Cummins Driver
THE Cummins Driver
- Joined
- May 16, 2007
- Messages
- 2,405
Yesterday while driving my truck I was pulling a load in overdrive with the lockup switch on. I was coming to a stoplight so I hit the O/D off button to force it into 3rd gear to help me slow down a little, but nothing happened. I've had the lockup switch for many years now and never had this issue. So just for the sake of trying things I flipped my lockup switch down, and instantly it went into 3rd gear. It continued to do this for the rest of the drive to my dads house, however, if I have the overdrive off and converter locked, and then hit the button again to allow overdrive, it changed right into overdrive with no issues at all. The problem is only downgearing with the T/C locked.
The transmission is working perfectly other than this. Shifts are firm and lockup is normal while not using the lockup switch.
However, once I unhooked from the trailer I played with it some more and noticed that a couple times while downgearing with the TC lockup switch not on, it still didnt want to downgear. However, when i hit the switch again to allow it to go back to overdrive (that it never came out of), it unlocked the coverter then locked back up (like it normally would if going from 3rd to 4th).
It sounds like the switch may be going bad to me. I thought it could be internal, but the thing is working perfectly other than this. I havent driven the truck today to see if its still acting the same or not. Any suggestions or ideas? Thanks
Eric
The transmission is working perfectly other than this. Shifts are firm and lockup is normal while not using the lockup switch.
However, once I unhooked from the trailer I played with it some more and noticed that a couple times while downgearing with the TC lockup switch not on, it still didnt want to downgear. However, when i hit the switch again to allow it to go back to overdrive (that it never came out of), it unlocked the coverter then locked back up (like it normally would if going from 3rd to 4th).
It sounds like the switch may be going bad to me. I thought it could be internal, but the thing is working perfectly other than this. I havent driven the truck today to see if its still acting the same or not. Any suggestions or ideas? Thanks
Eric