Horrific brake noises

Climb under n look. Start there

 

Git. Don't sit here LOL.

Let us know what you see and hear under that thing. We will likely have a opinion when you come out from under there. Maybe some pictures too.

 

I would check that you don't have any leaking wheel seals or that some clown didn't pump a tube of grease into a cam and fill up a brake drum. Oil and grease contaminated linings can grab and chatter.

 

To warp a big truck drum would mean loss of air pressure on the tire attached to it. Im not current on modern rims but warping a big drum would set a viberation in your entire rig.

You wont have pulsastion on your service brake because you are working a supply tank that is between you and potentially the source of back flow air strong enough to make your brake pedal pulse. There is nothing there. That I can think of. That tank will dissappate and lower the pressure of pulses when it is reached. And you adding air means its going out through the pulses anyway. This is not hydraulic where a car you can feel the problem. Just a gentle reminder.

Again your truck will shake and shiver if there is a big enough issue with your braking. A walk around after such a stop will reveal the hotter wheel than the rest. Don't touch the wheels, just be close enough to estimate by your hand feel the heat.

I have a couple other ideas but those tire boys will have to be really incompetant or truly stupid to introduce additional problems. balance would be one.

 

Wow ok do you feel safe?

If not don't drive it.

Pedal pulsation in an air brake system. Need to go back and learn how air brakes work, that's scary.

 

This one kept me up tonight. I cannot recall a incident ever that the pedal pulsed. But I sure as hell remember all sorts of brake related problems... interesting ones too. Such as the rubber plate that confines air inside the one half of the chamber not used by the other half with a spring for parking and emergency. I once had a truck that ate it away with sludge in a tank with no air cleaner. (Not draining each night... ) and it ate the rubber away enough to present this...

Slow from 60 mph for the jones falls ramp off 695 E to 83 south and it's a 30 mph ramp. Milk tanker means 20 until past halfway mark then add power for the short 5% upgrade. Well... coming off 60 with brake application caused both primary and secondary to lose and bleed down to 40 pounds and dropping.

Still at 35 and coming in the first third of the ramp. Fixing to completely shut down the entire thing with a stalled truck and no air. Ugh. So I nursed it along. We finally solved the root cause of teh problem. But it was INTERESTING. Not in any of the books Ive been taught in school oh no... no.. Did I make it? Yes. at 40 mph waiting for the compressor to get ahead of the leak. back to something like 65 pounds to get that infernal horn to shut up. (Low air alarm...)

 

My experience with "techs" is they can screw up as much as they fix!! A tire man would have no reason to check anything about your brakes, unless they pulled a wheel off and were looking at a cracked drum.

Missing spring, loose rivets, so the lining is loose on the shoe, could be S cams so dry and totally wore out, glazed shoes.

Crawl under it and if one wheel end looks different then the others.