to the pan drop and evaluation/oil flush as the third step. But I would discuss this some more with the last shop and then decide which order to take. You will want to change the oil in any case, so maybe that pan drop would be a good idea to eliminate the possibility that the trans is so bad as to require a rebuild, in which case all the other things are moot.
Roland
