Is my rear diff lock working correctly?

/ Is my rear diff lock working correctly? #1  

General Lee

Veteran Member
Joined
Oct 13, 2009
Messages
1,400
Location
Mid-Atlantic
Tractor
Kubota L4400, B2401
I was operating the B3200 in some wet slushy muddy stuff yesterday and engaged the diff lock when needed. Both rear tires seemed to skip and jump quite a bit and really couldn't gain much traction. I felt the peddle engage because it would drop all the to the floor when it found its spot, but tires jumping and skipping had me wondering. Also I really don't notice any traction gain whenever I use the diff lock. Any thing I can look for to see if something is damaged?
 
/ Is my rear diff lock working correctly? #2  
On my B3200 I know when the diff lock is working.......I haven't experienced any wheel hop. Where you pulling or pushing some serious weight? Soon as I see the one wheel spin I stop and engage the diff lock and drive away :).
 
/ Is my rear diff lock working correctly? #3  
On my B3200 I know when the diff lock is working.......I haven't experienced any wheel hop. Where you pulling or pushing some serious weight? Soon as I see the one wheel spin I stop and engage the diff lock and drive away :).
Same here. Do you have it in Low or Higher range when you do this. Put it in Low and see if it does it.
 
/ Is my rear diff lock working correctly? #4  
I can't say correctly or not but my B3030 did the same thing last week.

I was plowing at night after a wet snow and it started to ice up. On the way up my driveway I lost traction and went for a nice ride backward about 70 feet. I stopped the tractor, engaged the differential lock for the first time that I have had the tractor and then started up the hill slowly, the lock went to the floor as I started moving and just a few feet up the hill the tires started spinning again on the ice and hopped around some. I tried twice with the diff lock and still couldn't get up. I finally ran one tire in the snow bank and made it up.

Long story short, mine did the same thing.
 
/ Is my rear diff lock working correctly? #5  
I would be that the wheel hop was the tires grabbing then loosing traction quickly again. Had the same experience while clearing snow onmy hill when the pavement flash froze and iced over.
 
/ Is my rear diff lock working correctly? #6  
I can't say correctly or not but my B3030 did the same thing last week.

I was plowing at night after a wet snow and it started to ice up. On the way up my driveway I lost traction and went for a nice ride backward about 70 feet. I stopped the tractor, engaged the differential lock for the first time that I have had the tractor and then started up the hill slowly, the lock went to the floor as I started moving and just a few feet up the hill the tires started spinning again on the ice and hopped around some. I tried twice with the diff lock and still couldn't get up. I finally ran one tire in the snow bank and made it up.

Long story short, mine did the same thing.

Wow! That's the same thing my 4WD Dodge Dakota done the other day trying to come up my drive way except I had to get my tractor out and cut some of the ice down to ever get it up the drive way. I hate that sliding backwards feeling. I believe any will hop when you hit ice but it shouldn't do it in low in snow. Ice....yes.
 
/ Is my rear diff lock working correctly?
  • Thread Starter
#7  
I had the tractor in medium range 4wd and had a decent load of firewood in my carryall box as ballast. I've been replaying the incident in my head trying to figure if I did something wrong. The only thing that may have caused it would be I was also trying to turn to stay on course in the direction I wanted to go. I know they say you aren't supposed to turned with the diff lock engaged?? Either that it was just to slippery for the differential to make a difference. Like I said previously differential has not impressed me on this tractor. I'm soooo tempted to take it back to the dealer to get some R1's
 
/ Is my rear diff lock working correctly? #8  
I had the tractor in medium range 4wd and had a decent load of firewood in my carryall box as ballast. I've been replaying the incident in my head trying to figure if I did something wrong. The only thing that may have caused it would be I was also trying to turn to stay on course in the direction I wanted to go. I know they say you aren't supposed to turned with the diff lock engaged?? Either that it was just to slippery for the differential to make a difference. Like I said previously differential has not impressed me on this tractor. I'm soooo tempted to take it back to the dealer to get some R1's

