View Full Version : D6 9U ring gear and pinion

02-09-2017, 03:25 AM
Hello everyone...I just purchased a D6 9U that needs a ring gear and pinion in the rear end. Hydraulic, with direct electric start. How big of a job do I have ahead of me? I've mechaniced since I was a kid...But this is new territory for me. Any advice would be appreciated. Thanks.

02-09-2017, 09:50 AM
Chip you might move this to the general discussion area for more response.

Walt D7-3T
02-09-2017, 12:06 PM
I moved this thread to the Discussion forum for you.

02-09-2017, 12:54 PM
You can do it, but it might be easier to get another tractor with a good gear set and move parts from yours to it! I have a couple tractors here that would be suitable and I assume they are pretty common elsewhere. Someone would have to go into a tractor to harvest a good set for you to use anyway.

You will go into it from the top, removing the seat, steering clutch booster and top covers from the gear case. Then the steering clutches and brake drum assemblies are disconnected and lifted out. Once they are out, the transmission is removed to remove the pinion shaft and then the coupling flange on the right end of the bevel gear shaft is pressed off before the bevel gear is unbolted from its hub and the bearing cages and shims are removed so the shaft can be moved to the side to allow the bevel gear to be lifted out of the case.

Then you must replace everything and adjust gear tooth contact by shimming the bevel gear shaft bearings and the pinion shaft bearings, press the clutch flanges back in place and replace clutches etc.

Procedure is covered in the serviceman's reference book for the D6 tractor.

02-09-2017, 07:37 PM
post where your from, i have a 9u tranny, bevel gear housing and track frames sitting in my yard. you could use for parts, one finnal drive is missing the internals.. engine clutch and hardnose and operator platform are removed an available. im in charlie lake b.c.

02-09-2017, 07:38 PM
Thanks Walt and CCJersey...The tractor is to good to use for parts. It's Hydraulic with direct electric start.just wanted to get an idea of what kind of job it would be.

Paso Bob
02-09-2017, 08:45 PM
Getting to and removing the cross shaft with the ring gear is fairly simple mechanics. The harder part will be the R & R of the pinion and setting up the backlash correctly.

02-12-2017, 08:35 AM
Thank you guys...I have located a couple of donor tractors for parts but wanted to see if all 8Us and 9Us take the same ring gear?

Thanks again!!

Old Magnet
02-12-2017, 10:09 AM
The 4R/5R & 8U/9U uses the same 7B9888 bevel gear but the pinion changes from 7B9887 to 9F6182 at 8U4985-up and 9U8735-up.

02-12-2017, 03:22 PM
Thank you Old Magnet...Is there a difference between oil clutch pinion shaft and dry clutch pinion shaft?

Old Magnet
02-12-2017, 03:49 PM
The change at 8U4985-up and 9U8735-up to the 9F6182 pinion came before the oil clutch. The difference is in the front pinion shaft bearing and retainer which can be upgraded with a field change over on the earlier pinion.