JD 4300 Sync Reverser Transmission Problem

[JD004300]

Hi All,

Picked up a used 4300 a couple months ago with less than 600 hours. Using it today went forward and picked up a load of sandy loam with the 430 loader, went to back up with the load and the tractor did not move. I switched into forward and again no movement. When I let the clutch out I hear somewhat of a whining noise. I dumped the load to see if the weight made a difference, however, it didn't. Then I switched from B range to A which I think is low and it moves in reverse and forward without issue. I continued to use it for a while in A range until I was finished then moved it onto a level area and tried C range. C range works fine forward and reverse, switched into B range again to check it and no movement forward or reverse.


My initial thought was clutch but being that it seems works in A & C range fine somewhat rules out clutch in my mind. So my question for many of you WAY more familiar with the 4300 than I is what is your opinion of the problem and what is is going to take to fix it? I haven't had the tractor very long and am not familiar with sync reverser tractors. I do have the full service manual on DVD and am more or less capable of repairing things.

Appreciate any advice you can provide.

 

[diesel lover]

Very interesting! Best friend's dad has a 2006 John Deere 4510 with a power reverser 12x12 trans. We have used it pretty hard. He has used it a lot on his logging company! Very hard on that little tractor. With my years of experience I myself am not sure how a power reverser trans engages with out the clutch. A power shift transmission used in pay loaders and backhoes only uses a torque converter, and a hst transmission uses a verable displacement pump and a fixed motor. I would like to find out what your issue is. Are you using the forward reverse lever without touching the clutch at all? Or are you using the clutch as well?

 

[JD004300]

'I would like to find out what your issue is. Are you using the forward reverse lever without touching the clutch at all? Or are you using the clutch as well?

I am interested in finding out what the problem is too. I stopped by the local green store today, several of the service folks were dumbfounded more so as to why the other ranges work and that nothing seems to be catching or hung up. They either have never worked on one or haven't in quite some time so they were reluctant to even give me a rough estimate of hours. Sounded like they wanted to take time to tear it down for a thorough analysis. I understand their reluctance to give me a quote but I was really looking for a wag to split the tractor. I just can't afford to pay $85 an hour for someone to tinker around with it.

As to your other question, I clutch it for forward to reverse changes. I also clutch it to put it in neutral. I usually put everything into neutral before I change ranges or gears then I put it in forward or reverse. Haven't had it all that long, bought it from a source that I couldn't really trace it's ownership or what kind of life it lead. My guess is it may have had a hard 568 hours and perhaps whatever the problem is now was already in the state of coming apart when I acquired it.

 

[TCJatko]

I also have a 4300 with the Sync Reverser and 420 or so hours. Sometimes if I shift between ranges I get the same phenomenon; it takes a little "fiddling" of the range lever to get it working, as if the markings aren't quite right. I wonder if this might be the case with your machine?

Addendum: I've also heard horror stories about the range selector shaft breaking off flush with the transmission casing due to some poor engineering and having a step in the shaft for an o ring. Be careful stirring that range shifter around.

 

[JD004300]

TC, I really don't think that is the case with mine. Unfortunately I'm pretty sure I am in the range and it simply does not have forward or reverse. I was using it in the B range when it stopped working and it had been some time since I changed the range. I reconfirmed the issue yesterday. Actually checked all four gears in B range and none had movement in either direction. Very dis-heartening. Looking over the service manual it appears that the range is a transmission itself and interacts with the 4 speed. The range box appears to have three gears with varying amounts of teeth so my guess is the B range gear is maybe stripped, broken or spinning on the shaft. I guess either way the tractor has to be split in order to get to it. So I'm probably going to see what the suitability of using it in A-4. The problem I have with that thought is how much stuff is potentially floating around in the case doing additional damage to other parts, pumps etc. I will starting looking around the San Antonio Area for shop that is willing to give me a quote for splitting the tractor. As I mentioned earlier I understand the green store reluctance to quote me a price for the repair as it's unknown. However, splitting the tractor should be a quotable activity since it is a fixed and known action.

So thanks to you both for your suggestions, questions and comments. I will continue to post as I walk through this process and I hope that some of the experts reign in with their suggestions as well.

Thanks,

Steve

 

[pmsmechanic]

I'm going to go out on a limb here and say that it's either the shift forks or the synchronizer for B range. If I'm right it's going to cost more to split the tractor and put it back together than for the parts. If the gears are wore enough so that the syncronizer gets walked off of the gear then they will need to be replaced too.

 

[Tx Jim]

I agree with pmsmechanic . If I looking at parts photo correctly parts #29 is mid range gear and collar(parts key #27) must engage that gear.

 

[pmsmechanic]

Some more thoughts. You could easily do this job yourself. Buy or borrow a John Deere Service Manual. From John Deere they aren't cheep but if you Google something like "John Deere 4300 service manual" you should be able to find a cd or a down load of the manual. The manual walks you through everything step by step. John Deere manuals are about the most comprehensive manuals I've seen. If you've never done anything like this before your probably going to need someone around who believes you can do it. A friend or wife or whatever. That's probably the most important single thing. Just read, take lots of pictures, be organized, think about what you are doing and above all be safe.

 

[TCJatko]

This guy did a complete rebuild on a 4300 and should be a wealth of knowledge and advice:http://www.tractorbynet.com/forums/parts-repairs/146974-john-deere-4300-complete-rebuild-print.html

 

[JD004300]

Thank everyone for their posts. I am really considering fixing it myself but I am admittedly intimidated by the sheer weight and manageability of the two halves. My biggest concern is supporting the two halves while still being able to move them apart. I don't have a big enough place to do it inside nor do I have a gantry or lift. This would be a driveway operation, so supporting one half with bricks and wood would be ok and the other half maybe some cribbing then use a floor jack to lift it to split it then let it rest back on the cribbing while working on it. I do have a shop manual on DVD and again I have read the rebuild post a few times. Just waiting on the weather to stabilize bit here in south tx. I also thought about preparing the tractor for splitting by removing the loader and all of it's brackets, the hood, cowl, etc, following the manual guidelines of the procedure all of the way to where it's still moveable then take it to the green folks to actually do the split and pull the transmission out. Perhaps I could save myself some money for hours worth of work that I am capable of and let the pros handle the heavy lifting. Fix the machine then give it back and I can put the rest back together. I will certainly keep posting and again thanks for the encouragement.