COG Questions
New to TCs and researching my first purchase. I've recently read about COG and I have seen it measured in numbers such as .54 etc. does the mean the center of gravity is 4" in front of the rear axle? ...
Forum Discussion
Maybe being a vintage guy and going to one of the old schools my COG (TC definition) is pretty simple to figure out.
With no TC loaded, at the wheel center (approximate) measure from the fender wheel well opening to the ground at all four wheels. Load the TC, and measure again. Compare the measurements.
1 If the loaded front measurement is less than the non-TC measurement. This indicates the COG is in front of the rear axle. This is preferred.
2 If the loaded front measurement is the same as the the non-TC measurement, the COG is directly above the rear axle. This may not be the best for steering comfort, but it is okay.
3 If the loaded front measurement is greater than the the non-TC measurement, the COG is behind the rear axle. This is not good. Depending on how far behind the rear axle the COG is, it can result in bad steering manors.
Weight distribution not only affects the handling charistics of the truck, but also headlight adjustment. With each of the above conditions, the rear axle will be carrying most of the weight. Due to this fact, the rear of the truck will squat more than the front. Just how much will be determined by your rear springs and how much the COG is in front of the rear axle. Consider this. Your headlights are adjusted without a load, therefor when the rear squats the headlights will be out of adjustment. Typically, they will be aimed higher than they should be. Will it be too much? Overload springs will not prevent this, but should reduce the amount of drop in the rear. Only something that is adjustable to bring the rear height back for correct headlight adjustment, airbags. The TC design and how it is loaded may put much more weight on one side of the truck than the other, with the result being a side to side tilt of the truck. This can also be corrected with the airbags.
Wayne
With no TC loaded, at the wheel center (approximate) measure from the fender wheel well opening to the ground at all four wheels. Load the TC, and measure again. Compare the measurements.
1 If the loaded front measurement is less than the non-TC measurement. This indicates the COG is in front of the rear axle. This is preferred.
2 If the loaded front measurement is the same as the the non-TC measurement, the COG is directly above the rear axle. This may not be the best for steering comfort, but it is okay.
3 If the loaded front measurement is greater than the the non-TC measurement, the COG is behind the rear axle. This is not good. Depending on how far behind the rear axle the COG is, it can result in bad steering manors.
Weight distribution not only affects the handling charistics of the truck, but also headlight adjustment. With each of the above conditions, the rear axle will be carrying most of the weight. Due to this fact, the rear of the truck will squat more than the front. Just how much will be determined by your rear springs and how much the COG is in front of the rear axle. Consider this. Your headlights are adjusted without a load, therefor when the rear squats the headlights will be out of adjustment. Typically, they will be aimed higher than they should be. Will it be too much? Overload springs will not prevent this, but should reduce the amount of drop in the rear. Only something that is adjustable to bring the rear height back for correct headlight adjustment, airbags. The TC design and how it is loaded may put much more weight on one side of the truck than the other, with the result being a side to side tilt of the truck. This can also be corrected with the airbags.
Wayne
