Arbitrary numbers?

TTCrewmax wrote:

ib516 wrote:

It's not just rotor size that determines brake capability.

It's the overall mass of the rotor for better heat load - heavier can absorb more heat - these are friction brakes after all. It's also determined by the calipers. Number of pistons, the hydraulic pressure used to actuate them, etc. There's also different materials used for the friction pads, with different coefficient's of friction in the material.

I think this is fluff answer...of course that all matters. But assuming that the main truck manufacture's don't have their heads up their a**. Then we can assume that the heavy 1/2 tons offered have huge disc brakes with big calipers and 4 pistons per.

If that's the case then there is nothing that says a 3/4 ton will stop a load better than a 1/2 ton.

Change my mind.

Nah, keep your opinion, I'll keep mine - and my engineering degree, 22 years of collision reconstruction experience as a LEO, and being a certified expert witness in numerous criminal trials.

ib516 wrote:

It's not just rotor size that determines brake capability.

It's the overall mass of the rotor for better heat load - heavier can absorb more heat - these are friction brakes after all. It's also determined by the calipers. Number of pistons, the hydraulic pressure used to actuate them, etc. There's also different materials used for the friction pads, with different coefficient's of friction in the material.

I think this is fluff answer...of course that all matters. But assuming that the main truck manufacture's don't have their heads up their a**. Then we can assume that the heavy 1/2 tons offered have huge disc brakes with big calipers and 4 pistons per.

If that's the case then there is nothing that says a 3/4 ton will stop a load better than a 1/2 ton.

Change my mind.

TwoManyToyz wrote:
I know and thats where I am with my overage. but its only a few hundred over.

I would imagine theres a safety buffer of 10-15% that i'm in.

You can "imagine" but you don't know for fact, and can't know because the manufacturer will never divulge that information. That would put them on the hook for any liability associated with the results of overloading, regardless of how remote the possibility of such a thing happening would be. They do not want to take ANY chance of being raked over the coals for saying, "It's okay to overload."

That said, if it works fine for you, what does any of it matter? Just drive it and be happy, until you aren't, then do something about it.

IdaD wrote:

shelbyfv wrote:
Well, if it can happen with a 3500 it's obviously something to think about!

All the newer diesels come with factory exhaust brakes. I've towed in the Rockies, Sierras and Cascades with my 2015 and coming down the big grades out here I rarely use the brakes other than slowing for corners or when I need to come to a stop. My setup isn't as heavy as some at about 20k combined, but having an EB that's able to hold a set speed without using the brakes at all is a pretty big advantage.

Yes my 5.9L was pre-factory exhaust brake. You could add one from Cummins to the late 5.9Ls, but here in Canada they were ~$1800 installed IIRC.

shelbyfv wrote:
Well, if it can happen with a 3500 it's obviously something to think about!

All the newer diesels come with factory exhaust brakes. I've towed in the Rockies, Sierras and Cascades with my 2015 and coming down the big grades out here I rarely use the brakes other than slowing for corners or when I need to come to a stop. My setup isn't as heavy as some at about 20k combined, but having an EB that's able to hold a set speed without using the brakes at all is a pretty big advantage.

Well, if it can happen with a 3500 it's obviously something to think about!

shelbyfv wrote:
It would also be interesting to hear from anyone who has experienced heat related brake fade while towing with any modern truck. With tow/haul transmissions and trailer brakes it may be uncommon.

I did. Towing over the Teton Pass in WY. Had smoke coming from both front brakes despite using 2nd gear and braking intermittently. The RV brakes may not have been doing their job as they were repaired the next season when one took a dive on me. The truck was a 5.9L Cummins 3500 SRW Megacab 4x4. Weight was about 21k combined. Had to pull over and let everything cool down. Stopping on the shoulder took 2 feet on the brake pedal. Scary stuff.

^It is uncommon, unless a person is clueless, way overloaded, no trailer brakes, or just clueless.
FWIW, a 1990 1/2ton Chevy will tow 8000lbs through the mountains with no trailer brakes and not smokethe brakes.....if you know how to drive.
The dpwra (door placard weight rating anxiety) folks might say different.

It would also be interesting to hear from anyone who has experienced heat related brake fade while towing with any modern truck. With tow/haul transmissions and trailer brakes it may be uncommon.

TTCrewmax wrote:

JIMNLIN wrote:


One big fib was 1/2 tons have nearly the same brakes as a 3/4 ton. Brakes are a axle rating function at a minimum... example;
A F250 Ford with a 6k fawr and a 6340 rawr = 12340 lbs of braking performance

A F150HD Ford has the heaviest specs with a 3750 fawr and 4800 rawr = 8550 lbs of braking performance.

Lots this guy simply doesn't know but he has a opinion like we all do.

I'd like to discuss this point further because I'm a 1/2 ton guy that tows heavy.

I've always been intrigued by this very point.

I drive a Tundra and it has, when it was originally designed in '07, huge disc brakes front and rear with a very capable front and rear axle.

So the question is how are the brakes on the new class of half tons - if equal in size - not as capable as an HD equivalent?

Thanks!

It's not just rotor size that determines brake capability.

It's the overall mass of the rotor for better heat load - heavier can absorb more heat - these are friction brakes after all. It's also determined by the calipers. Number of pistons, the hydraulic pressure used to actuate them, etc. There's also different materials used for the friction pads, with different coefficient's of friction in the material.