BX25D Industrial Tire Replacement

[stujensen246]

The Industrial R4 tires on my 7yr old BX25D needed replacing due to the side walls cracking. I went back to the dealer to order a set of new tires. We had a mis-communication and Turf Tires were accidently ordered. Trying to make good on the tires, the dealer pulled a set of R4s from a new BX2380 which is basically the same tractor. However, when I put the new R4s on, I noticed just the rear tires were smaller in diameter.
Original tires: Circumference 82.5, Width 11.5, PSI was 18
New Tires: Circumference 79.5, Width is 11, PSI was 20
Both rims are the same size and the manufactures are the same "Garden Master" for the tires. Everything else in terms of any tire size printed on the tires are the same.

The concern here is in 4WD the new rear tires are traveling 3 inches less per rotation. After 3 weeks of going back and fourth with the dealer they are saying it should be Ok. But if a month from now, I blow something major in the drive train I know I'm going to get stuck with the repair because trying to pin it on these tires would be very difficult to prove.

Looking for Advice and your thoughts. Would you run them?
Picture of the tractor with the new tire which is noticeably smaller.

Thank you in advance for your advice.

 

[North Idaho Wolfman]

You really have 2 choices, get bigger tires for the rear or get smaller tires for the front!

 

[fried1765]

You really have 2 choices, get bigger tires for the rear or get smaller tires for the front!

Yup.
You need to maintain the OEM front to back ratio!

 

[stujensen246]

Yup. You need to maintain the OEM front to back ratio!

Thanks for the reply. The Kubota Field Service Manager my dealer is talking with is saying it's Ok to run them. However I just can't think that those front wheels are going to be spinning slightly faster than the smaller rear wheels. But I also don't know much about how that 4WD drive system is engineered. Does anyone have any technical data/information I can use to discuss with the Rep? I took the tires off and running my old ones until we resolve the issue.

 

[fried1765]

Thanks for the reply. The Kubota Field Service Manager my dealer is talking with is saying it's Ok to run them. However I just can't think that those front wheels are going to be spinning slightly faster than the smaller rear wheels. But I also don't know much about how that 4WD drive system is engineered. Does anyone have any technical data/information I can use to discuss with the Rep? I took the tires off and running my old ones until we resolve the issue.

For how many years/hours is the "Kubota Field Service Manager" willing to guarantee (in writing) the integrity of your tractor drive train ?