AZ Mountain Driving---How!

[Rich-n-Linda]

I'm not saying brake fires don't happen. Misuse them and a fire is a definite possibilty.

My comment was directed at the issue of not taking your foot off the brake after you stop. THAT'S the "old wives tale."


Rich & Linda

[Raining Star]

Originally Posted by Rich-n-Linda

I'm not saying brake fires don't happen. Misuse them and a fire is a definite possibilty.

My comment was directed at the issue of not taking your foot off the brake after you stop. THAT'S the "old wives tale."


Rich & Linda

Got it, thanks for clarifying. That's very possible, I have no knowledge one way or the other about keeping your foot on the brake. I've never came across anything like it. My job forces me to keep up on all kinds of safety issues and nothing about that has ever came up.

Having said that though, I will say that some of the officially published information about bus safety has been known to change over the years because much of it is from "common sense" suggestions, rather than hard data and gets proven wrong from time to time. I'd think if there was the slightest evidence for holding your foot on hot brakes it would be standard information in the reams of published safety info that we get.

So I'd say you're safe in assuming that much is indeed an old wives tale. But then again, what do you loose by doing it, if for some reason you overheat your brakes to the fade point? I think I would do it just because it can't hurt anything, and what the heck, it might actually do some good! Sounds unlikely though.

[PushedAround]

Originally Posted by Raining Star

But then again, what do you loose by doing it, if for some reason you overheat your brakes to the fade point? I think I would do it just because it can't hurt anything, and what the heck, it might actually do some good! Sounds unlikely though.

If the principles are anything like race cars, and I suspect that they are, you absolutely do not want to keep the brakes clamped to the drums or rotors. At best it will cause massive material transfer from the pads to the drums and you will have to get them all resurfaced. Worst case it will cause them to distort so badly that you will have to replace everything. Best to get off of them ASAP and let them cool. If you get pulsing or reduced performance then they will need to be serviced.

[DMTTRANSPORT]

Originally Posted by GKU

Hello everyone,
I am new to this forum and new to the world of Motor Homes.

I have a Tiffin Red 38QRA 340-Cummings and 3500 Allison-towing Jeep Wrangler

I am from FL so I have little mountain driving experience.

Is my coach going to be able to handle grades of 6-7% on I-40?

When approaching a grade should I have the Trans in standard or economy mode? The going up what should my actions be. I think that I am a little more concerned going up then coming down.

Any help would be appreciated.....Thanks

GKU

The grades on I 40 in AZ are short and sweet, be more concerned with the condition of the road....

[DMTTRANSPORT]

Originally Posted by plasma800

I can tell you this, I-40 SUCKS, and it especially sucks between Kingman and California (although kingman is a lovely place!)

I'm not sure which direction you're going, but the mountain pass near flagstaff is like a rollercoaster with narrow lanes against a wall of rock, twists, blind curves at the bottoms of grades, and pot holes the size of your grandmothers house, surrounded by 18 wheelers who think it's fun to do at 90MPH, and especially think it's fun to overtake you in a blind curve.... for about 22 miles...

IF you decide to drive on this incredibly poorly maintained road, be on the ready for how your exhaust brake works. And just get your coach down to say 45 and flip it on, it will hold you back no problem. Matter of fact, it will slow you down to 25 without even touching the brake... but be ready, cause everyone is gonna hate you for it

Ya wanna have real fun?? Do it at night

Better route, take 1-10 if you can. It's flat, wide, and lovely!

Really, your perspective of I 40?? The surface sucks but rollin, sharp curves, oh and the Trucker part 90? right!

[Mekanic]

Originally Posted by JEEPOHOLIC

Just in case you do over heat your service breaks, when you get stoped, dont take your foot off of the breaks, keep those pads pressed tight to the break rotors, or drums, letting oxygen in between the pads and the rotors can cause a break fire

I this is a bad idea for hydraulic brakes. This just transfer more heat to the caliper from the rotor. And of course the caliper is the only brake part at the wheel that contains the brake fluid.

Originally Posted by Raining Star

Got it, thanks for clarifying. That's very possible, I have no knowledge one way or the other about keeping your foot on the brake. I've never came across anything like it. My job forces me to keep up on all kinds of safety issues and nothing about that has ever came up.

Having said that though, I will say that some of the officially published information about bus safety has been known to change over the years because much of it is from "common sense" suggestions, rather than hard data and gets proven wrong from time to time. I'd think if there was the slightest evidence for holding your foot on hot brakes it would be standard information in the reams of published safety info that we get.

So I'd say you're safe in assuming that much is indeed an old wives tale. But then again, what do you loose by doing it, if for some reason you overheat your brakes to the fade point? I think I would do it just because it can't hurt anything, and what the heck, it might actually do some good! Sounds unlikely though.

It can do harm I believe.
You will just prolong your brake cooling on most vehicles.

The air brakes (Drum brakes) on a large OTR truck are Very different from most other modern brakes.
on drum brakes the linings surface area is much closer to the surface area size of the drums. and on drums the linings are quite a ways from any fluid.

On disc brakes it is completely different. The pads are in the caliper right next to the piston and fluid.


99.99% of brake fires are NOT the brakes. its the axle gear lube, or wheel bearing grease that has leaked from a seal that has melted, or even the tire its self has gotten to point it goes up.
funny thing a about a tire on fire is that they will almost only light up once the vehicle has been parked and no longer has any air flow across it.

[DonDee]

My SW had evidence of a fire noticed when the rear brakes/seals etc. were replaced when a seal blew. The gear lube ignited but self extinguished.

[jimbo2013]

just got off I-40 this afternoon from Dallas, I-40 was learning experience, wish I read this before.

Tried eco mode, mistake temp went up lugging hills, hit 220 about 100 yards from top of one, coasted down at 65, 70 75, that cooled it down to 190 fast.

I found going under 60 was harder than 62-65, hitting 5th at the beginning of the hill helped a lot.

But today to switch 5th to 6th for the last 300 miles never went over 209 and wasn't for long.

I was also fighting a really strong cross wind 30-50 knots at times, I assume a strong wind takes more HP to overcome also.

Having a Silver Leaf was a great investment......

headed north to Yellowstone in two weeks I guess I'll see some real grades.

[azpete]

east bound 1-40 is being paved west of flagstaff on the hill. its going to be great when they finish. lots of traffic there backed up. patience is a virtue.
the hill on `1-17 is the worst of all the grades on az interstates. just get behind a truck, and take your time going up. lots of 4 wheelers trying to see how fast they can make the grade. this hill, up and down, accounts for a lot of the wrecks in az.
going down isnt bad if you just downshift and use the engine brake. i lost a good friend when his truck left the road at bumblebee area. there is not much forgiveness for mistakes there.