450C Crawler left Track suddenly lost power

[RightRudder]

I’ve read through quite a few other posts that kinda look similar to mine, but I’m throwing my symptoms out there for some help.

Serial # 450CC 376237T

Left track abruptly stopped getting power while I was down in a shallow hole I’d been digging around some tree roots. Right track still operates normally when I put the machine in gear, but left seems completely without power. No loud breakage noises accompanied track stoppage but I had double hearing protection on. Don’t hear any grinding from transmission or final drive when I put it in gear. Going to start pulling viewing panels in a few hours.

[Jim B]

Welcome to the Boards.

Your 450C has a wet clutch and brake steering system. The steering clutches disengage from driving when you pull the lever, actuating the valve to dump the oil from that steering clutch piston. Some possibilities of the cause, based on your description, would be failure of the steering valve, a leak in the hose inside the steering clutch compartment, or failure of the steering clutch piston seals. Those things would dump oil pressure, disengage that steering clutch, and the drive train would not make noise any more then when you pull a lever and steer it. There are more serious mechanical issues that could cause a no drive condition as well and might not make noise. I would check steering pressure first.

Do you have the John Deere Technical and Operator's Manuals for it?

[RightRudder]

Figured it out, all 9 sprocket bolts have slowly been coming loose over the past 14 months since we put new sprockets on. Hub seems to be undamaged, but track was down in a hole and there’s a rock guard over most of the sprocket so it was tough to assess visually. Use thread locker on those bolts, lesson learned.

[Jim B]

Thanks for following up with what you found. Clean the holes and use Loctite as you mentioned. It is a good idea to check them regularly to see that they are staying tight, for a while.