You tell that you did some things wrong that you know your not supposed to and that you were on ice but your not impressed with your diff lock on your tractor.:) And what are the R1's supposed to do differently with you doing what you know is wrong and on ice? I suspect your turning, which you admitted to doing, and know your not supposed to do, and the ice is the problem, not the tires or the diff lock. In this case it looks to me to be driver error instead of tractor or tire error.:):)
 
/ Is my rear diff lock working correctly? #9  
Diff locks aren't that complicated. If both tires are under power when it's engaged, it's working correctly. You probably had conditions too slick to have it make a difference. Zero traction is zero traction no matter how many tires you have pushing. Once you put one side in the snow bank, you increased your traction sufficiently to make it up. You may consider some chains if your icy conditions are common. I know I need some.

As for turning when it's engaged, it's fine to make longer sweeping turns. Tight turns will be difficult as the rear will try to push the front tires straight through the turn. On hard surfaces, you will experience the rear tires hopping or your inside tire will grind on the surface as it has a shorter distance to travel. This will wear your tires quickly. Hope this helps.:cool:
 
/ Is my rear diff lock working correctly? #10  
I agree with other reply, my B3200 Just digs in in the snow when I had an occasion to engage the diff lock, both wheels will spin for traction and you will go. But maybe on ice It's a different story as wheels try to find traction they graband then slip causing what you referred to as wheel hop.
Devildog
 
/ Is my rear diff lock working correctly? #11  
Turning in LOW traction situations should not harm a quality locker. They can see the same torque/stress when one tire has more traction than the other. Turning on a hard surface, especially with ballast will put alot of stress on the locker and diff components. With both of my failures theres been no mistaking it. The pedal will kinda kick back rapidly on your foot and only one tire spins. It first seems to become harder to hold in and eventually just completely quits working. No mistaking it. I think my troubles are related mostly to the b7800 linkage and the fact i use it alot pushing snow. After looking over the b3030, 3200's, etc and the years of service i've had from a 2150 I dont think any of the other b series tractors should suffer the same problem. Those machines seem to get good engagement from the linkage. I should have rockwell hardness numbers on the diff components within the month to give an idea the quality of the component. I think it will be good.
 
/ Is my rear diff lock working correctly?
  • Thread Starter
#12  
Turning in LOW traction situations should not harm a quality locker. They can see the same torque/stress when one tire has more traction than the other. Turning on a hard surface, especially with ballast will put alot of stress on the locker and diff components. With both of my failures theres been no mistaking it. The pedal will kinda kick back rapidly on your foot and only one tire spins. It first seems to become harder to hold in and eventually just completely quits working. No mistaking it. I think my troubles are related mostly to the b7800 linkage and the fact i use it alot pushing snow. After looking over the b3030, 3200's, etc and the years of service i've had from a 2150 I dont think any of the other b series tractors should suffer the same problem. Those machines seem to get good engagement from the linkage. I should have rockwell hardness numbers on the diff components within the month to give an idea the quality of the component. I think it will be good.

Reading your previous post on your differential failure is what got me thinking if I've been using my diff lock correctly. This is my first tractor so I am learning.

JohnThomas- It wasn't ice, I was in wet, slushy, muddy conditions. Maybe it was just to slick of conditions. I read how so many people talk how diff lock gets them out of a lot of trouble. With me, it seems to just dig me deeper. My bucket has got me out of trouble more than the diff lock. I'm a new tractor owner, still learning my tractor's abilities :) Then I read all the posts on the correct way to engage the differential and think, "**** did engage it when the tires were spinning to fast, or while turning". So when I got the wheel hopping while trying to get the differential to engage, I was thinking maybe I damaged something.
 
/ Is my rear diff lock working correctly? #13  
When a diff lock is engaged, and starts to hop, IMHO the travel speeds might be a tad too high. have you tried to throttle down some when it starts to hop and see if it improves? I think that as long you dont feel a mechanical disconnecting of diff locking and relocking, the hop is probably the best safegaurd from harming your tractor. Look at it this way - the rubber on the tires flexes and if it grab a decent traction area but the tractor is not moving the pressure mounts. Just like a fault that causes earthquakes- when it finally releases the engergy , the hopping is produced as the tires bounces back to shape and throws the tractor around.

