Technical Bulletins
Tubeless Radial Rear Tractor Tires
Date: MARCH, 1993
NOTE: This bulletin replaces Firestone Field Engineering Tip #33A dated 4-20-88. Firestone has announced that all Radial Rear Tractor tires made in the USA will be identified on the sidewall, Tubeless May Be Used Tubed Type starting the first quarter of 1993. The use of tubeless tires has the following advantages:
- There is no tube to be pinched, creased, or otherwise damaged during mounting.
- There is no tube to suffer chafing failure from foreign material lodged between the tube and the tire.
- The valve cannot be torn out under high torque conditions.
- Small punctures usually result in gradual air loss rather than immediate air loss.
Mounting procedures are no different than those for tube type to physically mount the bead over the rim. Care must be taken not to damage the beads to cause an air loss.
Inflation can normally be attained by centering the tire on the rim and inflating through the valve base with the core housing removed. Use a clip-on chuck with remote inflation device to air up the tire. If the air gap between the tire and rim is too large, you may need to use an air jet ring, inflation ring, or similar device to get the tire to take air.
Tire lubricants are the same for tubeless as for tube type tires. A diluted solution of vegetable soap or approved tire lubricant is recommended.
Repairs of small punctures up to 3/8" can be plug repaired and patched on the inside. As in the case of tube type tires, section repairs can be done on large cuts or punctures. Carefully done, these repairs will retain the tubeless capability of the tire.
Hydroflation of tubeless tires is basically the same as for tube type tires. Inflate the tires to 35 psi after the beads are seated to insure that the beads are firmly in place. Deflate the tire to a minimum of 5 psi, to avoid dislodging the beads, before starting to hydroflate. Care must be taken with tubeless tires so that the rims aren't damaged or scratched. Any damage to the rim must be sanded, primed, and painted. You may want to put in a tube to reduce the potential of rim corrosion if hydroflation with calcium chloride is to be used.
If bead seepage of tubeless tire hydroflation occurs, look for the following conditions and make corrections where noted.
- Rim Damage
- Undersized rim
- Tire bead damage
- Irregularity of the rim butt weld
- Tire overload
- Foreign material between tire and rim
- Tire to rim slip
Call Firestone Sales Engineering at 1-800-847-3364 if there are any questions.