Tractor tire swap ??

[crsutton81]

We went to 30 inch rows a couple years ago but just got around to changing the mid size tractors tires to 14.9 x 46 last year from the 20.8 x 38 that came on them. We had already done what heavy tillage that needed done when the change was made. This is the first heavy pulling load I have tried on them, but I'm having slippage issues on the lighter land with them. Are the 20.8's near enough in diameter to temporarily unbolt the 14.9 duals and change back and run the bigger tires as a dual and leave the inner 14.9 in place ?

 

[ss55]

Most tire dealers and manufacturers post online tire dimension charts. If you had to dual the 20.8s you will probably need to dual or triple the 14.9s too.

 

[caterpillar guy]

I would doubt you could do that. The 46's will be substantially taller and probably have the 38's hanging in the air whether inside or on the out. The rim is 8 inches larger diameter and the tires will not make that up with them only being about 2inches different from rim to tread.

 

[BarnyardEngineering]

If you can figure this chart out I think the answer is there. It shows 380/90R46 (ak 14.9x46) is the same RCI, rolling circumference index, as the 520/85R38 (aka 20.8x38). At least that's how I interpret the data, and to me that means they're close enough to use together.:

https://commercial.firestone.com/content/dam/bcs-sites/firestone/PDF/RCI.pdf

 

[Cash4Toys]

Per a Firestone spec sheet, 14.9x46, 212 rolling circumference, 71.2 overall height.
20.8x38, 220 rolling circumference and 72.4 overall height. Given most manufacturers suggest lesser tire preasure on the outer dual, IMOP its a non-starter. 520/38 radials are about the same

 

[Bob Bancroft]

Most I know who are doing 30 inch row crop work with a large tractor are using 18.4x46. Could you do that? I have a tractor with
(4)20.8x42, and a tractor with (4)18.4x46. Unlike anyone else I know, I don't like the 18.4x46 for tillage. As of yesterday I have 20.8x42 to replace the 18.4x46. So I'll have (4) 18.4x46 on CaseIH wheels for sale.

 

[crsutton81]

We have a CIH 7110 and a 7120 that are the tillage fill ins and the only tractors for planting, spraying, sidedressing and such. I don't regret a bit in the world about going to 14.9 x 46 for the row crop work. I still have the 20.8 stuff and which was the thought of just temporary swapping the bolt on duals if it'd work to finish chiseling and fumigate the tobacco ground with ripper bedder. I just made my mind up when we changed wheel sizes to go ahead and get the narrowest acceptable tire for the job to alleviate the row compaction problem we were having.