So I bought my truck last year. Didn't really notice but only a few times last summer, and a lot this summer. If I am cruising around 40 to 45, which seems like the average speed in town, my tranny keeps jumping from one gear to another! The shop that rebuilt the thing says its a bad ground. I've gone through and cleaned up everyone I could find and its still doing it.... any suggestions?

 

A noise filter (available from dtt) should solve your problem. Aside from that I would verify the apps sensor is within range and producing the correct voltages, possibly ground the apps (I think instructions with pictures are available on suncoast converters) , and as I do with every 24v truck that comes in, clean the battery terminals and clean existing or install external ground on the pcm.

 

Do you have a link for the noise filter?
Not to sure about the apps sensor?? Or grounding the pcm with an external ground.

 

Diesel Transmission Technology - DTT Performance Diesel Transmission and Power Accessories

 

OP,

I did a re-wire involving running a wire from the Apps to the Battery ground. This worked for me and solved my issue. You should be able to find it under a search for Suncoast Apps ground....I think. It is a pdf file that suncoast has. If you have some wire on hand then it will cost nothing but time to do it.

oudive

 

They used to have it on their website but don't anymore... I did it too except grounded to a clean area on the frame. Worked until my lock up solenoid went out.

 

disconnect the 2 ground wires and wait about 45 min. to 1 hour than reconnect terminals get in truck turn on ignition press down throttle all the way very SLOW than back up very SLOW turn ignition off than start up truck and and see what happens also wrap the alternator main wire out of the back of alternator tan and white I believe with aluminum foil sounds crazy but that did the trick for me 1500 miles so far no problems

 

sweet, I'll look into it. Thanks

 

I know this sounds a little crazy but the alternator puts out a lot of electrical interference and confuses the apps and again I didnt believe it would work but it did let me know what happens.

 

I had the same problem for 6 months I cleaned every ground under the truck and under the hood it would work for 2/3 weeks then it was back ....But then it came to me on the passanger side firewall the control box is there and it has a little ground wire to the firewall so I removed the one mounting screw and ran a new heavy gage ground from control box screw to firewall then to negative post on passanger side battery.. all fixed for 6 months now it shifts harder and I have no more sliping back and forth into OD. at 40/50mph.