Braking when over weight

Dayle1 wrote:

ScottG wrote:


Imagine you've got a heavy trailer in tow and you have a panic stop. The massive weight transfer at that moment will have the front of the truck doing most of the braking for both rigs. The weight of both truck and trailer will push down and try to force the front wheels of the truck to keep turning while the brakes fight it back.
The front brakes of the truck will have tremendous impact on stopping the entire combination.

Scott, if the trailer brakes are doing their job properly there will not be a massive weight transfer to the truck front axle. If anything, the trailer should try to rotate around the trailer axles, so pin weight will increase and therefore downward force on the truck rear axle would be higher and therefore greater braking capability before ABS kicks in.

I agree that there won't be a =massive= weight transfer, but there will be =some=, as the king pin is most likely ahead of the rear axle. In a perfect setup, the weight transfer would be near-equal.

What you have described is what would happen if a solo truck was carrying a full cargo load or more, then a panic stop will shift more of the weight to the front axle and unload the truck's rear axle. If a solo truck is engineered and rated to carry a certain GVWR, then a truck that is at the same load while towing a trailer should have better balanced braking performance (if the trailer brakes are indeed stopping the trailer).

Not in my experience. A properly secured load won't shift a =lot= of weight to the front axle; it will shift =some=. Now, a load that shifts, all bets are off! :B

Very few of us do panic stops, but over the life of a truck, brake pad life should tell the same story. My last truck was used almost exclusively for towing and at 100k miles still had over 50% brake pad life on it's original brakes when I sold it. I doubt a solo truck operating at or near GVWR for 100k miles would have done as well.

If the truck is stopping trailer weight (beyond the pin weight), then the setup is incorrect and stopping distance is not the only risk with the trailer pushing the truck.

I totally agree. Truck stops itself; trailer stops itself.

Cummins12V98 wrote:

Planning wrote:

Cummins12V98 wrote:
I can tell you from personal experience using the factory controller towing my 33k combined before the flash I had to hit the brakes HARD this is with the RV brakes working at no more than 50% and my pedal setting on the floor the trucks brakes are NOT designed to safely stop much more than the 16k I mentioned.

It was NOT a good experience.

I have seen a very improved braking dynamic after adding disc brakes on our 5th wheel.

I agree there is nothing better than disks on RV's. My current DRV has disk brakes that work very well now that my factory controller has had a flash.

wilber1 wrote:

MFL wrote:
While the Ford IBC does not send true ABS to the electric trailer brakes, it does have a safety control of them. When the Ford TVs brakes go to ABS, it automatically lessens the power to the trailer brakes, to prevent them from locking.

Jerry

So it reduces braking which might be a good thing but it can’t act as an ABS because it has no way of knowing if a trailer brake is locking.

MFL wrote:
While the Ford IBC does not send true ABS to the electric trailer brakes, it does have a safety control of them. When the Ford TVs brakes go to ABS, it automatically lessens the power to the trailer brakes, to prevent them from locking.

Jerry

ScottG wrote:


Imagine you've got a heavy trailer in tow and you have a panic stop. The massive weight transfer at that moment will have the front of the truck doing most of the braking for both rigs. The weight of both truck and trailer will push down and try to force the front wheels of the truck to keep turning while the brakes fight it back.
The front brakes of the truck will have tremendous impact on stopping the entire combination.