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Hot transmission

Help, my 1998 service van has developed a strange problem and only when the transmission get very hot. It bucks and surges, the check engine light flashes. I can relieve some of the surging by starting out in first gear or by turning the OD off. Is this a major trouble or an easy fix?

“my 1998 service van has developed a strange problem and only when the transmission get very hot”

Does your Dodge van have a transmission temperature gauge?
If it does, what temperature does it register?
If not, how do you know that the transmission is very hot?

Anyway–I believe that you have an engine problem, rather than a transmission problem.
If the Check Engine Light (CEL) is flashing, that is a signal that you need to take the truck to a mechanic right away, as the engine is misfiring. Continuing to drive it like this can destroy the very expensive catalytic converter and can cause other types of damage also.

A steadily-illuminated CEL means that you can pursue the problem when it is convenient for you, but when the CEL is flashing, you cannot delay the necessary repairs–unless you want to start adding big bucks to the potential repair bill.

My best guess is that this truck has not had the type of maintenance that it should have had, but ultimately you need to have a mechanic scan the OBD system for stored trouble codes in order to help lead him to the source(s) of the problem. Without knowing what trouble codes are stored, no mechanic can know where to begin to fix the problem, and certainly none of us can determine the codes from afar.

Hello, thanks for the quick response. More info should have been provided by me. It only happens when the truck has been driven a lot in stop and go traffic AND the outside temp is HOT( we live in Florida. ) The trans oil is clean and topped up, this is a fleet vehicle so it gets very frequent and good service. This problem ONLY happens when accelerating and does not show up when at a steady speed. I discovered today that turning the OD off only works briefly, the OD off light goes out when it bucks and surges. SO I started out in first gear( not sure if manual shifting of this trans is good ) and shifted through the gears with little of the surging. It appears to be in the OD operation, one guess is that the trans is trying to go into OD when it is still in 1st or 2nd gear. SO is there an easy way to isolate the OD by removing a fuse or a relay, or is this internal to the auto trans??? And no there is no temp guage on these vans…

READ THE CODES STORED IN THE COMPUTER TO FIND OUT WHY IT’S MISSING!! Forget playing with the transmission, that’s not the problem!

ALSO Betsy runs like a champ with NO troubles most of the time, ONLY when it gets HOT does she behave badly!

"this is a fleet vehicle so it gets very frequent and good service. "

Don’t you think your fleet manager should handle this?

Like Caddyman said, we need to know what trouble code/s is/are being stored. Get the computer scanned and post back with the code/s and we can help you further.

transman