speedomoter,odo, shifting problems

[ridiculously_necessary]

I just got done repairing a coolant leak. About 3 miles into the test drive my speedo pegs 90, odometer goes out. It now shifts hard into 2nd, and when going to reverse, it REALLY wants to go, I have to lay into the brake hardcore to slow and stop. Does this sound like the PSOM? (I bumped a thread but figured new was best) speedo is pegged even when off. all other guages work fine. I didnt get any coolant on any electronics, I dont think.

I also tends to idle a few rpms high when moving from drive to park, then takes a few seconds to idle down. could I have bumped a wire on the tranny?

[kylev90]

A speed sensor will make the tranny "confused" as to where its at. Not sure what the PSOM is lol sorry. My nuetral safety switch wasnt making good connection and my tranny did kind of what yours is doing but my speedo was fine.

[ridiculously_necessary]

PSOM = Programable Speedometer/Odometer Module. I picked that up in a search on this thread... *Intermittent* bouncing speeding and strange shifting

i hope its not that, what doesnt make sense if it is, is the shifting to 2nd and reverse problem...

edit: after reading the guys site, (in that thread) it does mention shifting issues... what does everyone think? anyone ever used arspeedometer.com?

[ridiculously_necessary]

ok, i spoke with Allen at arspeedometer. he hasnt seen this before but thinks its the VSS, and says that would cause shifting issues. and that hes never seen both the odo and the speedo go out together, so he things its a source problem, i.e. VSS.

so my next question, previous threads indicate there is no sensor on the tranny, but when i hit rockauto its shows several options, rear end, tranny, and ecu speed sensors. can anyone shed some light on this? meanwhile, this evening, i will be crawling under teh truck checkeing for corroded or grounded wires.

[superduty4x4]

The only speed sensor is in the diff. Ask for a RABS to get the right part, and don't be surprised if you replace the VSS and still have issues.