In summary- I'd rather the tires absorb/release the energy then having the tranny absorb the stress. ;)
 
/ Is my rear diff lock working correctly? #14  
In most slop/icy situations the locker wont help a whole lot unless one tire has much better traction. They make a big difference though on uneven ground when one rear tire wants to lift off the ground, like going over rocks for example. Mine helps a little pushing the deep snow, I can usually push about another couple to 5 feet than if i wasnt using it. If you have to make a hundred pushes to get through the snow it helps make the job a little quicker and easier but its no day and night difference. I had chains on after the last failure and didnt need to use the locker but the chains tore up my fenders pretty good so I took them off. That was a waste of a set of expensive tractor chains. I may try to put a smaller cain on it for next winter or maybe lift the fenders or something. It was on the inside section where they rubbed. I didnt want to do wheel spacers because that also adds stress to the rear diff.
 
/ Is my rear diff lock working correctly? #15  
I think manual says to always stop before engaging diff lock. I don't always do it but I think that's the directions. I seem to remember trying to engage it when tires are turning and it won't do it to well but when the tires are not turning it slides right in. I rarely use my diff lock but until this year I'd never done snow pushing. Usually when I engaged it before was when one wheel was up in the air as I was driving thru or across something and then the world of difference thing happened, it went forward when it wouldn't with one tire in the air.
 
/ Is my rear diff lock working correctly? #16  
I was thinking maybe I damaged something.

get on your tractor and drive just one of your front tires up on something in 2wd. Something small so you dont risk flopping it but big enough to unload traction from one of the rear tires. keep your bucket low to keep your center of gravity down. Once you lose traction your high enough. Put the brake on and put a small rock or small log/stick in front of the low side front tire, the idea is to make the thing spin so make sure your in 2wd. Now release brake, push the locker and try to go. See if both tires spin evenly or if it wants to skip and pop out. Best would be to try to find a little ditch or something uneven to cross up in and unload the tires but if you cant just be careful with what you drive up on. If its something high enough and the locker works it could push you up high enough to roll so be cautious and see what you find out. I'd be surprised if yours is bad but you never know. To maybe ease your worries, when discussing the locker thing with my dad he commented. "you know how I use mine?" I hold the hydrostat wide open and slam it in there, its a kubota, it can take it." His has 2000+ hours of such hard use and it works like new. That 2150 has built farm ponds, an mx track, maintains multiple properties, runs a 5 foot brush hog mowing acres of pasture and he even uses it to pull FULL hay wagons in out of the fields to the barn. I think his is an example of the potential kubota quality. This is why I'm leaning heavily towards my linkage being most my problem. One cheap part messing up an otherwise awesome machine. So while it may be a little abusive to hold the pedal down and slam that locker in, one time probably didnt hurt it. if it still works i wouldnt worry about it. If it doesnt there could be something defective and if it makes ya feel better I had abslutely no problem with warranty work the first time around. And its starting to look better this time now too. I still dont know if their going to cover it this time but I'm feeling better about it now that i have an idea whats happening.
 
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/ Is my rear diff lock working correctly? #17  
see my locker problem thread. I talked to kubota and it appears there were some early 3200's that had the same linkage. If yours has it and it worked like mine I wouldnt be surprised if you have a worn locker.
 
/ Is my rear diff lock working correctly? #18  
on my bx 24, I never used the diff lock but tried to use it today and the foot lever wont even go down...whats the secret?
 
/ Is my rear diff lock working correctly? #19  
on my bx 24, I never used the diff lock but tried to use it today and the foot lever wont even go down...whats the secret?

Rock the go pedal while pressing the diff pedal.
 
/ Is my rear diff lock working correctly? #20  
You are trying to engage non-synchronized gears.

Almost no one under 70 has any experience with this in a car, so the difficulty in getting it done comes as a surprise.
 
 
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