Tach & overdrive light problems

[jim_doggett]

I have a 1993 F-250 XLT Supercab long bed diesel with auto, it has 145500 miles and the tach at idle is at zero but as you rev up the motor the tach works just fine and then from time to time when the tach is at zero the overdrive light on shift lever blinks on and off and other time it does the same thing when the tach is working. Can anyone tell me what I need to do to fix this

Thanks

[mak_272002]

The overdrive light flashing means a trouble code for the trans, you might want to find out what the code is, could be serious trans problem or simple if you take care of it now.

[rjpenny]

The 92 diesel has the same proublems, I am willing to bet that sometime soon its going to start stalling whenyou release the gas suddenly, turn up the idle a little. First thing to check with the trans. is the fluid level, then the seal at the back of it, after that you had better take it to a mechanic if you can't find the problem.

[KIKO_FIEBRE]

Hi,There.
Got same problems!!!
Possible solutions.
1- Tach sensor ( located on top front eng.)
2-Speed sensor (located on tail housing of trans / or in rear end.
Good Luck !!!

[jim_doggett]

Thanks for the info, I sold the truck and got a 2005 four door dully 6.0 diesel