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Discussion Starter #1
so im going with 38s on my truck and was just wonder what you guys with 37s and 38s are towing cuz people keep telling me im gona ruin my tranny with those big tires. right now all im towing is a 14 ft flatbed trailer with a rzr and two quads so i know that will be fine but next year im buying a boat. should i be worried
 

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you'll be fine towing that....I towed a 64 falcon almost 1000 miles on 37" toyos with no problems on a stock trans and stock 3.73s with no problems....and this was up 6% grades with no issues what so ever.
 

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i think we are talking about long term wear and tear, not just being able to tow something.....


It will put more stress on the drive train, the brakes, and the suspension joints. It's easy to understand why.

With bigger diameter tires, it takes greater torque at the wheels to generate the same acceleration. Unless you drive more gently with a lifted truck than with a stock truck, you will have more stress on the axles, CV joints, differential, u-joints, transmission, torque converter, and engine. If you change the axle gear ratio, you can end up with no change in the stress on the u-joints, transmission, torque converter, and engine, but this won't have any effect on the axles and CV joints.

With bigger diameter tires, it takes greater torque at the wheels to generate the same deceleration. The brakes have to absorb the same amount of energy, but they have to use higher hydraulic pressure and greater force of the pads against the disks and shoes against the drums to do so. This means the maximum braking force possible is reduced.

With bigger diameter tires, the center of mass is higher off the ground. With a lift, it's higher still. This means that a greater percentage of the braking is performed by the front brakes as compared to the rear brakes, because the higher center of mass means a greater transfer of weight to the front wheels during braking. This reduces steering stability during braking and increases the tendency of the rear wheels to break loose.

With bigger diameter tires, there is greater stress on the ball joints during cornering. The centrifugal force of cornering causes the tires to exert a bending moment on the ball joints. That bending moment is higher if the diameter of the tires is higher. The same is true for the pivot joints of the upper and lower control arm.

There are good reasons why race cars are low to the ground. Everyone obeys the laws of physics. The point is that the price of lifting a truck and putting on big tires is greater than the money that comes out of your wallet.
 

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Discussion Starter #4
i think we are talking about long term wear and tear, not just being able to tow something.....


It will put more stress on the drive train, the brakes, and the suspension joints. It's easy to understand why.

With bigger diameter tires, it takes greater torque at the wheels to generate the same acceleration. Unless you drive more gently with a lifted truck than with a stock truck, you will have more stress on the axles, CV joints, differential, u-joints, transmission, torque converter, and engine. If you change the axle gear ratio, you can end up with no change in the stress on the u-joints, transmission, torque converter, and engine, but this won't have any effect on the axles and CV joints.

With bigger diameter tires, it takes greater torque at the wheels to generate the same deceleration. The brakes have to absorb the same amount of energy, but they have to use higher hydraulic pressure and greater force of the pads against the disks and shoes against the drums to do so. This means the maximum braking force possible is reduced.

With bigger diameter tires, the center of mass is higher off the ground. With a lift, it's higher still. This means that a greater percentage of the braking is performed by the front brakes as compared to the rear brakes, because the higher center of mass means a greater transfer of weight to the front wheels during braking. This reduces steering stability during braking and increases the tendency of the rear wheels to break loose.

With bigger diameter tires, there is greater stress on the ball joints during cornering. The centrifugal force of cornering causes the tires to exert a bending moment on the ball joints. That bending moment is higher if the diameter of the tires is higher. The same is true for the pivot joints of the upper and lower control arm.

There are good reasons why race cars are low to the ground. Everyone obeys the laws of physics. The point is that the price of lifting a truck and putting on big tires is greater than the money that comes out of your wallet.

do you have any recommendations on what gearing i should go with for the 38s?
 

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do you have any recommendations on what gearing i should go with for the 38s?
no, but im sure some people on here do. possibly 3.55:dunno:
 

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4.30 will get it back close to stock ,effective ratio, if it has 3.73.
 
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