Usual Jumping out of 3rd Gear?

    The description of the common affliction for many of the D Series tractors is pretty obvious as to what happens while operating the tractor.  But what actually happens or happened to the transmission that results in the jumping out of gear?  I have read some about shifter forks?  Also gears and/collars?    Is it a chipping of gear teeth?... Wearing out a mechanical collar or bearings?.... bending of steel forks?        What usual parts are replaced to remedy the jumping out of 3rd abuse.   I have seen the estimate thrown out of about $1000 for the fix.   Just wondering what the experienced can share.      My old 1960 D-14 loader tractor is perfect but a second 1959 D-14 NF I just bought has the affliction.    It's going to be a Brush Hog tractor, so 3rd isn't used but I want to start learning a bit more about the fix.   My 1939 B winter project engine rebuild will keep me busy this year but maybe next winter.      Thanks

Gear jumping is caused by prolonged operator abuse - grinding gears, jamming into gear, not waiting for the transmission to stop before changing gears. 

I am in the process of having my third gear jumping tractor fixed now.  Grandfather's 175 was done in the late 1980s (jumped out of 3rd and 4th), my 190XT was done 3 years ago (jumped out of 4th), and my 1959 D14 is now currently in a million tiny little pieces in my neighbor's shop (jumped out of third).  There is NO CHEAP FIX that is permanent!  Some might buy some time, but eventually the transmission will need a complete teardown and rebuild.  All the tolerances that were once in the tranny go out the window.  Worn bearings on the input and output shafts cause them to move from side to side and up and down.  When this happens, the teeth do not mesh properly, so they end up getting banged up good.  A worn shift fork is not a cause of the damage, and it is not a solution either (only the 190 had a worn shift fork).  The damage to all of my tractors were pretty much all the same - bearings, gears, collars, spacers - basically replace anything that looks well worn!  Pinion shaft on my D14 had some good chunks missing from the teeth (found an excellent used one).  The 190 needed a new output shaft as well. 

Parts are not usually a problem - AGCO carries a lot of them, gears are available aftermarket.  Some of the shafts are not available new, but you can still find good used ones around.  Right now, I have over $2000 in parts for my D14 (labor has not been calculated yet), but that also includes new brakes, new bearings and seals for each final drive assembly, and some things for the rear end (might as well do it while it is apart).

While age might cause some wear in the transmission, it is not the cause of the problem.  My 1958 D14 has been family owned since 1960 and the transmission has never been touched on it and works perfectly.  When I get my 59 back, I'll see if I can get pictures of the old gears and shafts for illustration.  Safe to say, the tractor will no longer have any transmission problems for the rest of my life.


Edited by DSeries4 - 14 Feb 2014 at 10:21pm

I am doing my D14 with factory parts. My pinion shaft gears and collars were all in bad shape. I can tell you that 2000 dollar figure above is about spot on. Here is a picture of where the damage occurs, before disassembly. I will post pics over the coming days of the process.
This shows the pinion shaft, if you look carefully at the gears, you are able to see rounded edges where the collars slide over to engage the gear, it's there that the problem is usually caused, not the gear teeth themselves, also, its hard to see the teeth on the collars, but they wear as well.:


Edited by oldorangeiron - 15 Feb 2014 at 7:12am

I have a D19 that I had the transmission pinion shaft break a tooth off and that is one major disassembly! Nothing fast about it and by the time you get it torn down, you have the trans./rear end housing down to nothing. I didn't have time to do the job myself, so I took it to my local Agco dealer and they fixed it for me. Almost 5000.00! AND, I supplied all major parts! There's a lot of difference with going into a D17, for instance, verses a D19 or a 190. Lots of tearing things down, just to get to the part. On a D19, the transmission pinion shaft has all of the gears on it in the tranny and has to come out through the rear end part of the housing. Lots of fun and costly. I would think that even doing a D17, it would cost way more than any 1000.00, with replacing whatever gears needed to be changed...mainly the labor. I'd say that 1000.00 wouldn't even come close to covering the labor, unless you done the work yourself. Rick

 The pictures below are from my "CA".  The following tractors have the same trans just with a few gear and collar updates. The CA, D-10, D-12, D-14 & D-15 all share the same trans. The trans is a constant mesh type, which means that all forward gears are engaged all the time with the teeth on the outer diameter. The gear selected to move the tractor is engaged by the collar being slid over the "lugs" towards the center of the gear.

