B2601 4WD front tires spinning

[Egressman]

Hello Friends,

I'm a bit perplexed and I think my memory has failed me. Fellow 2601 owners tell me about 4wd! Something is messed up and I'm not sure if it's my memory or the tractor? When in 4wd (Front wheels in 4wd by the placement of the lever) both front wheels are connected to the drive train and supply power to BOTH wheels in either forward or reverse! If either tire is off the ground or loses traction the opposite wheel continues to drive on under power.

The reason I am asking or stating this is, my tractor when in 4wd, on the flat ground both front tires pull me along. If one tire loses traction because of loose ground or it is off the ground it begins to spin fast and the wheel that is still in contact with the ground provides no power to keep the tractor moving!

I want to say when my tractor was newer I had power to both front wheels regardless of rather one wheel was touching the ground or not. If one lost traction the other continued to pull me forward. Is that correct?

I understand the locking differential! A locking differential when engaged "LOCKs" both axels together and power is sent to both wheels. If one wheel loses grip the other still has power. When the differential is unlocked, each wheel can spin independently.

A limited-slip differential sends more torque to the wheel with traction and the opposite wheel has some loss of traction.

Is my B2601 a limited-slip diff or a locking diff when the lever is in the 4wd position. I have disassembled the front axel, nothing is broken or wrong with it. What's the truth? Should my two front tires be locked up when in 4wd, should the trie that is in the air spin freely and NO power go to the other wheel that is still in contact with the ground?

Help me remember! My tractor used to climb hills like nothing, now is one tire loses traction I am done. We are not talking about the locking read Diff here. Just the front!

Egressman

 

[NHSleddog]

It is not either locked or limited slip. Locked is locked, limited slip will only allow a partial rotation before forcing the other wheel to engage.

The tractor (when in 4wd) is more like the power drive system. The wheel in the air can continue to spin. Most tractors DO have a locking dif on the rear set.

 

[Egressman]

It is not either locked or limited slip. Locked is locked, limited slip will only allow a partial rotation before forcing the other wheel to engage.

The tractor (when in 4wd) is more like the power drive system. The wheel in the air can continue to spin. Most tractors DO have a locking dif on the rear set.

Thanks,

The 2601 does have a rear lock. My problem is the front, I feel it used to pull me up my shooting range berm, now if one tire losses grip I am no longer able to make it up the hill. The tire that is still in contact has no power anymore, all power is transferred to the free-spinning wheel.

Egressman

 

[RCW]

Like NHSleddog said...because your front differential is not locked nor limited slip, the front wheel with less/no traction will spin.

While you can lock your rear differential, you can’t lock the front differential on most tractors. It is possible on some larger machines, as I understand it

Working as designed, unless I’m missing something.

I had a’79 Jeep CJ7 with the Quadra-Trac option years ago. A vacuum switch in the glove box locked both diffies. You only went in a straight line, but it did get you unstuck when needed.....

 

[Egressman]

Like NHSleddog said...because your front differential is not locked nor limited slip, the front wheel with less/no traction will spin.

Working as designed, unless I’m missing something.

Why are you saying it's not "Locked" or" limited Slip?" I believe it was locked when I first got the tractor. When I shift the lever to 4wd power went to both front wheels and I could go anywhere! Not the case now!

 

[RCW]

Why are you saying it's not "Locked" or" limited Slip?" I believe it was locked when I first got the tractor. When I shift the lever to 4wd power went to both front wheels and I could go anywhere! Not the case now!

Your tractor is really 3-wheel drive. Same applies for nearly all “4” wheel drive vehicles I’m aware of.

 

[RCW]

Your tractor is really 3-wheel drive. Same applies for nearly all “4” wheel drive vehicles I’m aware of.

As a follow, your tractor is really “2” wheel drive; 1 rear and 1 front, unless you have the rear differential lock engaged. Then it’s 3.

You can’t turn a true “locked” 4WD vehicle, as turning radii of the wheels would tear conventional differentials apart.

Can’t turn your tractor with the rear differential locked, as the rear wheels are forced to turn the same RPM.

Sorry to break your bubble, but that’s the way 4WD has worked for a long time. Both road vehicles and tractors.

 

[Egressman]

As a follow, your tractor is really “2” wheel drive; 1 rear and 1 front, unless you have the rear differential lock engaged. Then it’s 3.

You can’t turn a true 4WD vehicle, as turning radii would tear conventional differentials apart.

So, that being said, what happens when I put my tractor in 4wd?

 

[RCW]

So, that being said, what happens when I put my tractor in 4wd?

You have drive power to the front wheels. If both have similar traction, both will turn with drive force. Stick one in the air, and it will spin free without the other having drive force.

Same would apply to your rear wheels, absent the differential being locked.

 

[RCW]

My 1953 Minneapolis Moline is 2-wheel drive. Many tractors of the era had individual wheel brakes...does your B2601?

