Pulling when brakes are applied.
Thread Starter
|
Senior User
Joined: Jun 2003
Posts: 152
Likes: 0
Pulling when brakes are applied.
I have a '72 F100 with the 4 wheel manual drum brakes.... I have been daily driving it for a couple weeks now and noticed that when the brakes are applied abruptly the truck veers to the left. The first time it did it, it was quite a surprise as it veered right into oncoming traffic.
I am guessing that one of the front drums are adjusted farther out than the other, does that sound right? Would it be the left or the right?
Thanks for any help
I am guessing that one of the front drums are adjusted farther out than the other, does that sound right? Would it be the left or the right?
Thanks for any help
Post Fiend
Joined: Jun 2003
Posts: 8,209
Likes: 12
From: Black Hills of SD
Pulling when brakes are applied.
You should just tear it down and have a look, it could be alot of things, leaking fluid on the brake shoes will make them grab. One drum turned more than the other resulting in a difference in the total swept area. Even worn front steering and suspension parts can cause the problem. Not to mention a froze or non working adjuster on one side.
Lead Driver
Joined: Jan 2003
Posts: 9,893
Likes: 12
From: Ohio
Pulling when brakes are applied.
Sounds like a "wet" brake on the right side....causing it to NOT grab. One of two things. Either adjust it up and see if that helps or see if it is wet around bottom of backing plate from wheel cylinder is leaking(causing wet brakes and NO friction to stop).
Larry
Larry
Senior User
Joined: Jun 2003
Posts: 188
Likes: 0
From: Wesley Chapel, FLA
Pulling when brakes are applied.
Those things mentioned could well be the problem but another thing to remember is your self adjusting brakes will only self adjust when the brakes are applied in reverse. If this doesn't happen much in the normal course of your driving they could be out of adjustment and you'll have to do it on purpose. Find a smooth road or parking lot, get going pretty good in reverse and jam on the brakes. Do this several times. It helps to be going backwards down hill. You can jam them several times before you have to get going again. It's the act of applying the brakes that does it, not holding the pedal down after hitting it. When you're done you may notice you've got better "pedal".
That's how you adjust your brakes when everything is in good working order. If that doesn't work you'll have to go in, have a look and get things right. Makes sure your adjusters are in good condition with anti-seize compound on them where needed so they stay free. The system does work but it's easy for it not to.
The brake that is working best is on the side it's pulling to. One side wants to stop, the other side wants to keep going.
That's how you adjust your brakes when everything is in good working order. If that doesn't work you'll have to go in, have a look and get things right. Makes sure your adjusters are in good condition with anti-seize compound on them where needed so they stay free. The system does work but it's easy for it not to.
The brake that is working best is on the side it's pulling to. One side wants to stop, the other side wants to keep going.
Post Fiend
Joined: Jun 2003
Posts: 8,209
Likes: 12
From: Black Hills of SD
Pulling when brakes are applied.
If you have a bad leak then that side will obviously have less friction, but a brake lining that is just a little damp WILL grab, and even more so if it is grease leaking on the lining as in a rear brake. It is an old truck, pull the drums and inspect your brake system. If you haven't looked in there before then you need to. And while you have the drums off take them over and get them measured. I have seen plenty of these over the years that have been turned and/or worn way beyond the servicable limits. I have seen them where the adjuster works fine but it runs the threaded part all the way out and it falls apart inside. Do a thorough inspection, for safetys sake.
Thread Starter
|
Senior User
Joined: Jun 2003
Posts: 152
Likes: 0
Pulling when brakes are applied.
I'll try adjusting them by braking in reverse. I checked the left front and right rear brakes about a month ago and they were all practically brand new and the drums were thick... There's no wheel cyls leaking as far as I know. The truck has had a complete mechanical overhaul not long ago.
To be honest my experience with manual drums is pretty limited, all the drum vehicles I have owned have been converted to disc!
I'll see if it comes back and if so I'll look more in depth - thanks.
To be honest my experience with manual drums is pretty limited, all the drum vehicles I have owned have been converted to disc!
I'll see if it comes back and if so I'll look more in depth - thanks.
