4200 Loud in 4wd

[Deere Man]

Have a 99 4200 HST that is making a lot of noise when ran in 4wd. I don't hear it that much in A range. When I shift into B if I run faster than half speed you hear a loud bearing or geartrain type noise coming from the rear end. If you put the tractor in C It also makes the noise and you hear a click about once a second that sounds like it is coming from the left rear side (approximately). It also suck a lot of power from the tractor to run with the MFWD turned on.

Anyone have any thoughts?

I was going to split the tractor but I am confused about the process. The service manual says to split the tractor at the rear tunnell but it also says to see the differential lock procedure. The differential lock procedure says not to split the tractor but rather to pull the brake and axle assemblies off.

Sorry about the length post but I have to do the work myself and don't know where to start. It would be great if it were something easy but I fear its not. Thanks in advance.

 

[therebarely]

Does the noise sound like a hydraulic pump cavitating? You may be low on hydraulic transmission fluid, and the transmission pump is starving for intake oil. Just a thought. I am not sure if Deere used a double pump on the hydrostatic drive, but may explain why it is present in all wheel drive.

 

[radman1]

There was a known problem on the early model 4000's (4200, 4300, 4400 etc) series in the rear end. Check the archives. I believe it had something to do with shims or washers that weren't hardened. Maybe that is your problem.

 

[Deere Man]

Mine is an early 4200. How would I find the information you are referring to? The fluid levels are fine, this is a geartrain or bearing type noise. Thanks faor all the help so far.

Scott

 

[Deere Man]

It makes the clicking sound I describe when running in 2wd as well. Is there anyone that can help me find the tech bulletin that describes this or know where to find it in the archives? My search didn't turn anything up.
Thanks

 

[dfkrug]

You may be able to isolate the problem by putting tractor on
rear jack stands under the rear axle and running it in 2WD.
Operate the left and rear brakes separately to see if noise
goes away. Have a helper push the go pedal while you listen
at the rear. If it is rear end or axle, you may not have to
crack the tractor.