JD 3720 power and speed reduction

Freemans · Aug 26, 2012

Have a JD3720, 1 yr, 120hrs, e-hydro trans. Suddenly one day (pushing brush in a pile) it would only move at about 10% speed that it should. Had to jack the throttle way up to nurse it back to the barn. Called the dealer and let it sit for 2 days until they could take it. When they loaded it out, it moved at about 80% speed that it should. They added a little hydraulic fluid and said that it operated within the specs.

Still operates at only 80%. I tested and it makes only 17.2mph (on the largest R4 tires) on hard packed dry flat dirt road with the throttle maxed (2700rpm). Owners manual says it should make 18.4mph. I guess that is only a couple percent speed difference and probably qualifies for the dealer to say it meets specs. BUT, it is not right, I still have to throttle up way too high to get anything done.

Anyone had this? Is there something anyone knows that may help me help the dealer in looking in the right place?

I asked them to check hyd. filter, and they basically said that if it meets specs, there is no reason to look there. I hesitate to replace myself as it is several hundred dollars on this machine for both filters and new fluid, plus it is still under warranty.

Freemans

andersale · Aug 26, 2012

Is your Loadmatch On?

dschuffert · Aug 26, 2012

A couple of things come to mind. It could be Loadmatch on or if you have the auto cruise control package you can set the maximum speed of the machine and this could be set. I have a 3720 now, had a 3520 before it, and never achieved the maximum speed listed in the manual. I have R3s on both of them. I was always about 1.6 MPH slower than the manual stated.

GreatWhitehunter · Aug 26, 2012

Turn Load match off and see if issue still persists. If it does not then you need to calibrate you throttle sensor. The repair manual outlines the process for calibration. Have both the sump and suction filter been replaces?

Matt

Freemans · Aug 27, 2012

GreatWhitehunter said:
Turn Load match off and see if issue still persists. If it does not then you need to calibrate you throttle sensor. The repair manual outlines the process for calibration. Have both the sump and suction filter been replaces?

Matt

Thanks for replies

I seem to be unable to turn the load match off, it does not want to store the command. Perhaps software glitch. Is this something that arbitrarily turns on or off while pushing a pile?

I asked the dealer to check/service the hydraulic system as stated above. Normally I would just change it out if we are talking about a $10 spin on filter,however, the dealer said the sump filter was $100, the inline was $50 and then 7 gallons of JD hydrualic fluid - ouch, all for a unit that is supposed to be under warranty.

I do not have the repair manual to reset the sensor. Perhaps a branch or something whacked it while I was pushing.

GreatWhitehunter · Aug 27, 2012

You simply turn the load match rocker switch to the off position. The display flashes load match off and then load match is off. Refer to your owners manual if you need help. The in line hydro filter can be changed without draining the sump. You'll loose a small about of hygard but nothing crazy.

All instruments need calibration from time to time. It's not unheard of to need to cal it. You need to buy the maintenance manual and follow the procedure from there. It may be helpful to find another dealer aswell.

Matt

sunnyside360 · Aug 27, 2012

GreatWhitehunter said:
You simply turn the load match rocker switch to the off position.
Matt

Yep, that's how my 2007 3720 works. However, about a year ago the local Deere dealer told me the dash switch was removed on the newer tractors -- said Load Match was turned on and off thru programming as described in owners manual. Can someone who has a newer 2010 -2012 3x20 confirm?
Just saying ........... don't know for sure.

dschuffert · Aug 27, 2012

Actually the LoadMatch feature can be turned on/off via either the programming method if you do not have the switch or by using the rocker switch if you have it. I have a 2012 3720 that has the LoadMatch switch on the dash. It is the farthest upper left switch on the dash as shown in the manual. The LoadMatch switch comes as part of the automotive upgrade kit (LVB25866) (which is an enhanced version of the standard cruise control). I added this to both my 2011 3520 open station and my 2012 3720 Cab.

The automotive upgrade kit retails for around $102, comes with four different rocker switches (LoadMatch, Cruise/Max Speed, Accel/Decel, MotionMatch), and an updated piece of wiring harness that provides additional connectors for the additional two cruise control switches. The LoadMatch switch connector is on all the 3x20 series tractors. It is behind the dash and to the left hand center of the dash for open station models, it is on the left upper part of the dash for cab models. If you are adding this package after delivery of the tractor there are some simple programming steps listed in the install instructions. The switches will not work if the programming isn't completed successfully. If the switches are added as part of the factory order they are already programmed.

sunnyside360 · Aug 27, 2012

dschuffert said:
Actually the LoadMatch feature can be turned on/off via either the programming method if you do not have the switch or by using the rocker switch if you have it. I have a 2012 3720 that has the LoadMatch switch on the dash. It is the farthest upper left switch on the dash as shown in the manual. The LoadMatch switch comes as part of the automotive upgrade kit (LVB25866) (which is an enhanced version of the standard cruise control). I added this to both my 2011 3520 open station and my 2012 3720 Cab.

The automotive upgrade kit retails for around $102, comes with four different rocker switches (LoadMatch, Cruise/Max Speed, Accel/Decel, MotionMatch), and an updated piece of wiring harness that provides additional connectors for the additional two cruise control switches. The LoadMatch switch connector is on all the 3x20 series tractors. It is behind the dash and to the left hand center of the dash for open station models, it is on the left upper part of the dash for cab models. If you are adding this package after delivery of the tractor there are some simple programming steps listed in the install instructions. The switches will not work if the programming isn't completed successfully. If the switches are added as part of the factory order they are already programmed.

Dan, many thanks for the excellent description of how the Load Match option is currently offered. My older 2007 4320 open station had the Load Match switch and did not have the automotive upgrade kit. My 2010 4320 also does not have the automotive upgrade kit and does not have the LM dash switch.

The max speed on my 3720 cab tractor is slightly less (1-2mph) than the published max speed on a level road with Load Match on or off.

Freemans · Aug 28, 2012

Thanks again, all for your experience.

This machine does not have the rocker switch for the "Load Match".

I cycle through the display mode switch and it reads "loadon"
, so I press and hold the switch until is says "release"
and then I toggle the turn signal to "coast"
I press the display mode switch again and it does not flash twice (like it does for the 'motionmatch')
As I toggle back through the settings, it shows "loadon"

When I trun the ignition again, it shows 'coast' as the last command change, but when I toggle through the options, it still shows "loadon"
I notice no performance difference.
Is it just stuck in the 'loadon' position? after acting up on a trail one day.

I would like to get this settled before I look into the throttle position sensor.
Thanks again for all replies