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Old 08-17-2008, 08:38 PM   #1
Camper Power
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Brakes acting wierd

everytime im traveling at highway speeds and hit the brake, even with light pressure the truck will start pulling either left or right. the pulling goes away after 4 or 5 brake applications, the first pulls pretty hard and get lighter and lighter. it doesnt pull in the same direction all the time and the brakes are just over a year old, with all being drums. im thinkin i need an alignment but im not sure.
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Old 08-17-2008, 09:01 PM   #2
WorkinLonghorn
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Re: Brakes acting wierd

I'd have to agree with your allignment/(front suspension) assesment. If it was only a brake issue it would always pull the same way,in my experience. You need to take a very hard look at all the usual wear points right away.Not only could something break,but during an emergency stop you will spin out instantly losing all control.(Don't ask how I learned this)
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Old 08-17-2008, 10:18 PM   #3
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Re: Brakes acting wierd

by usual wear points do u mean things like ball joints, bushings, grease joints, or brake parts like shoes, return springs, and drums. i dont know much about the maintanence of the front suspention on these trucks exept making sure everything is greased up.

plus ther has been a problem in the past with hitting the brakes speeds around 50-60km/h (30-40mph) and no matter how much pressure on the brakes the truck would start to pulse once you've slowed down a bit, at first i thought it was warped drums but i was told that the brake pedal would pulse instead of the whole truck, and said it might be the road (the roads here can be pretty bad) but i've driven over the same spots at normal speeds but it doesnt make the truck pulse. but the problem disapeared now.
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Old 08-18-2008, 12:18 AM   #4
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Re: Brakes acting wierd

Wouldn't hurt to pull the rear drums and insure your rear axle grease seals are not leaking & the rear brake cylinders are in good shape. If you park on an angle where one side is considerably lower a axle seal will leak enough to cause brake problems.
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Old 08-18-2008, 04:53 AM   #5
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Re: Brakes acting wierd

How often do you drive the truck. I have seen light layers of rust build up and cause the brakes to do funny things until the rust is gone.
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Old 08-18-2008, 05:50 AM   #6
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Re: Brakes acting wierd

brake issue?? pull all drums and look at the important parts to make sure no leaks proper adjustment and operation is the way to start// while its on the jackstands is a perfect time to also access the front suspension for wear while you're lubing the suspension pieces
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Old 08-22-2008, 10:46 PM   #7
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Re: Brakes acting wierd

i have a feeling its the front ones causing problems, i havent got a chance to pull the drums yet, one of these weekends that im not busy and wen ther is nice weather out, its not rust cause the truck is my daily driver. but the truck is starting to shake again wen i abbly the brakes and shakes till i pretty much come to a complete stop.
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Old 08-22-2008, 11:16 PM   #8
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Re: Brakes acting wierd

If you have death wobble you need to take care of that soon! That is not a safe vehical to be driving. Deffinitly take a hard look at all the front end wear parts...
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Old 08-22-2008, 11:30 PM   #9
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Re: Brakes acting wierd

its not a wobble if u mean side to side movment, its an up and down movment wen i aplly lite pressure at normal speeds. but a highway speeds and hit the brakes lightly it will start pulling either left or right, and will pull 4 to 5 brake applications later, what is causing this.
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Old 08-23-2008, 08:53 AM   #10
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Re: Brakes acting wierd

Pulling usually means that a wheel cylinder has leaked fluid onto the shoes which are not breaking or air in one of the front brake lines.
If front suspension, the pull would be pretty much constant without braking or the pulling would not go away as you warm up the brakes. Light rust on the drums can cause this but once you drive it a while, that problem should go away and not come back for quite a while. I would pull the drums and check for leaks. If ok I would then opt for brake bleed, brake line hose check, then suspension check (I would have this done no matter what as old trucks are cool but not worn out ball joints, tie rods, pitman arms, etc.) huck
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Old 08-23-2008, 09:16 AM   #11
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Re: Brakes acting wierd

I've had a similar experiences on some of my vehicles. The wobble part was on a Tahoe with disk brakes. I had warped rotors.

The bouncing part was on a car and it turned out to be an out of round (cheap) tire. Most noticeable at slow speeds. I found out which one by swapping them front to back. Another bouncing problem was on son-in-law's Ranger -had a bad shock.

Now as for your problem, it may be more than one. First you have to determine if it was a sudden change after a parts replacement or a gradual one over a long period of time.

Check for loose tierod ends and/or ball joints and maladjusted or "grabby" brakes. Grabbing brakes can be caused by oil or grime contamination or just defective brake shoes. Also, send the drums in to be turned to make sure there's no problems there.

Make sure all the suspension components are good. By that, I mean that they are not so loose or worn that any slight depression of the brakes will cause the truck to want to go in the direction of whichever brake happens to touch the drum first. Drum brakes are notorious for being persnickety in that area especially if you have power brakes.

Also, make sure that all of the brakes are bled properly -no air/bubbles whatsoever and that the brakes shoes are adjusted properly. Here again, drum brakes are more critical. I adjust until I barely hear or feel them rubbing on the drum-- I do this on all of them.

And last, I'd make sure all your shocks are good so your tires aren't bouncing up and down as you are driving down the road.

Last edited by 68gmsee; 08-23-2008 at 09:17 AM.
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Old 08-23-2008, 09:21 AM   #12
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Re: Brakes acting wierd

One more item I forgot to mention that is critical for proper fluid flow is the rubber brake hoses. They tend to swell on the inside as they get old and you have uneven fluid flow to the brakes. I'd check or replace them even if they look good. It's cheap insurance and sooner or later they will go bad.

There's one on the back above the axle also...
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