New brakes...smoking

[jasonsherman]

I just replaced all 4 drums and brake assemblies for a trip to CO. There's a 6 mile downhill with about 6% grade on I70 after the Eisenhower Tunnel. After about 4 miles of braking , I could see smoke coming out of the wheels.

Is this normal with new brakes?

If not, what's the problem and should I be concerned?


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[Protagonist]

Originally Posted by jasonsherman

I just replaced all 4 drums and brake assemblies for a trip to CO. There's a 6 mile downhill with about 6% grade on I70 after the Eisenhower Tunnel. After about 4 miles of braking , I could see smoke coming out of the wheels.

Is this normal with new brakes?

If not, what's the problem and should I be concerned?

Meaning no offense, but it appears to me the problem is that you spent too much time with your foot on the brake to control your speed, and not enough time downshifting to use engine compression to control your speed. Anybody's brakes would be smoking after four miles of braking on a downhill grade!

I think you may be ready for another brake replacement after that. Maybe drum replacement as well if they warped from the heat.

[ROBERTSUNRUS]

Hi, while going down hill I always down shift and rarely even have to use my brakes; When I do, it's just for a few seconds at a time. All of my brakes were replaced after ten years and many tens of thousands of miles, and they still weren't worn out. Down shifting is done whether towing or not.

[A W Warn]

Originally Posted by jasonsherman

I just replaced all 4 drums and brake assemblies for a trip to CO. There's a 6 mile downhill with about 6% grade on I70 after the Eisenhower Tunnel. After about 4 miles of braking , I could see smoke coming out of the wheels.

Is this normal with new brakes?

If not, what's the problem and should I be concerned?


Sent from my iPhone using Airstream Forums

Overheating the brakes can cause them to be glazed, shiny and slick. If this has happened the brakes will not create the proper amount of friction to function properly. It is possible to rough them up a bit with sandpaper. If there is cracking or warping, replace what is needed. Get them checked out before doing another long grade.

When at the top of a long steep grade, I normally shift down to second or third gear (6 speed) at the top of the grade and slow down as much as possible. There's usually a posted speed limit for the big trucks, that's what I try to do. Saves the brakes and it's a lot safer.

[RangerJay]

A couple of things not yet mentioned that seem IMHO to be important:

• make sure your brake controller is set up properly - you don't want the trailer trying to do the job of braking both the trailer and the truck.
• enter a posted downhill grade with an abundance of caution - at least till you know what you are dealing with - and as already mentioned gear down so the engine helps keep your speed in check.
• on a long, extended grade determine a comfortable speed that you do not want to exceed - (I'm going to suggest that it should be less then the posted limit) - if your speed reaches your own limit then brake fairly firmly to slow yourself down - then release the brake till you reach your own limit again - the key point here is you do not want to ride the brake - also note that the more often you have to use the brakes suggests you might want to lower your own upper limit - and perhaps gear down some more.

And yes - after an event where your brakes were smoking - it would be a good idea to check them out then make sure they are adjusted correctly.

Good Luck


Jay

[GCinSC2]

A favorite tool of mine for diagnosing heat issues, IR Temp gun. Helps you find the heat.

Also used it cooking one time making pancakes, cheated and used it to check griddle temp. Worked.

[jasonsherman]

Thanks for all the help. I'll keep you posted.


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[Action]

Rarely does new brake lining on a brake shoe exactly conforms to a drum until it has been used a bit. The trick is not to have heavy brake use until the shoes conform to that drum. In that period of newness, full brake shoe contact does not occur. Therefore the effectiveness of the brakes is not as good after some use. Appling more brake pressure to the shoes will generate more heat than the shoe/drum can shed, creating smoke and possible hard spots on the drum. With hard spots the braking will be uneven as that hard spot come in contact and goes out of contact with the shoe. A hardened brake drum surface is not a good friction surface for braking.

>>>>>>>>>>>>>Action

[wulfraat]

I do that drive all the time... that is not normal. sounds like you were holding your breaks for too long. It's better to downshift and then brake (harder) periodically rather than break constantly, which generates more heat.

Pads are likely glazed, I'd replace.

[joqin]

meaning no offense,but all yall from colo. who "drive that all the time" should consider that the rest of us don't! That stretch of road is one of the top 10 scariest drives with a trailer. I've heard truckers on the CB ( fron the east coast) who won't drive past denver because of that road. You can get up to 85 mph coasting on some of downhill sections. I've seen more OTR semis pulled over and smokin on parts of that route than any other, and that includes the bighorns and north yellowstone and the back way into palm springs. just my opinion,driving a school bus on MN ice for 26 yrs.
joe the bus driver

[nrgtrakr]

Even when not towing, I stay geared down on either side of Eisenhower Tunnel and a few other places in Colorado and I grew up driving here.