Edited by DennisA (IL) - 16 Feb 2014 at 7:19am

Dean (West MI) wrote: It would also be great to have at least the above pictures and post made into a locked sticky (pinned).

Dean,if you take the shift cover off you will see the rails the forks are attatched to.They have a notch in them for the detent ball.You basically grind the notch wider to move it and add some weld to fill in the other side of the old notch.While still in place,push the shift lever"deeper" in the gear and confirm that it travels beyond the existing notch.When you have it just right,there will be no more travel left in the lever when shoved in gear.Might take some trial and error unless you're real good at measuring and figuring.

I must have lived right, I owned 2 D17s that never jumped out and a 190XT that started not too long after I got it and it was spendy when I fixed it. Have had a 180/loader for 20 yrs that needs many probems fixed but not jumping out. Just bought a 185 and it works without a problem. Both 180 & 185 have had Clutch job, so you know they haven't had easy life. And I some times grind for third gear. With my years and hours with the D17s and 180&185 I have to have been living right. The 190XT has to have been 95+% shot when I bought it. It left home fixed for a 7020. 

First of all there is no reason to"grind" it into gear. If you've had it in neutral and start into gear and it wants to grind all you have to do is pull it back like you're putting in reverse but not all the way and then go in the gear you want. It only takes a half second and there is no grinding. When it grinds there is an idler in there that is just setting there spinning and when you go back towards reverse it stops this idler from spinning and it will go right in gear. If it grinds going to reverse just start in to a forward gear and it will do the same thing. If your tractor just "falls out" of gear going over a hump don't waste 2 or 3 thousand on a rebuild on tractor that may not be worth that much anyway. Just move the detent locations and let it gear in a little deeper and it will be fine for years to come especially with the older tractors that don't get that many hours anymore anyway. I have done several that way including my own. I have read on here that a lot of the 100 series tractors started doing this when they were nearly new, they just didn't gear in deep enough and you could order a new detent rod from AC to fix the problem. I fixed 4th on a 175 a couple years ago that had been falling out since it was nearly new. The owner couldn't believe it and he threw away his bungie cord. If I was doing a rebuild I would still move the detent locations anyway. On a d series you move the location about 90 to a hundred thousandth's each way and that is plenty. While you're at it make the grooves have a little steeper angle on them and that will help too.JP

Shifting gears without stopping is the cause of this? Are Allis tractors more prone to this than lets say red or green tractors? None of the orange ones I`ve ever owned had this issue and I speed shifted them all. CA, WD, WD-45 and now the D-17 I just bought. After this topic started, I put a loaded trailer on the 17 and ran it up and down the hill in all the gears and had none jump out. Yet. 

Dads 45 wrote: Shifting gears without stopping is the cause of this? Are Allis tractors more prone to this than lets say red or green tractors? None of the orange ones I`ve ever owned had this issue and I speed shifted them all. CA, WD, WD-45 and now the D-17 I just bought. After this topic started, I put a loaded trailer on the 17 and ran it up and down the hill in all the gears and had none jump out. Yet.

It's caused by operator ABUSE (not error) - grinding gears, jamming into gear, shifting without the clutch, anything else you can think of.

Good articles on gears.I have a D/14 my dad bought in 57 and he would get on your case if he heard a gear grind. Still have it and it does not jump out. One thing not mention is detent spring . Got a J D lawn mower went in two gears at one time and got the cluster gear because of a broke detent spring. One more thing to check.

shattercane wrote: Jack, Do you have any pictures or could you describe how the detent locations are moved? I am getting ready to tear into my 190 transmission and would like to know all of my options before spending thousands on new gears. This tractor will pull a square baler and hit a few parades when finished. Thanks in advance.

If the tranny is jumping out of gear already, moving the detents isn't going to solve the problem.  All the tight tolerances go out the window in a transmission that jumps out of  gear.  You have to put new bearings (among other things) to tighten things up in there.  In the 3 transmissions I've had to rebuild, you could move the input shaft up and down and side to side.  No cheap fix is going to solve that problem.

Sandy Lake could help you with parts.  A&I also carries transmission parts.  Most everything else I got from AGCO.