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redneckhippie

Rim width

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I have some 18.4-38 I would like to mount tubeless on 14 inch wide rims. Has anyone on here done this? Do I need a rim designed for tubeless tires? 

Thank you Paul

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You can squeeze an 18.4x38 onto a 14x38 rim.  A 15x38 rim is actually an approved alternate. You will have to play with inflation pressure to get the full footprint of the tire onto the ground and it will be very sensative to the amount of weight it is carrying.

 Spend the money for inner tubes!  A RADIAL rated tube, preferrably a Firestone Radial rated tube. No special tubeless rim on tractor tires.  15.5x38 and 18.4x34 tires were considered Tubeless at Farmall.  We ran about 5-6 times as many leaky tires on those two sizes in both 6 & 8 ply and R-1 and R-2-0 treads as we did on ALL the other tube type rear tires combined.  And that was with brand new tires and brand new rims and guys who mounted over 400 large rear tractor tires A DAY.  They knew what they were doing and had the right equipment.

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Thank you. I will get some tubes. Mainly a play tractor with a loader. It has old 15.5 and is about helpless in the mud. 

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16.9-38s would be a good replacement for 15.5s.  Dad did that years ago on the 686 he had just bought.  Just don’t get the long/short tread pattern that he did.  

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1 hour ago, Gearclash said:

16.9-38s would be a good replacement for 15.5s.  Dad did that years ago on the 686 he had just bought.  Just don’t get the long/short tread pattern that he did.  

Yes!  And 16.9's have 14 inch rims as first approved alternate rim width.  I don't know why most 686/H86's didn't get built with 16.9's from the factory.

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8 hours ago, DOCTOR EVIL said:

Yes!  And 16.9's have 14 inch rims as first approved alternate rim width.  I don't know why most 686/H86's didn't get built with 16.9's from the factory.

I wonder if it was a concern about the capability of the final drives and in particular the differential. The three 686's I have seen with failed differential ring gear bolts all had 16.9-38 tires on them and were used for plowing. In particular with a 720 4 x 16 plow. Similarly most 666 and 686 I have seen with 18.4-34 tires all had pressed steel rims to limit the weight for traction. I have only ever seen one 666 and two 686 with the cast iron 18.4-34 wheel centers. The most common by far was the 15.5-38 size and that limited the tractive force on the transmission and final drive. To summarize, I wonder if they weren't afraid of a repeat of the 560 fiasco.   

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2 hours ago, George 2 said:

I wonder if it was a concern about the capability of the final drives and in particular the differential. The three 686's I have seen with failed differential ring gear bolts all had 16.9-38 tires on them and were used for plowing. In particular with a 720 4 x 16 plow. Similarly most 666 and 686 I have seen with 18.4-34 tires all had pressed steel rims to limit the weight for traction. I have only ever seen one 666 and two 686 with the cast iron 18.4-34 wheel centers. The most common by far was the 15.5-38 size and that limited the tractive force on the transmission and final drive. To summarize, I wonder if they weren't afraid of a repeat of the 560 fiasco.   

I'm sure that was the reason.  But for mowing/raking hay and pulling a small square baler or small round baler the 16.9's would be fine.  Maybe even planting & cultivating, but nobody cultivates anymore.  Crawling along in 2nd gear with 4-16's is a huge load in comparison.  4-14's caught up with the diff. carrier bearings on our 450.  Not sure if they had been replaced before we got it, it was 7-8 years old when we got it, if I had to guess I would say Yes, but one in the second year we had it, other side the next year.  You could tell by the way the brakes felt.

There was an Engineering system problem with the steel disk wheels and 18.4x34 tubeless tires.  That wheel made by Motor Wheel division of Good Year in Mendota, Illinois had two valve stem holes. One got the normal tubeless tractor tire valve stem, the other one got a tapered tire valve stem hole plug from Electric Wheel.  The problem was this plug was a loose fit, meant to be used with an inner tube. For a tubeless tire a brass with rubber sealing washers plug was supposed to be used, something from Schrader Mfg..  That required a wrench or two for tightening.  Assembly wanted nothing to do with wrenches and tire plugs.  An inner tube would have fixed it but manufacturing engineering wouldn't reactivate the tube-type part numbers.  A phone call from "Denny at Farmall" would have gotten the three suppliers of 15.5's and 18.4x34's to tube them all up with maybe a quick FAX to make it official,  but I wasn't going to eat the added cost without adjusting standard costs.  So we all delt with flat tubeless tires every day.

Karma is a Witch.....  My new Cub Cadet Tank has two Carlysle 24-12x12 turf tires on the drive wheels, right tire goes flat about every ten days. Done it since brand new.  Left tire never leaks.  I think I bought an inner tube for it.  Might be a winter project this winter.  ANY tire I get thats used at less than 25-30 mph gets an inner tube.

 

 

 

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