E to C load range tire (BFG KO)
07-30-2014, 02:56 PM
#11
Senior Member
Tires, wheels, and much of the suspension is unsprung weight. Unsprung weight is 10 times more impact when it comes to performance of a vehicle. This includes fuel efficiency, acceleration, handling.
Example a single tire 10 lbs is equivalent to 100 lbs in the bed of the truck for considerations of vehicle performance. 10 lbs a tire times four tires is equivalent of carrying 400 lbs in the bed.
Other factors with E load range tires compared to C. There are more plys present the ride will be stiffer. Load range E will provide more lateral stability when towing. Typical heavy load E tires will typically go beyond the specifications of compression and rebound for the OEM shock valving calibration, thus your ride compliance will likely suffer.
Another option would be an XL load rated tire, slightly more load capacity, roughly same weight as OEM C load range tires. The XL will be a compromise between C and E, more toward the C side of the load scale however. XL tires aren't widely available in sizes, thus finding a set can prove to be difficult.
Example a single tire 10 lbs is equivalent to 100 lbs in the bed of the truck for considerations of vehicle performance. 10 lbs a tire times four tires is equivalent of carrying 400 lbs in the bed.
Other factors with E load range tires compared to C. There are more plys present the ride will be stiffer. Load range E will provide more lateral stability when towing. Typical heavy load E tires will typically go beyond the specifications of compression and rebound for the OEM shock valving calibration, thus your ride compliance will likely suffer.
Another option would be an XL load rated tire, slightly more load capacity, roughly same weight as OEM C load range tires. The XL will be a compromise between C and E, more toward the C side of the load scale however. XL tires aren't widely available in sizes, thus finding a set can prove to be difficult.
That extra 10# each acts like spinning freewheels. They take more energy to start and stop spinning.
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3.3XL4x4 (04-06-2021)
10-21-2020, 09:00 AM
#12
Someone above mentioned load inflation tables. That is the place to start. You can find them all over the internet, they address load rating by tire size and inflation pressure. First, look at the sticker the auto manufacturer put in the door jamb. They list a tire load rating they used to meet a specific tire load target for the OE tires. For our F150s generally, they use 35psi, which gives the highest load P rated tires can handle. At this pressure, the tires can exceed the load that the trucks axles can carry - so a bit of a buffer is built in just in case the owner overloads his truck. The tires have a maximum pressure that is higher, yes, but pressure higher than 35 does not increase the P tire's load capacity. Next, look at the load inflation tables for the tires you plan to switch to - find the psi that matches the load the manufacturer targeted. This is the proper tire pressure you should use as recommended by Ford and the tire industry. As example, my new tires are Goodrich E rated KO2s, 275/65/R18. To best match the original load capacity, I should inflate to 46 psi. Furthermore, while this pressure gives a very firm ride, it also has eliminated the understeer that my truck had with the P rated tires at 35 psi. I am very pleased with the results.
10-21-2020, 09:16 AM
#13
Senior Member
Seems most people just start a new thread on the same old topic.