While I was plowing snow last winter with my 1980?? B7100 I depressed the diff lock in an effort to get some extra push at the end of the driveway. (I understand after reading the forum that this is not how the diff lock is to be used) Immediately a loud clinking noise similar to a tracked dozer traveling over hard ground started in the transmission area. I checked the u-joint to the front, and also checked the hubs (which are loose), but have eliminated both as the source of the noise. I don't think the diff lock works anymore, and I can't get it out of 4WD. It has never been taken out of 4WD so this could be a separate issue. I took it to a shop over the summer and they wanted $1500 to tear it apart but couldn't tell me how much more it would cost to fix. I declined to spend this amount and am back to self diagnosing. It pushed snow just fine this winter but the noise is still there and I feel like it is getting worse. I have some heavier work to do this spring that includes grading with a box scrape so I would like to fix it before it gets worse. Has anyone had this issue?
B7100 Clinking Noise
- Thread starter HardHatDaddy
- Start date
Calman93611
Member
Equipment
Kubota B7100 w/FEL & BH, Kubota B7100 w/FEL and box scraper, Kubota K008,
I have no idea what the clanking noise is however it sounds like you broke a gear. The 2-4 wd lever has a detent ball that sometimes gets "frozen" in place making it very hard to go from 2 to 4 wd and vice versa. I use to spray some wd-40 between the level and the transmission case to free the ball. Once in a while I would smack the level towards the tranny to depress the detent. Light smack ok? It only moves about 1/8 inch.
If you can get it out of 4wd then jack up the whole tractor, start it, put it in gear, 2wd and see if the front tires rotate, if they do then you are still in differential lock. Differential lock on asphalt or concrete binds the gears and makes it very hard to release differential lock. Sometimes you can go in reverse to try to relieve some of the pressure on the gears. The original B7100 came with Goodyear tires that were made to specific size because of the differential lock and because front/rear tires are different size. Goodyear only made the tires for a limited time and I think they sold the mold to someone else.
Hope this helps. In the future differential lock can only be used when the front tires are pointing straight ahead and hopefully you are on loose dirt. Try not to use 4wd on pavement, even differences in tire pressure will bind the gears.
If you can get it out of 4wd then jack up the whole tractor, start it, put it in gear, 2wd and see if the front tires rotate, if they do then you are still in differential lock. Differential lock on asphalt or concrete binds the gears and makes it very hard to release differential lock. Sometimes you can go in reverse to try to relieve some of the pressure on the gears. The original B7100 came with Goodyear tires that were made to specific size because of the differential lock and because front/rear tires are different size. Goodyear only made the tires for a limited time and I think they sold the mold to someone else.
Hope this helps. In the future differential lock can only be used when the front tires are pointing straight ahead and hopefully you are on loose dirt. Try not to use 4wd on pavement, even differences in tire pressure will bind the gears.
North Idaho Wolfman
Moderator
Staff member
Lifetime Member
Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Calman,
I'm sorry but someone totally mislead you on what the diff lock does, it doesn't have anything to do with the front end or the 4wd aspect of the tractor.
All the diff lock does is lock the 2 rear tires together.
The 4wd action of the drive system happens before the drive even gets to the rear end of the tractor which is where the diff lock is located.
Now if you step on the diff lock while one rear tire or the other is spinning it can cause shock damage to the differential and locking components but honestly that's rare.
If he jack up the tractor and put it in 2wd and the front tires or tire still spin all the means is its not in 2wd and it's still in 4wd.
There are a few model of tractors that have locking front differentials but they are much larger tractors, nothing close to the B7100.
HardHatDaddy,
First go to Kubotabooks.com and download the Ops and WSM manuals for your B7100, that will give you a better understanding on what is involved with the insides.
Take a video of the noise and post it on You Tube and put a link on here, that would really help.
Next when exactly do you hear the noise?
Forward, reverse, high, low, one gear or all gears, turning right, turning left?
Depress the diff lock does the noise change?
Get the tractor out of 4wd and see if the noise changes.
Does the noise change with ground speed or speed of the engine?
I'm sorry but someone totally mislead you on what the diff lock does, it doesn't have anything to do with the front end or the 4wd aspect of the tractor.
All the diff lock does is lock the 2 rear tires together.
The 4wd action of the drive system happens before the drive even gets to the rear end of the tractor which is where the diff lock is located.
Now if you step on the diff lock while one rear tire or the other is spinning it can cause shock damage to the differential and locking components but honestly that's rare.
If he jack up the tractor and put it in 2wd and the front tires or tire still spin all the means is its not in 2wd and it's still in 4wd.
There are a few model of tractors that have locking front differentials but they are much larger tractors, nothing close to the B7100.
HardHatDaddy,
First go to Kubotabooks.com and download the Ops and WSM manuals for your B7100, that will give you a better understanding on what is involved with the insides.
Take a video of the noise and post it on You Tube and put a link on here, that would really help.
Next when exactly do you hear the noise?
Forward, reverse, high, low, one gear or all gears, turning right, turning left?
Depress the diff lock does the noise change?
Get the tractor out of 4wd and see if the noise changes.
Does the noise change with ground speed or speed of the engine?
Calman93611
Member
Equipment
Kubota B7100 w/FEL & BH, Kubota B7100 w/FEL and box scraper, Kubota K008,
Thanks Wolfman, I've had my tractor for a gazillion years and thought the differential lock also locked the front. I got high center once, only 1 front and 1 rear tire on ground, engaged differential lock and had all 4 turning and got unstuck. So I assumed that front and rear were both locked. Good forum, even this old dog can learn something new.
HardHat-
You can use the diff lock to help with a little traction as you load up the front, nothing wrong with that. Do it all the time when using the loader, it also helps the tractor stay running straight with the load.
Where you might have an issue is dropping the diff lock in while a tire is spinning so it's best to stop, back up, engage the diff lick and re-engage the pile with the lock on so you can max out the traction and load up.
As far as what's wrong, diff locks are usually pretty simple device links and if you have the manual for the machine, as NIWolfman recommends, you can see the components involved and start checking them for damage or just sticking.
You can use the diff lock to help with a little traction as you load up the front, nothing wrong with that. Do it all the time when using the loader, it also helps the tractor stay running straight with the load.
Where you might have an issue is dropping the diff lock in while a tire is spinning so it's best to stop, back up, engage the diff lick and re-engage the pile with the lock on so you can max out the traction and load up.
As far as what's wrong, diff locks are usually pretty simple device links and if you have the manual for the machine, as NIWolfman recommends, you can see the components involved and start checking them for damage or just sticking.
Wolfman - thanks for the info on kubota diagrams. I will check out to see if I can identify anything that may be loose in the gear box clinking against the case. Possibly there is something about the 4WD linkage that is causing the noise and the reason why it won't come out of 4WD.
The noise is all the time and gets louder and faster with wheel speed. It is more noticable in reverse and gets a little quieter when turning but not all the way through the turn. Almost like there is a brief moment when the gears aren't under load which makes me think differential issue but I swear the sound seems like its forward of the differential.
The noise is all the time and gets louder and faster with wheel speed. It is more noticable in reverse and gets a little quieter when turning but not all the way through the turn. Almost like there is a brief moment when the gears aren't under load which makes me think differential issue but I swear the sound seems like its forward of the differential.