JD 350B Loader Rough Vibration in Reverse Only

[D.Light]

Today while running the 350B Loader, I noticed a rough vibration or grinding noise ONLY while moving in the reverse direction. I fear it is a transmission problem, but I'm hopeful some of you guys have experienced this and have alternative suggestions. I guess it could be a final drive or a binding brake band... ?

I do have a reverser so the transmission is not being shifted from forward to reverse. I use the reverser to change directions.

Also - While moving in reverse, the right side track seemed to be grabbing a little and actually stopped and almost seemed to be locked up momentarily. Upon moving forward, everything is fine.

The foot brake also seems a little tight.

I'm not too familiar with the final gears, but I do know there is a gear and bearing that has an accessible cover. Could this gear and/or bearing cause these symptoms?

Any suggestions appreciated!!

David

[townlineterry]

The track locking up momentarily sounds very much like bearings going out of the final drive. If that is the case DO NOT drive it anymore that needed except maybe to get it to a place to work on it. If you see oil leaking around the pinion shaft it is probably 90% the bearings went.

Terry

[D.Light]

Is the Final Pinion Bearing a common problem and I assume it is repairable by removing the Pinion Bearing Housing Cap?

Would the Final Pinion make a louder noise in Reverse as opposed to Forward?

I really appreciate the feedback.

[townlineterry]

Not familiar with the 350, however replacing the bearings means removing the finals from the crawler to rebuild them.

couple of things to check before you do that. Jack up the crawler and pry up on the drive sprocket, there should be no movement, if there is then you have bearing problems. You can also remove the oil pan from the bottom of the finals, if you have metal shavings, or roller bearings, any kind of metal in the pan you need to get into the finals.

Terry

[D.Light]

Thanks Terry. I'll check it out.

[Scottyb]

David, I had a similar problem with my 350b two winters ago while moving snow. It got worse quickly and then would lock up completely when in reverse. Normal in forward. I could see and feel the brake pedal firm up when this happened. I loosened up the brake bands and drove it back to the yard. I re adjusted the steering clutch and brakes as per the manual, and adjusted the brake pedal linkages to balance the brakes evenly when the pedal is pressed and... it has worked perfectly ever since. I suspect in my case the problem was that the brakes were not evenly synchronized to the pedal and it was causing one band to grab in reverse. This would then pull or push on the pedal linkage and in effect cause the other brake to grab as well. Does your brake pedal return to the top easily after it is pressed? Mine was a bit stiff, I discovered this when I was doing the adjustments. It might have been staying slightly depressed at times and pulling on one brake in reverse.

Just happy it works now. Hopefully your problem will be as easy.

Secondly, I have a parts 350 with bad bearings on the final drive and if you look at the rear sprocket from the back it is easy to see the top of the sprocket tips in. Leaks oil under as well from the back of the final. You just might have bearing problems as suggested in previous posts so look for the tilt, or as mentioned earlier a loose sprocket.

But, it sounds similar to the symptoms I had.

Scott

[Scottyb]

Dave, this could also be the front roller bearings on the right track. Does not explain the foot brake being tight but worth a look.

[D.Light]

While trying to identify the source of the vibration today, I noticed the brake band anchor nut was loose. So, I tightened it real good... too good and the stud broke off. Now to try to find a T21317 anchor and replace it.....

On the positive side -- I'm hopeful the brake band was the source of the vibration and binding due to the anchor being loose.

[D.Light]

The Loader is back together now and running good. There does not seem to be any dragging or vibration after replacing the brake band. The band was a rebuilt band and some of the brake shoe material had came apart. Not sure which came first the brake dragging or the failed brake band.

Thanks for the support!