TTAC Commentator Dave M writes:
A question for you and B/B. Especially during cold weather my Trooper gets a ’clunk’ shifting from 1-2 (it’s a 4 speed automatic) and then back down. This coincides with a CEL. It doesn’t happen all the time. There are other times (even during cold) where the truck runs normally – no clunk, no CEL. Checking the CEL code and it indicates all four oxygen sensors (replaced last year); when no CEL no code to read.
My first thoughts were it might be time for ANOTHER transmission. But my brother says no, it has to be electrical since it’s intermittent. Any ideas where to start?
Welllllllll…for starters you could write us with more info: stuff like the year/mileage/service history/CEL code totally wouldn’t hurt.
Perhaps it is time for “another” transmission, if we knew why you said it like that. Like maybe knowing the condition (look and smell) and age of the transmission fluid. Or perhaps the CEL isn’t fixed because Oxygen Sensors aren’t usually the problem: they are the messenger of a problem upstream. Maybe $10 in new vacuum line fixes the CEL, eliminate a leak that’s messing up both the engine and transmission’s parameters.
Or maybe you need a whole new transmission.
It’s kinda impossible to tell.
Come on son, us armchair analysts can’t judge a problem this complex with such half-baked info! That said, have at it, Best and Brightest.
Send your queries to sajeev@thetruthaboutcars.