Go BottomShifting a new JD 990
 | dlamay
Join Date: Oct 2003 Posts: 3 Geneva, Fl 
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2003-10-09 65910
I am a new JD 990 owner and I am completly satisfied except for putting the thing in any gear from neutral. If I have the engine running at 2500 rpms and depress the clutch all the way down and try to put it in any gear it grinds. Is this normal operation? It seems better if I rev the engine down to 1000 rpms or so and then put it into gear. I can understand the gears not be synchronized as my first tractor was a Ford 8N but this just doesn't seem right.
Am I missing something or do I have a problem??
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 | Chief
Join Date: Jul 2003 Posts: 4297 Southwest MiddleTennessee 
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2003-10-09 65912
First thing I would suggest is to check this out with your dealer. Sounds to me like your clutch may not be adjusted properly or the clutch is hanging up. This would be pretty unusual on a machine so new. Now if you let the clutch out in neutral at operating rpm and attempt to immediately engage a gear, you are going to grind. This is typical of gear collar shift transmissions. Usually holding the clutch in for an extra few seconds allows the gear shafts to slow down and allow a proper shift. I am not sure which is the case with your situation. If you cannot get the trans in gear without grinding under any circumstances, something is definitely wrong. Have you reviewed the owners manual for shifting gears? The manual makes an "important" box note about shifting:
Operating Collar Shift Transmission
IMPORTANT: Avoid damage! To prevent transmission damage:
· Always depress clutch pedal when changing forward travel speeds while the tractor is moving.
· Depress clutch pedal and stop tractor motion before shifting range shift lever or changing direction.
· Never rest a foot on the clutch pedal while tractor is traveling.
It also covers the free travel specs of the clutch:
Checking and Adjusting Clutch
Checking Clutch Adjustment
MX4162
1. Pull down on clutch pedal and measure the free travel distance (A) that the pedal pivots from top of stroke to the point before clutch engagement occurs.
2. Adjust clutch if free travel is greater than 25 mm (1 in.).
If not it needs to be adjusted to between 5/8" & 1".
A certain amount of grinding here and there occasionally is to be expected but the description you give leaves me wondering. Every gear shift tractor I have owned was like this. My Kubota L245would grind due to a hanging clutch which neccessitated my starting it in gear with the clutch in and never letting the clutch out in neutral if possible. My Cub 154 Loboy would grind just a little if you tried to shift too fast after depressing the clutch from neutral. (just had to clutch and wait for the gear train to come to a stop by watching the clutch assy. & then shift)
Hope I have not confused the issue more. Best bet is to discuss this with your dealer first to go over all the possible reasons and go from there. Good luck on reaching an answer and solution. Let us know what was the problem. Nice tractor by the way and welcome to the board! ....
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 | DRankin
Join Date: Jan 2000 Posts: 5116 Northern Nevada
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2003-10-09 65920
Don't take this wrong.... I had a 4100 Gear for 2+ years.... But maybe you could change your driving technique?
On an HST you need to use the hand throttle to keep the RPM's up to get proper performance. On your Gear tractor you can just use the foot throttle like you would in a car or a truck.
That way when you shift, the tractor engine is at idle and you control your ground speed with rpm's and foot throttle pressure.
When I had the 4100 Gear, I only used the hand throttle when "roading" the tractor or as a cruise control pulling grader blades and sometimes to keep the rev's up (1500 rpm)doing loader work because I didn't have enough feet and hands to do everything.
95 percent of what I did with the tractor involved using only the foot throttle as you would in a car. ....
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 | harvey
Join Date: Sep 2000 Posts: 1550 Moravia, NY 
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2003-10-10 65923
I am not quite certian why you would try to put tractor in gear at full rpm.
If you are mowing and want to make a direction change at full rpm, simply stop, clutch, cng gear and go. The transmission will do this, with out grinding. If you let out the clutch between gears you will start the transmission spinning and will have to wait for it to stop again.
Generally if you have and geared tractor, truck etc you have to let the transmission stop spinning before you can put in gear. The bigger, heaverier and faster it is spinning the longer it takes to stop spinning. Big trucks have clutch brakes to assist, little tractors do not.
Idle down if you have had tractor working at full rpm and had the tractor in neutral before you try to put in gear. ....
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| TomG
Join Date: Feb 2002 Posts: 5406 Upper Ottawa Valley
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2003-10-10 65929
My TX ranges aren't synchronized. Sometimes I 'tickle the clutch' if it won't go into gear without grinding. Overall it does work better at lower engine rpm's, which is also true for 4wd and the pto. Clutch tickling works for them too. ....
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 | itsgottobegreen
Join Date: Oct 2003 Posts: 329 Mt. Airy, MD
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2003-10-10 65939
Talk to you dealer, it shouldn't do that. I use to run a JD 1070 w/loader and backhoe. It never did that. It did jump when you let the clutch out to fast, but thats probly because of the weight of the backhoe. If it that new, it probly has a factory defeat. ....
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| Chief
Join Date: Jul 2003 Posts: 4297 Southwest MiddleTennessee
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2003-10-11 66025
dlamay, any word yet from your dealer or have you got an update as to what the problem is? Am curious as to what the cause of the problem is. ....
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| dlamay
Join Date: Oct 2003 Posts: 3 Geneva, Fl
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2003-10-11 66050
I would like to thank everyone for the personal experiences that they have had with shifting over the years. Through much reading and searching it looks like you should depress the clutch and wait 5 seconds to move the transmission from neutral to any gear. I have done this and I am still getting some gear grinding. A John Deere repair guy is going to swing by my house next week and see what he thinks the issue is, my guess is that the second portion of the clutch that disengages the transmission needs to be adjusted.
