Rotors look small

[AcesandEights]

People will be complaining about brake fade, not knowing what it is, in a year. They'll post things like, my brakes went out while off roading, or I don't know why, but I lost all braking while out in the desert. They'll be people that are overheating them at slow speed, off road in 4-low. It'll happen.

Sponsored

 

[Beachin 74]

I went down the "better brakes" rabbit hole on my 74' w/76-77 front axle. I tried different master cylinders, vacuum boosters and calipers. Vacuum booster helped but the one thing that made a REAL difference running 33" tires on a vehicle designed for 28" tires was Hydoboost. This is where the brake booster uses the power steering pump to power the brakes.
It will now stop on a dime and give you change even with mid 1970's rotors and calipers!
I think we will be fine with what Ford uses for braking in the 6G Bronco.

 

[L8apex]

rear brakes are mostly for show anyway TBH.

Well that is simply not true.

 

[Beachin 74]

theres a reason they are smaller than the front. weight distribution is not in their favor, they do relatively little of the braking effort compared to the front.

It's even more pronounced in a short wheelbase vehicle.

 

[L8apex]

theres a reason they are smaller than the front. weight distribution is not in their favor, they do relatively little of the braking effort compared to the front.

Yes, the front rotors are larger. But cars are designed as a system, a system where the goal is to brake as efficiently as possible. The system is most efficient when all the brakes are doing the most work that they are capable of. Yes, the fronts are capable of doing more, but to say the rears are just for show is wildly inaccurate.

 

[AcesandEights]

About 70%, more or less, of the braking is done by the front brakes, meaning the fronts do twice as much braking as the rear. Not relatively little, but only about half as much as the fronts.

 

[Virtual-Chris]

I guess if the brakes are the same or similar to the Ranger, and those are working fine, then we probably have little to worry about. The Ranger is probably designed to carry a much bigger payload than the Bronco.

 

[AcesandEights]

I guess if the brakes are the same or similar to the Ranger, and those are working fine, then we probably have little to worry about. The Ranger is probably designed to carry a much bigger payload than the Bronco.

Bigger payload, but with much smaller tires.

If you think of your tires as the last "gear" in the system of gears that provide acceleration and deceleration, when you increase your tire size you decrease torque on acceleration. However, it also produces more torque on deceleration, or rather it is rotating slower than stock tires but with more force. Your brakes are trying to overcome a whatever amount, say 30" stock tire to 35" aftermarket, so 15% - 20%. Your brakes are trying to slow 15% - 20% more rotating torque.

If you think of that in weight, you're talking about having your Bronco with max payload every day on every drive (5000 lbs vehicle, with 20% load equaling the total GVWR of the Bronco as an example).

So, if you have the same rotor on a vehicle with 30" tires, and now have 35" tires (or larger), it's got to be designed for the 35" tire, and not the base model 30" tire. Either those with the base model have great brakes, or those with Sasquatch package have mediocre. Add 1k lbs payload and you're really taxing the braking system...or your not, but you should be aware of the impact of tire size on braking systems. There will be degraded performance between unloaded and loaded, and 30" tires versus 35"+. It should be a dramatic difference, just based on the amount of weight/torque that rotor is trying to stop spinning.

Off road this may be even more dramatic. Many people talk about how no one is going to be driving 100mph and trying to stop, so the brakes will be fine, but you may be putting the vehicle in 4-low and trying to stop. You are torque-multiplying, greatly, up to a 97:1 torque multiplication. You then may have taller tires, and then you're trying to stop the driveline torque and the tire size torque. That's a huge amount of torque that the rotors and calipers are responsible for limiting. For those without a lot of off road experience, as I've stated multiple times, off road you will see brake fade a lot faster than you might realize. If you're not familiar or experienced, it will seem like the brakes get overwhelmed much quicker than you might have otherwise expected.

 

[L8apex]

About 70%, more or less, of the braking is done by the front brakes, meaning the fronts do twice as much braking as the rear. Not relatively little, but only about half as much as the fronts.

1) 70-75% is under maximum threshold braking where a lot of weight has transferred to the front wheels. So hopefully not your standard braking, which would put you closer to 55-60% done by the front.
2) And under that maximum threshold braking that 60-0MPH stopping distance increases a lot if you lose 30% of your braking.

 

[KirchTX]

If we seriously are concerned with the brakes on a brand new modern vehicle manufactured by a major automaker we just need to stop buying cars altogether.

I’m not worried.

 

[Eric L]

you can upgrade brakes without putting on a larger rotor/caliper kit...upgrade the pads and get a slotted rotor...don't need to spend $3-5k.

 

[Hemisfear]

I got around it by taking a buddy's Golf R brakes (audi RS3 brakes, essentially) when he upgraded to brembo's. best decision ever. I may only be able to get 0-60 in 5 1/2 ish, but I can get from 60-0 in about 2.5 :-D

My go cart goes 0 to 60 and back down to 0 is 3 seconds...lol

 

[AcesandEights]

1) 70-75% is under maximum threshold braking where a lot of weight has transferred to the front wheels. So hopefully not your standard braking, which would put you closer to 55-60% done by the front.
2) And under that maximum threshold braking that 60-0MPH stopping distance increases a lot if you lose 30% of your braking.

I've never seen anything that stated front braking was as low as 55%, but regardless, we don't engineer braking systems for backing out of the driveway. We should be engineering them for the panic stop and the situations where we expect people to use the vehicle.

I'm not arguing that the rear brakes don't do anything, but we shouldn't be "skimping" on rotor size front or rear.

If we are all purchasing an off road beast, a Sasquatch, we should have oversized rotors designed for high-heat and long runs with people riding the brakes. That's the real world situation people expect from the vehicle, and of course the 60mph to zero.

I want better than Ranger brakes, because this vehicle isn't designed to be used in the same manner as the Ranger...or is it and we're all falling for the off road marketing schtick.

 

[wjfawb0 [hacked account]]

Looks to me like it has large six lug hubs that make the rotor diameter look small. You don't need big rotor faces if they are large diameter. The clamping and friction force being applied at a larger radius will give you more braking force. If you were going to make laps around a road track as fast as possible non-stop, you might want more rotor so you don't melt them down. I doubt the bronco is being designed/tested for high speed, long term, road track racing.

 

[nd2002]

(Anxiously awaits 'Ring times for the Bronco to be published)

Sponsored