I have 1998.5 Cummins with 250,000k. My tranny only has about 40k. This problem persist with my truck often. It's the normal tranny lock amd lockup problem notortious with these trucks. I know this is a popular topic. But I can't find any threads on it...pertaining to the alternator.

I've tried about everything.
1. Disconnect battery cables.
2. New Battery cables.
3. Cleaned APPS Sensor
4. Checked and cleaned grounds
5. APPS reset by slowly pressing and releasing brake pedal.

I had my alternator tested this morning. It's only reading about 11.5 to 12 volts. I was told it had bad diodes and should be reading about 13.5 volts. My question is, could the alternator be causing this problem now???? In the past I've been able to disconnect the batterry cables for a while, clean the connections and everything would be fine for a few months. Now I can't get it to stop.

Any suggestions would greatly appreciated.

 

On my 2000, I had the same issue. I ended up wrapping the brown wire (orange tracer?) from the alternator with aluminum tape and putting on 2 ferrite chokes (1 at each end). It solved my problem. Actually what really solved my problem was trading the truck off at the dealer after I found out it had the cracked 53 block and was leaking antifreeze where it was cracked.

 

We have the solution for this issue, we call it the apps noise isolator part number 1300030. If you would like more information please contact us.

 

PROBLEM SOLVED !!! Replaced alternator today and no more locking and unlocking. Must have been bad diodes sending out stray electrical pulses causing the problem..