[ernestkroberts]

I bought a used 550 mule and it has a louder than normal whining noise that seems to come from the rear end. If you let off of the gas the noise gets a lot quieter. It runs, cranks and seems to do find with either the rear wheel locked or not. Anyone have a similiar problem or know what may be causing it?

 

[lschultz]

First thing I would do is check the oil in the rear end.Might be a bearing making noise.I got a 98 Mule 550 with 640+hrs on it. Had no problems with it other than an ongoing starter problem. Just clicks some time when you turn the key.I have replaced numerous parts and it still does it. I think it is a bad connection on a ground wire or another wire but I have not found it yet.

 

[ernestkroberts]

I have changed gear oil and it made no difference. If I go in reverse it's not loud at all so I,m thinking it could maybe be the belt is worn or a bevel gear. Any ideas?

 

[lschultz]

I would think it would be the gear causing the whine. Put a screwdriver on it and stick it up to your ear and listen to see if it is coming from the rearend for sure. Have you looked at the belt yet? How many hrs on it?

 

[ernestkroberts]

whining mule

The mule has around 1100 hours on it. It sounds great just idling. It is only when you are going up a hill that it has the whining noise. It doesn't sound noticeable going down hill and if you go in reverse you don't really hear it.