Chrysler Repair: 91 dodge spirit 3.o L v6 trans shifting, dodge spirit, hydraulic problem

Question
transmission will shift when cold but after a mile or two it stays in the lower gear and will not shift. I am thinking about a used trans. need some advice in what to do

Answer
Hi Ivan,
The trans is going into "limp-in mode" which is done to protect it from unnecessary damage when the controller detects a malfunction. I would begin by getting a dealer or a competent independent trans shop to do a readout for fault codes stored in the memory of the trans controller. They need an appropriate OBD-I type reader and a plug that mates with the "bus diagnostic connector" that is under the dash on the left-hand end. Find out the code numbers, what they mean, what they would recommend doing and how much it would cost. Then we can compare that to what the Chrysler trans manual says about those codes. I would not get a used trans as it is probably not going to be free of fault codes either if it is from a wrecking yard. I would figure out what is wrong with your trans first. It could be an electrical or hydraulic problem that won't require removing and rebuilding the trans. But only a code readout will tell you. I would not go to a nationwide franchise shop because they are focussed on putting in rebuilds.
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Roland