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Cat 735 rock truck issue loosing all gears

Kels306 ยท 2025-04-14 08:38

I've got a cat truck serial number CAT00735TB1N01044 it's a 2008 , has a reman transmission in it , when brought back out to site the operator can drive it for a few hours then once put into neutral it will loose all gears , once it sits for a while it will go and work for a few more. Hours ,it will just read neutral for all gears with the selector

Replies6
  1. #1Mobiltech2025-04-14 09:08

    Have you got ET on it. If the dash reads neutral sounds like electrical issue either shift control or ecm.

  2. #2Kels3062025-04-14 09:45

    700 fm1 2 , the transmission sensor , thatll be under the cover on top of the tranny I believe, the only plug on it is on the side of it

  3. #3Nige2025-04-14 12:06

    Troubleshooting procedure attached. See where that gets you.

  4. #4Kels3062025-04-14 14:13

    That sensor is located inside the transmission cover ?

  5. #5Nige2025-04-14 14:41

    It's actually a rotary position switch rather than a sensor, even though the procedure says it's a sensor. Ref #20, mounted on the transmission control valve. They used to give trouble on rigid frame trucks, I'm sure they are no different on an ADT. If you want a full electrical schematic for the machine just ask.

  6. #6Rehtaeh282025-04-22 02:22

    Last week's hitch, my Two Bits while under a shovel, neutral,and park brake set. Began traveling in reverse when I have set her in first gear, released the service brake, and pressed the fuel pedal. The first time this happened I thought okay, what's going on. Stopped, reset park brake and neutral. Had to hear the shovel operator holler at me as though I did this on purpose. Placed the truck in gear again, released the brake, and she did it again. I quickly called in this issue to maintenance and dispatch. I was told this happens with low rpms? My load was 280tons, I wouldn't start off in any other gear, wouldn't that cause a stall? I'm so frustrated.