300 differential growl

I got the PTO seal ring thing in the mail Saturday and finished putting the tractor together today. I drove it about 100 feet in total and it growls pretty badly. 1st is not very audible but 2nd and reverse it is quite loud. I will tear it down again and see if I can get it better. I hope that I have not damaged the gears by driving it as far as I did. I am getting really tired of working on this tractor but I am hoping this will be the last time I have to have it apart for a while. I am thinking that maybe instead of double splitting it I may be able to mess with the shims by just pulling the hydraulic unit and top cover since I don't have to replace any gears this time.
Zach

I wish I was there helping. Jim

I'm really feeling bad for you. That thing is working your last nerve! The feeling that it will last another 60 years doesn't help when you are dirty to your elbows.

Hate to hear that. Been following your 300 project since your initial purchase with interest.

Anyway, I always heard it was an art to set up gears properly (even much simpler rear ends in cars and trucks). When its hard to do with brand new parts, then I do imagine it is only worse when dealing with used parts installed in different castings and bearings. At least your used gear set is a matched used set so hopefully you will eventually find that magic point where all is well.

(quoted from post at 23:05:49 02/03/13) I wish I was there helping. Jim

Click to expand...

Are you sure about that? Your true feelings might depend on how much heat Zach has in his shop this time a year - LOL. It has been so bitter cold lately....

Thank you for the thought. I will be using your solder method to determine backlash once I get it open again. It sounds like a neat method.
Zach

I keep reminding myself that if I can get it right it should last for a while.
Zach

Yes, I guess it is an art. I got lucky with the H I did a while back and
it was nice and quiet. Maybe next time I'll get this one right.
Zach

Yes, I was the one who indicated the pattern looked good. and I can dress for cold. Jim

yes, just top cover needs to come off, and brakes to get at shims if need to swap them. should have a magnetic base dial indicator to get accurate measurements, and a digital caliper for the shims. their quite cheap. its just a time consuming job even with the right tools. too bad you have to do it again.

Zack, I wish you the best of luck on your project. I tried the same thing on a SM and the constant whine from the gears was more than I could tolerate. I had it apart and moved shims more time than I can remember. My solution was to replace the entire rearend of the tractor with a good rearend. Problem solved.

Good luck with it Zach. I finally gave up on my rebuild and found a whole rear end and made that one better. I had pieced a bunch of things together for my H and when we drove it it sounded like a screaming banshee. New replacement rear end...drives great now.

Mark

Oh the fun of setting ring and pinion. I would try very hard to set the backlash to what the supplier measured when he took it apart. You want a toe bearing on drive side and centered in the old wear pattern. Realize also, the usable area on both gears does not extend way down to the bottom of the groove between the teeth therefore the pattern should be somewhat toward outer portion of tooth. Put a load on the ring gear and turn pinion when testing pattern. Backlash is easy to set, depth of pinion is the difficult part. Most new gears are basically flush on the heels and never should the pinion be into the ring gear beyond flush.

I doubt you've done any damage at all. Frustrating, but hang in there.

I don't know if this is any help, but I have got an extra tube of Permatex "Prussian Blue" gear marking compound that is specially formulated for just that purpose, I'll send it to you for nothing if you are interested. But let me add one other point: I bought a new 1989 Mustang G.T. 5.0. For the first 60,000 miles, the rear end was silent. After that, it started making noise. I took fantastic care of that car. Didn't drive it the way most people would drive such a car. Long story short, after endless problems with noise with new gears and a complete professional rebuild, I obtained the help of a trusted local dealer mechanic. He was able to determine that the factory, when it set it up, had installed the wrong thickness shim for the pinion depth. The other "professional" who installed the new gears, just replaced the same shim that came on it, thus perpetuating the problem. Once we installed the correct (thinner) shim, the noise disappeared, and I drove it another 120,000 miles before selling it to a friend, who is very happy with it. No rear end noise now, and the car has almost half a million miles on it. Good luck. Hugh