Tires spinning

[TimNY]

A question about the wheels on my Kubota b7510. I was discing a plowed field with it today and got hung up several times with some deep furrows -- a couple of tires were spinning and two others not moving at all.

I could deal with it, but what's this about?

thanks -- tim

[Tags]

Even though you tractor is 4wd it isnt really 4wd, you have differentials in the front and rear end and when one tire gets more resistance the one with less resistance has a tendency to spin. There should be a differential lock pedal for the rear end and when stepped on it will lock the rear diff, BUT, you really should to stop spinning wheels before you apply it, you dont necessarily have to but it is easier on the machine.

[k0ua]

Here you go.. this old 1937 video explains how a differential works better than anything I have ever seen. Keep in mind you have 2 differentials a rear and a front. but If you can follow this you will understand. The first 2 minutes seem worthless, but there is a purpose stay with it.


[ame=http://www.youtube.com/watch?v=F9EPf8SJc2Q]Auto Mechanics: Differential: "Around the Corner" 1937 General Motors 9min - YouTube[/ame]


James K0UA

[PHILIP8N]

Even though you tractor is 4wd it isnt really 4wd

Curious why you would say that? Then what would you call it?

[Bob77064]

Here you go.. this old 1937 video explains how a differential works better than anything I have ever seen. Keep in mind you have 2 differentials a rear and a front. but If you can follow this you will understand. The first 2 minutes seem worthless, but there is a purpose stay with it.


Auto Mechanics: Differential: "Around the Corner" 1937 General Motors 9min - YouTube


James K0UA

James that is a good video, thanks for posting.

[k0ua]

Curious why you would say that? Then what would you call it?

It is 4WD as long as the resistive/tractive forces are equal on a per axle basis. In other words, as long as the front tires have have the same load on them they will both turn. Same for the rear's. But if they are unequal on a per axle basis then it is possible to only turn one wheel/tire and the other to be stopped. I have seen many times when only 1 tire per axle is spinning, and many times when all 4 are spinning. If you use your rear differential lock you can guarantee 3 tires spinning .

James K0UA

[k0ua]

James that is a good video, thanks for posting.

Yes I was amazed how the narrator and the video start you off slow and through an easy to understand progression takes you deeper and deeper into understanding a fairly complex subject. Who say's Grandpa wasn't a good teacher!

James K0UA

[JOHNTHOMAS]

Loved the picture of the car! My first car I bought in 1964 while a Senior in HS was a 1935 Dodge 4 door sedan that looked pretty similiar to this car. Next car several months later was a 1958 Chevy Impala 348 Auto converted to 3sp in the floor. Lots of tickets 1964-65. Even got one for riding boys on the running board.
Sorry, back to 4wd.

[PHILIP8N]

It is 4WD as long as the resistive/tractive forces are equal on a per axle basis. In other words, as long as the front tires have have the same load on them they will both turn. Same for the rear's. But if they are unequal on a per axle basis then it is possible to only turn one wheel/tire and the other to be stopped. I have seen many times when only 1 tire per axle is spinning, and many times when all 4 are spinning. If you use your rear differential lock you can guarantee 3 tires spinning .

James K0UA

Thanks James, I understand the operating dynamics of 4wd, open, limited-slip, and locking differentials. I just wanted Tags to explain how a tractor is called 4wd even though it really is not, and what he would call that. Philip.

[JOHNTHOMAS]

Interesting info. I've seen men almost fight when one said they had 4wd which to them meant that all 4 wheels would turn at all times , guess I believed that in the beginning and believe most people stll believe that. Course the individual would have to get the 4wd all 4 all the time to get their vehicle and get one wheel or two on one side in mud or on ice or in a ditch to convince them that all 4 wheels do not always turn. That's about when the cursing and fighting would usually start.
I know Kubota calls their tractor or my tractors 4wd and I've often times seen that only 2 of the tires would turn (spin in mud or on ice) when in 4wd unless I stepped on the locking differential which would then make 3 of the tires turn while one was still not moving.
Philip, what would you call that? I call it 3wd.