Replacing front tire - need to do the pair?

[Skidude108]

The tractor I bought last fall has a brand new tire on the front right, but has an older tire on the left. The seller told me I should really buy a new tire for the left so they match and don't wear out the diff.
I know that is a thing on road cars, but I just use this tractor on gravel and in the woods, and it never leaves my property. The front diff is open I think, so does it really matter if the diameter of the front tires is different by a few fractions of an inch?

 

[mcfarmall]

No.

 

[Skidude108]

Perfect, thanks! I didn't think it would matter on an open diff on a tractor used off-road but figured it couldn't hurt to ask.

 

[William1]

If one was bald and the other new, then I'd do it. But say, one is new and the other has 200 hours on it? No problem.
Even a car, there has to be significant wear from side to side to make difference. Many people drive around with several psi difference in the four tires, which is not much different than a lot of wear. No biggie.
Pencil tire gauges are only accurate with a variance of 5 psi +/-.

 

[Skidude108]

There is definitely a visual difference between the two, but it's more that the older tire has more rounded treads and the new one still has the nice squred-off tread lugs. I could probably measure the tread depth, I do have a gauge for that. Next time I'm at the compound I'll give that a look.

 

[fried1765]

There is definitely a visual difference between the two, but it's more that the older tire has more rounded treads and the new one still has the nice squred-off tread lugs. I could probably measure the tread depth, I do have a gauge for that. Next time I'm at the compound I'll give that a look.

How old is the tire?
I would probably not replace it, since at a maximum, that tractor would seem to be less than 16 years old, and the rubber should not yet be rotted.

 

[Skidude108]

The tractor is from 2010, so that's the oldest the tire could be. I actually haven't looked at the date stamp on the tire.

 

[GreensvilleJay]

Are the two tires the exact same make/model/size ?
THAT is important. I had 2 , 5.80x12 'boat trailer' tires here NOT the same,even though on same rims, same PSI.....Over an inch difference in height !!

Tractor age (2010) doesn't mean tire is 2010.... could have had a flat in 2011, tire guy tossed on a 2007...
Anything is possible.

 

[mikester]

Leave it in 2WD on hard surfaces

Put the wheels side by side, if there is a noticeable radius difference you may decide to replace the old tire.

 

[NoJacketRequired]

One can just jack up the front of the tractor (use the FEL for this purpose if so equipped) and use a tape measure to measure the rolling circumference of the tire. The measurements of left and right tires should be fairly equal. I've had to do this when matching an older tire (no longer commercially available) with the only new replacement tire I could find. In the end I bought two new front tires on rims.

And that brings up another point... Don't forget that buying tires through your Kubota dealer is tricky. One can buy the tire, one can buy the rim - both of these transactions would go through the parts department. OR... One can buy the tire on the rim! This transaction goes through the sales department as this assembly is considered to be "whole goods".

The last time I purchased rubber from Kubota the "whole goods" pair of tires on a pair of rims cost me less than either a pair of rims or a pair of tires would have cost. Whole goods are considerably cheaper than piece parts!