The Combine Forum banner
1 - 17 of 17 Posts

· Registered
Joined
·
790 Posts
Discussion Starter · #1 ·
After several failures including our own tractor our local dealer is recommending checking the bearings on your diffs after 8,000 hours to check for play. They are recommending doing the bearings on the diffs after 9000 hours due to multiple failures in tractors overs that amount of hours. The cost is bad just for the bearings, but the cost if they go out is terrible.
 

· Registered
Joined
·
53 Posts
When running on hills you should have them checked every year. Get up in the area of .008 in. I would definitely consider taking them out and hopefully just rehearing the axles and reshim. Any more play than that and left alone you will have issues. Bearing failures deposit the metal into the difference housing which is through the carrier bearings which is not good for them. If caught early enough you can avoid a complete rebuild. It's just the price we pay for running on the hills. Not the tractors fault nor design. I would be grateful they lasted 8k hrs.
 

· Registered
Joined
·
790 Posts
Discussion Starter · #7 ·
9632, its not just guys that have a lot of hills, its tractors that run on mostly flat ground as well. I think it is a design problem because the other color machines in the area with the same hours are having no issues at all. Personally I think it is crap that the diffs on a tractor will not outlast the motor. Don I'm not sure what to make of your comment, but if it was meant to be funny I don't consider a 20K plus breakdown very funny. To make it worse 30 hours before the front diff failed the clutch had to be replaced due to a broken disk, which the dealer had never seen happen. All together that tractor has cost about 40k this year in repairs.
 

· Registered
Joined
·
790 Posts
Discussion Starter · #9 ·
That's what I thought just been one thing after another, long year so far. We average about 600 hours a year on each tractor. **** I know guys that put 500 hours a year on a combine.
 

· Registered
Joined
·
3,776 Posts
Just doing the front diff on our 8970, the bolt for the yoke on the pinion shaft came loose this spring, I noticed the vibration in road gear so I tightened it up good and proceeded to forgot about it, stupid me... Did one bearing on the front axle two years ago. Probably hadn't been greased for a few years before, I didn't know how much grease I could give it so I was careful. After having it apart I give them twenty pumps each greasing now you can't over grease them.
I better check the 9400, I see the local dealer had a couple in last winter for bearings.
 

· Registered
Joined
·
3,684 Posts
I double checked in the operators manual for the 88/8970 and they give an hour interval of 500 for the axle bearings, yet if in wet conditions to lube them every 10 hours. I may be greasing too often but I cut the 250 hour greasing interval to 125 and just do the axles at the same time ( I grease the articulation pins every time I fuel up as those two are 10 hour grease zerks ) Knock on wood I haven't had any known issues with the axle bearings yet so I'll probably keep greasing them more often then what JD claims is sufficient. It would be interesting to find out if lack if grease/not greasing often enough or dirt finding its way in because of a seal running dry is the reason for the dealer finding the need to replace bearings.
 

· Registered
Joined
·
931 Posts
My 9330 front axle bearing failed last year at 1500hrs was around $9,000.00 to do one side. By the time I drove it the 15 miles home after the repair I had lost all the hyd oil into the trans they put the brake piston seals in wrong so it had to go back in and be taken all apart again.
 

· Registered
Joined
·
790 Posts
Discussion Starter · #14 · (Edited)
The 9000 series diffs don't have grease fittings. Our dealer said 8 grand to just do the bearings in the rear diff which we are going to do this winter after having them check the axial play to make sure it is alright for now. The only thing they saved in the front was the ring and pinion and it still was 24k.
 

· Registered
Joined
·
3,776 Posts
I double checked in the operators manual for the 88/8970 and they give an hour interval of 500 for the axle bearings, yet if in wet conditions to lube them every 10 hours. I may be greasing too often but I cut the 250 hour greasing interval to 125 and just do the axles at the same time ( I grease the articulation pins every time I fuel up as those two are 10 hour grease zerks ) Knock on wood I haven't had any known issues with the axle bearings yet so I'll probably keep greasing them more often then what JD claims is sufficient. It would be interesting to find out if lack if grease/not greasing often enough or dirt finding its way in because of a seal running dry is the reason for the dealer finding the need to replace bearings.
There is a seal at the planetary and a seal on the axle, you could pump five gallons of grease into there before it would come out a seal, I think on the 9000s all they did was eliminate the inner seals so the bearings are now oil bath.
 

· Registered
Joined
·
790 Posts
Discussion Starter · #16 ·
Well the nightmare that is this tractor continues. We got the rear diff out and torn apart only to find a broken tooth on one of the stubshafts going into one of the planetary sets. There is an update for that shaft which also requires replacing the entire planetary set. Turns out we would have been better off to just run it till it blew up, would have been the same difference. So now this tractor will have cost us 60k this year in repairs. It has been maintained by the book its whole life and this is the thanks we get. I think this will likely be the last John Deere tractor my farm will ever see, I've had it with this bullshit!
 
1 - 17 of 17 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top