Tires Poly/Foam Filled Tires

[norcal]

Looking at used tractors which have foam in the tires. These were rental tractors and the foam is used to prevent flats. I was planning on filling the tires, Ag's, with water for better stability. Im just not sure if the foam filled tire is an advantage over water filled. From a flat tire perspective sure, but how about from a lower center of gravity perspective (I mention this because watered tires are only filled 3/4 so the weight is lower). Or from a wieght perspective - does water weigh more than foam? The dealer said the foam weighs more - is this more salesman stuff... And lastly, the footprint size or contact size of the tire with the ground. Seems like a watered tire would be more pliable therefore has more contact with the ground for better traction. TIA!!

 

[MarkV]

From what I understand there are different types of foam fill with different specifications. Some of them are heavier than water fill and the idea of no flats is very appealing. The unappealing element to me is that some types of foam are known to have very little flex and that means a very rough ride. I would have to let the seat of my pants make the judgement.

MarkV

 

[_RaT_]

We have foam filled front tires on a older Ford 4WD tractor. When the tire wears out, we have to throw the rim and tire away or cut the thing apart ourselves. We don't get flats, but I really think the traction is inferior and consequently, they seem to wear faster. As far as center of gravity, I just don't think its going to make that much difference. If it does, your already very close with either one to doing something you shouldn't. For some, foam fill is the only way to go since flats can be a real work stopper. This is particularly true within construction areas and why rental agencys like to just fill them and eliminate the hassles of disatisfied customers who got the flat but feel its not their job to pay or repair it and often want credit for the time they loose. I have yet to even ballast my new tractor and at this point see no reason to do so. Pulling an extra 1000lbs up the hill for my uses just doesn't make sense on a relatively small tractor. If dirt work was all I did, they would be filled with water.

 

[Anonymous Poster]

<font color="blue"> Looking at used tractors which have foam in the tires. These were rental tractors and the foam is used to prevent flats. I was planning on filling the tires, Ag's, with water for better stability. Im just not sure if the foam filled tire is an advantage over water filled. </font>

Hi,

Foam around here is on the dense side apparently, and weighs more than water they tell me [and I believe it after feeling the weight of my front tires after foam filling].

The difference between foam and water as far as the affect on the overall center of gravity is probably a moot point. With water the center of gravity of the tire will be slightly lower than the axle, due to the air space, but the foam filled tire will be a little heavier...probably equals out in the end.

Rat's point about traction is interesting. The foam filled tires will probably not deform much...but you could run lower pressure in a water/liquid filled tire and increase the contact patch improving traction. The foam tire will probably just be a "what you have is what you get" situation. No option to run different pressures...

Personally I would not worry too much about the tires being foam filled. I know my rear R4s at 12 psi do not seem to flex out much if any even with my backhoe on [Kubota B2910].

I filled my fronts because of punctures from glass in one area I was cleaning up. Seems like the people who lived here years ago use that place as their dump, back before trash pick up was common.

If punctures on the rear were common I would be back at the shop getting my rear tires foam filled too.

Personally, if I were buying a used tractor and it had foam filled tires I would consider that a positive...as long as the tractor was in good condition. Hopefully the need for foam tires on the tractor is not also an indicator of abuse by the former users...

 

[19th_VA]

The newer types of foam, particularly superflex by Arnco, is actually a thick gel, and is supposed to approximate the properties of an air filled tire. The old foam apparently was very hard, made for industrial use, and had the problems mentioned, including a rough ride and possible damage to the steering mechanisms on lighter duty tractors.

 

[Anonymous Poster]

How does the gel stuff react to cold/freezing ? Does it get stiff or freeze in cold weather ?

 

[Anonymous Poster]

Look at the following link. It says it's good for -70F.

Arnco Superflex Foam Fill

 

[19th_VA]

It's hard to imagine it would not get thicker in the cold, but as the link above suggests, I'm sure it would not freeze either.