Extending brake life- Stomp, or squeeze!

When SVreX said that he was driving 9k pounds, I missed the word truck and assumed that he was just driving an SVX.

In reply to snailmont5oh:

That's really funny.

No, my old 5 spd SVX was a JOY to drive on this road!

I don't know a dam thing but seeing that you are hot climate, it would seem that anything you could do to improve cooling would be wise for heat dissipation which should result in less wear.

So, can you add cooling ducts to your truck?

z31maniac wrote:

Furious_E wrote: I'm thinking gentle squeeze and, without going too far down the rabbit hole, here's why: We all know the job of the brakes is to basically convert kinetic energy to heat, then dissipate that heat. To shed a given amount of speed, you've got to generate the same amount of heat, regardless of the time interval. Dumping all that heat into the rotors/drums in a short interval (hard and late) gives it less time to dissipate that heat, thus they get hotter that way. Assuming more heat leads to faster wear, hard and late should wear them out quicker. Now, that's neglecting to factor in how things like vehicle speed and temperature differential affect the heat transfer from the brakes to the air, but my theory seems to agree with practical experience.

You're actually completely opposite. That's why race cars try to compress the braking zone as much as possible, so there is more time to dissipate the heat from the previous corner.

But were not talking race cars here but trucks! I have to agree with the first post. I also road race and the reason we brake late is not to preserve the brakes but to maximize acceleration time and minimize braking time. Also in racing we brake from the point of maximum speed we can attain on that straight. The posters truck is not driven that way. Less speed, less heat to reject.

IF the truck were a manual, compression braking would help quite a bit. I have driven both an auto and a manual and a manual offers more effective compression braking since it has a direct link to the rear wheels and not a torque converter in the mix like an auto trans.

Bottom line (from a thermodynamics/physics standpoint), it will take the same amount of energy/heat to maintain downhill average velocity regardless of how you brake. If you start at the top of the hill at 35 mph, and get to the bottom of the hill at 35mph, it doesn't really matter if you brake hard or soft. It will still require the same amount of kinetic-to-heat energy conversion to accomplish it.

This assumes things like not using any accelerator in between curves, and equal gross weight.

Brakes do wear faster when really hot. If you are doing a 50-0 stop with cold brakes, they will wear a wee bit less than the same stop with screaming hot brakes, but this phenomenon doesn't typically occur until they're really hot... as in smelling like an electrical fire hot.

So I don't think that the type of braking is causing more or less pad wear.

I would however argue that sharp changes in temperature do cause more wear to other things. Cast iron is a bit happier with gradual temperature changes, so I might argue that soft, continual braking might contribute to overall brake "happiness" more than hard braking: Easier on suspension bushings, chassis, calipers, rotor heat fatigue, etc.

Electric trailer brakes are really cheap. IIRC $40/axle. Put good tires on the trailer and drag them the whole way :)

In reply to Huckleberry:

Right.

An anchor is even cheaper.

I think some of you are assuming downhill out of control, like OMG runaway truck ramp time!!!

The point is, I LIKE driving this road, and 9K is NORMAL for me.

So, the issue is both uphill and downhill, and there will definitely never be a time I don't accelerate between corners. Picture mildly spirited driving, not hill climb.

I have this road memorized, and generally run faster than other people driving it, either up or down (exception- crotch rockets). But I've never been to the point of burning the brakes in 15 years.

So, the question was a general thought- Gee, I wonder which way of driving this road will lead to a little more brake life.

In reply to curtis73:

Good word on the other components.

In reply to SVreX:

You haven't priced big-ass anchors, have you? You'd need a pretty big one to slow down your rig.

I'm in the "brake harder, shorter" camp. Gentle braking retains more heat, warps rotors, boils fluid; none of which I'd want happening when I'm coming down a hill at 9000 lbs.

EDIT: After pondering this, this method would potentially lead to faster brake wear. Think of taking your DD to a track day. Hard, short braking, but you've chewed up your pads pretty good, as opposed to them lasting a long time doing your daily commute with gentle braking.

RealMiniParker wrote: EDIT: After pondering this, this method would potentially lead to faster brake wear. Think of taking your DD to a track day. Hard, short braking, but you've chewed up your pads pretty good, as opposed to them lasting a long time doing your daily commute with gentle braking.

I'm sure you're braking from lower speeds and less frequently on your commute though...

In reply to GameboyRMH:

A good point

RealMiniParker wrote: I'm in the "brake harder, shorter" camp. Gentle braking retains more heat, warps rotors, boils fluid; none of which I'd want happening when I'm coming down a hill at 9000 lbs. EDIT: After pondering this, this method would potentially lead to faster brake wear. Think of taking your DD to a track day. Hard, short braking, but you've chewed up your pads pretty good, as opposed to them lasting a long time doing your daily commute with gentle braking.

If you want to compare to a track day, then you'd have to drive at WOT most/all the way around while dragging the brakes to keep the speed down to a moderate level. This is because a downhill will always give the same amount of "horsepower input" so you'd need to treat the open lapping analogy the same way.

Brake wear, generally speaking, is the rotors primarily do the wearing before the pads are at operating temp, pads primarily wear after they get up to operating temp. Wear goes up exponentially on either part the further you are away from that switchover - ice cold rotors with very aggressive pads is like driving a brake lathe, overheated pads just melts them away at an astonishing rate.

I figure, if you can't smell the brake pads by the time you get to the bottom, you're going fast enough to keep the brakes cool, and wear is being kept to a minimum.

Knurled wrote: Brake wear, generally speaking, is the rotors primarily do the wearing before the pads are at operating temp, pads primarily wear after they get up to operating temp. Wear goes up exponentially on either part the further you are away from that switchover - ice cold rotors with very aggressive pads is like driving a brake lathe, overheated pads just melts them away at an astonishing rate.

Agreed 100%. DD-ing the Jeep with aggressive pads really proved that one to me. When 90% of driving keeps the pads too cold (especially in the winter), rotor wear was a serious problem. As in, 2 sets of front rotors to 1 set of pads kind of bad

In modern vehicles, engine braking is more fuel efficient than iding in neutral. I do not know which technique is better for longevity between compressed or more gradual braking, but I do know that using the brakes less will wear them less and make them last longer...

I hardly ever touch the brakes going uphill or down hill when I'm in northern Arizona/southern Utah with family... gravity and engine braking work quite well. Whenever I'm on the brakes more than usual it's because I'm behind another driver who doesn't know how to go down a mountain....and passing zones are never around at those times it seems...