On a steep slope, you learned early to brake the “upper-side” wheel so it wouldn’t just spin , leaving the downhill wheel doing nothing. No locking rear differential on that.....
The wheel brakes also allowed for very tight turns while mowing hay.

 

[RCW]

I mowed this spot next to a Red Pine an hour ago with my little BX in 2WD.


It was wet and slopes left to right. Done it 1,000’s of times. Was going fast to beat the rain.

Upper wheel has less traction than-downhill side.

Obviously, upper wheel broke traction while lower did not. Same principle with your fronts. I don’t have wheel brakes on the BX, just one brake for both rears.

(I’ll also need to fix that.....)

 

[B737]

I often times wish I had a locking front differential too

 

[Magicman]

I believe it was locked when I first got the tractor.

Sorry but no, it has always had a standard (open) differential and if one front tire looses traction neither will pull.

OK, a quick test: Jack both tires off of the ground and turn one of them. If the tire on the opposite side turns in the opposite direction you have an "open" differential which we have been describing. If both tires turn in the same direction you have a limited slip differential. It can not be locked because it would be impossible to steer.

 

[Tire Biter]

Mine always worked like yer saying. So did every 4wd tractor I ever owned. If your sayin that you could climb a certain hill and now you can’t, it’s probably to do with wet or loose ground. step on the differential lock pedal and 99% of the time you’ll get going again.

 

[Magicman]

Or use the rear brakes to adjust the traction between the rear tires.

 

[Fordtech86]

Mine always worked like yer saying. So did every 4wd tractor I ever owned. If your sayin that you could climb a certain hill and now you can’t, it’s probably to do with wet or loose ground. step on the differential lock pedal and 99% of the time you’ll get going again.

Missed the diff lesson (your tractor has open axles front and rear) but to add to this, check tire pressure and maybe mark tire and rim and make sure they aren’t slipping (given this is a new traction issue on same ground). Would focus on the rear as it may have been driving it and now slipping and now you see it in the front.

 

[Egressman]

My 1953 Minneapolis Moline is 2-wheel drive. Many tractors of the era had individual wheel brakes...does your B2601?

On a steep slope, you learned early to brake the “upper-side” wheel so it wouldn’t just spin , leaving the downhill wheel doing nothing. No locking rear differential on that.....
The wheel brakes also allowed for very tight turns while mowing hay.

Yes, the B2601 has dual brake pedals, I am not concerned about the rear wheels in this scenario. I understand I can lock my rear wheels, I know I can brake one tire to shift traction, and all the other tricks with the rear wheels. My questions and issues are just based on the front axle of the Kubota B2601.

While all the information is appreciated, I am not in search of general knowledge or what if stuff.

Thanks for your information.

 

[Egressman]

Mine always worked like yer saying. So did every 4wd tractor I ever owned. If your sayin that you could climb a certain hill and now you can’t, it’s probably to do with wet or loose ground. step on the differential lock pedal and 99% of the time you’ll get going again.

Yes, the B2601 has dual brake pedals, I am not concerned about the rear wheels in this scenario. I understand I can lock my rear wheels, I know I can brake one tire to shift traction, and all the other tricks with the rear wheels. My questions and issues are just based on the front axle of the Kubota B2601.

While all the information is appreciated, I am not in search of general knowledge or what if stuff.

Thanks for your information.

 

[JRHill]

Your tractor is really 3-wheel drive. Same applies for nearly all “4” wheel drive vehicles I’m aware of.

This is absolutely true. If the back axle is locked you absolutely need the front axle on a free differential - esp if you have a load in the bucket. If you could lock both the front and rear axles you will either break things or wear them prematurely or have a handling problem.

For example, I have an old FJ40 Landcruiser. It has a ratchet locker in the back. It has a gov lock in the front. If the front has locked up due to a spin it is almost impossible to steer. Pop the clutch fwd and rev to get it free and your good to go. Try to drive it locked up and its suicide at 5mph and maybe a new front axle at the lock out.

This is the difference between 4WD and Front Assist. A true 4wd locks left and right and front left to right and front to rear. They can be really dangerous. Even in a straight line they can be dangerous.

Just me but if you are working your tractor and one of the front wheels slip you are screwed. You need more on the front to keep under control.

(BTW, the 'ol landcruiser, If I had to go to town and the roads were ice glazed, I'd never make it unless I was riding the ditch. Everything was fighting everything and nothing had traction unless I was in the ditch. Does this not make sense?)

 

[Magicman]

While all the information is appreciated, I am not in search of general knowledge or what if stuff.

OK but when you ask a question on this or any forum, that question is no longer yours but belongs to the forum. It and the responses given will benefit anyone that reads it and may very well help someone else with the same or a different question in the future. What is "general knowledge" to you may not be to the next person.