lennypoulin
New member
I lost the 4 wheel drive (front wheels) on my 1986 John Deere 855. Thanks to other posts on this site, after jacking up the tractor, front and rear, I physically looked at the drive shaft, while running and engaged, to see if it was turning.
The drive shaft is covered with a plactic outer tube and rubber boots at the U-joints. So, you have to first loosen the rubber boots, both ends and slide back to view the u-joints. The u-joint of the driveshaft was turning at the hydraulic transmission, but not at the front axle. I couldn't find information anywhere on how this u-joint comes off! No bolts anywhere, splines on both ends. I finally discovered that you have to turn the shaft to locate a split tension pin, viewable through a u-channel opening on the boot collar, and with a good punch, drive out the pins on both sides.
My problem was a sheared pin on one end only, and the driveshaft pipe rotated freely in u-joint yoke, thus not engaging the front axle. I found the right diameter tension pin at Lowe's for $0.39 cents. Easy fix, if you know how to take off the driveshaft.
If anyone else has this problem, look at the driveshaft first before digging into gear boxes. I hope this saves someone the same frustration I had trying to take off the driveshaft.
The drive shaft is covered with a plactic outer tube and rubber boots at the U-joints. So, you have to first loosen the rubber boots, both ends and slide back to view the u-joints. The u-joint of the driveshaft was turning at the hydraulic transmission, but not at the front axle. I couldn't find information anywhere on how this u-joint comes off! No bolts anywhere, splines on both ends. I finally discovered that you have to turn the shaft to locate a split tension pin, viewable through a u-channel opening on the boot collar, and with a good punch, drive out the pins on both sides.
My problem was a sheared pin on one end only, and the driveshaft pipe rotated freely in u-joint yoke, thus not engaging the front axle. I found the right diameter tension pin at Lowe's for $0.39 cents. Easy fix, if you know how to take off the driveshaft.
If anyone else has this problem, look at the driveshaft first before digging into gear boxes. I hope this saves someone the same frustration I had trying to take off the driveshaft.
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