Tire and rim change on a Kubota M9960

[LouNY]

Looking at tractor data dot com it calls for your factory rear tire to be a 18.4-30. If that is the size currently on the rears of your tractor you may get lucky.
Depending upon your brand of tires the 18.4-30 compared to a 15.5-38 may not be too different in loaded radius which would be your determining factor for lead lag.
The Titan tire lead lag calculator is here;
Lead Lag Calculator
You will need to find your tractor front to rear ratio, it may be in your manual or you may have to contact your dealer. Or possibly some Kubota guru here will know it and let you know what it is.

 

[rScotty]

Thanks guys for your responses!
LouNY is right, I do want to do row crop work. I work on a smaller vegetable farm in MA and changing the spacing of our crops is not an option. And I know that new tires and rims will be very expensive, I was just trying to find out if this would work. What do you think the front tire size should be if the rears are 15.5x38 to keep the ratio right?
Thanks

The tire information you want will be in tire mfg. specs as "rolling circumference or sometimes they call it out as loaded rolling circumference". Or sometimes just RC. I assume you are thinking about staying with the same rears and just change the front to something that fits between the rows.. Not a single trike or roll-o-matic dual, but a wide front with a different width?

On your tractor the internal ratio could be anything - sometimes it is listed in the shop specs but dont trust them. However, if you like the way it works in 4wd now, it is easy to measure the tires you have and then find a tire with the same RC.

Put a paint blob on one rear tire & and drive straight down the road in 2wd. Measure the distance between the marks on the pavement. That gives you the rolling circumference of that tire. Repeat for a front tire.
Now you can match the RC.

rScotty

 

[KubotaM9960D]

Thanks guys for your responses! I will have to see what I will end up doing.
Cole