Ag tires not available????? Help please.

[tiger9297]

I have a Kubota B7100HST 4x4. Right now the tractor has turf tires on the rear and basically "slicks" on the front. No, they are not worn out, but literally have no tread. Not sure what you would call them. Anyway, the front tires are 20.5x8-10. I have put a loader on this tractor, and wanted more aggressive tires. My plan was to put industrial tires on it, but they aren't available in these sizes, so I figured I just go with some "old school" ags. Well, they aren't available in the size I need for the front tires. I can't believe that ag tires are not available for the front of a 4-wheel-drive tractor. Does anyone have any suggestions???

 

[Randyj]

With 4X4 you have to make sure you have the correct sized tire & wheel. Look at your owners manual to make sure of this. Then, I would think that "Titan" would have the correct tire for your rig.

 

[Captjack]

What I would do

is go to Firestones website(because its a good site) and get the OD (OVERALL DIAMETER) specs on your current tires. Then go to the ag section and find tires that are close to that size in OD and width.
Keep in mind if you go a little bit bigger on the rear - you have to find a front tire that is the same difference from the stock front tire - in other words if you go an inch bigger than stock on the rear you will need to go an inch bigger on the front.

Should be easy to do - pm me if you need help and I can assist - spent 20 years of my life in the tire biz

 

[L4740]

This is a common discussion here. Search "tires" or "tyres" and you will find many post regarding this subject. As others have already mentioned it is very important to keep the rolling circumference ratio the same as the old tires. The problem is that ag tires (A1's) will not fit on a 10" wide rim. You will also need to replace your front rims to accommodate the ag tires. Usually a 4 or 5" rim is what they will require. Industrial tires (R4's) will fit a 10" rim, but you may not be able to find them with the proper diameter to suit your needs. In most cases, when switching from turfs to ags, it is necessary to also change your rims. Good luck
.

 

[Eric McCarthy]

Dumb question but what can happen or what damage can be done if you DON'T keep the same rolling size tires all the way around like Jack warned us about? He has mentioned if you go an inch bigger on the rear do the same for the front. Or does that just apply to 4x4's because of the front axle having torque placed on it when the 4x4 is engaged.

 

[B7100]

Dumb question but what can happen or what damage can be done if you DON'T keep the same rolling size tires all the way around like Jack warned us about? He has mentioned if you go an inch bigger on the rear do the same for the front. Or does that just apply to 4x4's because of the front axle having torque placed on it when the 4x4 is engaged.

There is a formular for working it out but when I bought my new Ags the dealer did it for me
Wind up happens when in 4 wheel drive, because there is no diff in the transfer box, so when cornering on tarmac or other hard road surfaces, the front axle takes a slightly larger turning circle than the back, so the front axle turns a few more times than the rear axle, therefore the rear output shaft will want to turn slightly slower than the front output shaft. Now as the front and rear output shafts are locked together, only one thing can happen, the shaft will try and twist, hence the name wind up. It may not be noticeable on soft ground or snow as a wheel may slip and relase the wind up.I have seen an accident when an inexperienced chap tried to undo the uj nuts after a wind up without jacking up a wheel to relase the tension and nearly lost his finger.

dave

 

[Eric McCarthy]

WOW never knew or thought of tire size causing that much of a problem. That's amazing.

 

[traildust]

WOW never knew or thought of tire size causing that much of a problem. That's amazing.

No kidding! Never thought about this either

...I have seen an accident when an inexperienced chap tried to undo the uj nuts after a wind up without jacking up a wheel to relase the tension and nearly lost his finger...

Scott