I will post a follow up and let everyone know what the resolution is to this issue.
Thanks again,
Dan
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| TomG
Join Date: Feb 2002 Posts: 5406 Upper Ottawa Valley
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2003-10-12 66065
My experience with sliding gear TX's is that they can stop in a position where they just won't go into gear. Spinning the shafts a bit by engaging the clutch slightly will reposition things and allow shifting without grinding. But you likely know this since you owned N's and Green had a similar tractor so what's happening probably isn't normal.
I'm familiar with two stage dry clutches and the TX clutch disengages before the pto clutch and a dragging pto clutch shouldn't affect the TX unless it's out of alignment. I seem to recall that some JD's have wet clutches and there are release issues with some of them. It'll be good to hear what the JD tech says.
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| johnbilt
Join Date: Oct 2003 Posts: 1 Alaska
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2003-10-24 67025
Hi
My JD990 will do the same thing. The dealer suggested reducing the rpm before shifting into gear. I have found that when I let the tranny rev to high rpm in neutral, that it will take a few seconds to spin down after pressing the clutch.
I usually run into this problem when I set the brake, tranny in neutral, rpm's up, to jump off the tractor for a moment to grab or move something. I have found that by pressing in the clutch when I first get back into the seat, then release the brake, will give enough time for the tranny to spin down and shift into gear smoothly.
I don't have any other problems shifting between gears.
John
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| Gene Story
Join Date: Posts: 1
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2004-02-20 77360
Since the 990 has a collar shift transmission, this is one of the trade-off's you would experience versus a full synchro transmission which is much more forgiving by design to change gears in motion but of course costs more.
That said, the 990 (and 770 and other tractors with collar shift) are not the optimun tranny configuration for fast forward and reverse changes that become more typical when using a front loader for multiple load pickups. This transmission caters a bit more to continual motion field work where constant speed like used with a brush hog/mower deck is chosen. The collar shift and the more expensive synchronous transmission does typically provide a noticably higher percentage of HP to be passed to the PTO with less frictional loss/less heat versus a hydrostat coupled to the same engine.
A collar shift-equipped tractor still makes a fine tractor for loader work though; you just have to allow it to spin down some RPM before clutch-selecting a new forward or reverse gear. I personally think the 990 is one of the best compacts in it's class. It's design makes very straightforward use of mechanicals with in some cases, more substantial materials than other models and brands. The 990 & 770 have pretty good ergonomics except getting your foot around the floor shift lever and this tractor is a bit less tippy with a loaded loader bucket in a raised position than most other compacts with higher weight-center.
HST tractors - I'll add more personal input that I think very highly of HST transmission tractors too, but even some of these on the market miss the mark on optimizing the tractor for loader work. For example, you would not expect to need to increase the engine RPM to any degree when you have just Hydro-forwarded your tractor's loader bucket into a pile to then raise it up...but if the hydraulics are maybe a wee bit slow to your taste, sometimes an increase in engine RPM will get the load raised a bit faster. But on an HST tractor, this usually means you move your hand from the joystick over to the dash mounted RPM lever to raise (or lower) the RPM. Your losing some time now while messing with this. The technique can differ on different HST designes but I find that a Syncromesh transmission that has a Reverser lever, especially a Power Reverser lever, either of which is operating by the left hand is the ultimate loader tractor for the experienced person who wants to run in and out of loads with a bit more speed (safe speed, not crazy actions) while simultaneously lifting a load at the best rate the hydraulic system will provide. If this Synchronouse transmission, Reverser lever-equipped tractor also has a foot pedal for engine RPM, you've got it made---you roll into a load with right hand on joystick moving bucket level & down to ground while working speed with foot pedal. Then when material is in bucket, your left hand flips Power Reverser lever into reverse (no clutching required with Power Reverser) while simultaneously pulling back on Joystick to lift the load at a satisfying rate which you assist by pressing right foot on accel pedal to increase rearward travel rate and at the same time, get a wee bit more power on the hydraulic pump which raises the load a bit faster too. A coordinated & orchestrated operation that with experience can flow better than with an HST equipped tractor.
For most people it would be safer to use an HST tractor with loader versus trying to coordinate & orchestrate the speed with a Syncro tranny. Safer yet is the collar shift because it forces you to work a little slower to not grind gear changes before you run backwards over your dog or worse with the quicker acting Hydro or mental focus required to orchestrate a smooth & fast Synchro operation.
One more loader comment - If you have or use a NEW HOLLAND "TC" compact with factory loader, than more so than other brands, keep your eye on the loader bucket if you have it rolled completely back and then raise the loader to maximum height. These are absolutely wonderful loaders but you really really REALLY have to watch the bucket roll back position when you raise the loader all the way up. ....
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| dlamay
Join Date: Oct 2003 Posts: 3 Geneva, Fl
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2004-02-20 77366
Thanks to everyone for the advise. I did have the dealer come by my check out the "grinding" and he said that it needed to be broken in a little more and it does seem that over time it is getting better.
I will say that I am truly enjoying my John Deere!
Dan LaMay ....
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| Chief
Join Date: Jul 2003 Posts: 4297 Southwest MiddleTennessee
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2004-02-20 77372
Good to hear that you got some closure on the problem and you are satisfied with your 990. I think all of us need breaking in with our tractors when we first get them along with the tractor. I sure do. ;o) ....
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