I need help I got a 2006 Peter built dump truck that is pulling hard to the left when applying brakes and the more you apply the brakes the worse it gets the front end has new tires, s cams, new bearings for the s cams and seals, new brake pads, drums, slack adjusters, cans, new pressure regulator for both sides and front one under the truck I have came to a stop cause I have no idea what to do now
Welcome to the Forums! Unfortunately I am no mechanic much less a truck mechanic however we do have several knowledgeable members who can help you out. Good Luck!
Pulls left = contamination on the right . If you have oil bath bearings and the inner seal goes, it can coat the shoes and it may not find it's way out to see it.
Check the air lines for kinks and sharp bends, verify correct free stroke on slack adjusters
Everything is clean and dry and no kinks or hard bends anywhere
Most of the time when I have brake issues, pulling to one side or the other, the problem isn't in the steer, its back in the tandems.
What has been wrong with the tandems to make it pull to one side or another
Check the slack adjuster adjustment, I really hate auto adjusters
Could be adjustment, could be a brake can, could be air lines, could be a spring gone- could be a lot of things. Get down under it with a flashlight and get someone to push the brakes - and see what the brake shoes are doing.
All brakes are adjusted to where they need to be no broken springs but a maxi can is bent towards the tire on the driver side on the front drive axle
The way to check if a rear is pulling-disconnect and plug air lines to front steer brakes and drive it. While your at it put a gauge to each air line to front brakes watching air app gauge on dash with 15 psi applied to see if both are the same. Is one drum hotter than the other? have you checked to see if shoes retract. Did you clean the area of pilot on hub so drum fits flush, those tangs corrode and drum won't set flush. Are you sure you have no air leaks from side to side? Are the drums the same from side to side depth wise/OEM. Lastly use a tape and measure the stroke at 30 psi app. Did the S-cam spin free once installed. And is the shoe material the same from side to side?
One other question-were these reman shoes with old shoe webs or were those new shoe webs. About 2 out of every 12 reman steer and 2 out of 30 reman drive brake shoes the webs are distorted. Which cause a poor arc to the shoe or the anchor pin end is not aligned allowing shoe to rest at a slight angle and makes for lousy shoe/drum contact.
Maybe s-cams aren't matched? We had a dump truck that would lock up one corner empty on gravel. Then someone suggested checking the s cam profile and it turned out that corner had the wrong cam. Problem solved.
Hold your foot on the brake for about 40 psi application pressure. Watch for pressure bleed off, or have someone check the front brake lines for leaks. I've had front brake lines that looked great, but leaked.
2006 should have come with Q-Plus style shoe, If it had a non Q-Plus S-cam wouldn't be able to install drum.