Which 19.5" tire to choose
I posted for the first time on here clear back in November of 2018. I was asking about upgrading to 19.5” wheels and tires for a 2000 Ford F350 SRW. I got a lot of good info from others here. I heard ...
Forum Discussion
2000 F-350 Single Rear wheel has a Rear GAWR of 6,830 lbs. (vs 7,850)
Are you seeking to have a 1,000 lb "safety margin" on the tires, while at the same time overloading your rear axle by 1,000 lbs? Are rear axles immune to failure?
Original LT265/75R16 tire diameter is 31.6" (vs 33" or 34" diameter).
How will the taller tires affect your overloaded truck's grade climbing ability? Will you lose an entire gear at the top end, having to resort to second when you could otherwise be in third, having to resort to first when you could otherwise be in second? If diesel, will the taller tires lug your rpms, which will increase exhaust gas temperatures when climbing? If gas, will the taller tires put you out of peak horsepower range that is generally at higher rpms with gas engines?
What effect will adding 50 to 75 more pounds per tire of unsprung weight have on the longevity of your suspension bushings? How often will you have to change dampeners? How punishing will the ride be?
Is 4,940 + 4,940 = 9,880 lbs of tire capacity needed for a steer axle that is rated at 5,200 lbs? What will that ride be like?
Can you air down steel corded sidewall tires below 80% of their minimum inflation rating (which for the Toyo M608 you are considering is 80 psi) without running the risk of overflexing the steel in the sidewall, which leads to catastrophic zipper failures when reinflated? Is that consistent with increasing your "safety margin"?
You asked for "any information you can share." I strongly suggest reading the "safety" guidelines for 19.5" tires published by the Rubber Manufacturers Association, the Tire Industry Safety Council, and the tire manufacturers themselves, including Toyo, on the risks of running 19.5" tires below the minimum inflation pressures stated on the load inflation table indices.
I've had 19.5" tires on my personal pickup for the last 20 years, btw.
Are you seeking to have a 1,000 lb "safety margin" on the tires, while at the same time overloading your rear axle by 1,000 lbs? Are rear axles immune to failure?
Original LT265/75R16 tire diameter is 31.6" (vs 33" or 34" diameter).
How will the taller tires affect your overloaded truck's grade climbing ability? Will you lose an entire gear at the top end, having to resort to second when you could otherwise be in third, having to resort to first when you could otherwise be in second? If diesel, will the taller tires lug your rpms, which will increase exhaust gas temperatures when climbing? If gas, will the taller tires put you out of peak horsepower range that is generally at higher rpms with gas engines?
What effect will adding 50 to 75 more pounds per tire of unsprung weight have on the longevity of your suspension bushings? How often will you have to change dampeners? How punishing will the ride be?
Is 4,940 + 4,940 = 9,880 lbs of tire capacity needed for a steer axle that is rated at 5,200 lbs? What will that ride be like?
Can you air down steel corded sidewall tires below 80% of their minimum inflation rating (which for the Toyo M608 you are considering is 80 psi) without running the risk of overflexing the steel in the sidewall, which leads to catastrophic zipper failures when reinflated? Is that consistent with increasing your "safety margin"?
You asked for "any information you can share." I strongly suggest reading the "safety" guidelines for 19.5" tires published by the Rubber Manufacturers Association, the Tire Industry Safety Council, and the tire manufacturers themselves, including Toyo, on the risks of running 19.5" tires below the minimum inflation pressures stated on the load inflation table indices.
I've had 19.5" tires on my personal pickup for the last 20 years, btw.
