Front brake pulling

[Hearse Man]

I am new to this forum but I am buying an 82 K/20 4x4, 6.2, 4sp OD, and 4.10s 130k miles and still has the original paint from a friend of mine. He told me it needs a left front wheel bearing, no problem. But it pulls hard left when you apply the brakes. He thinks it is because of the bearing. I am thinking there is more to it than that. Maybe the bearing has done something to the pads, glazing or excessive wear, causing it to grab harder. I should be getting this truck next week, and I plan on replacing the bearings and brakes. What I need to know is should I plan to replace a caliper too? Or is there anything else that might be causing this? Thx for any info.

[DmaxMaverick]

The bearings won't generally cause problems with the brakes, but the brakes can cause bearing problems. If the bearings get loose enough, they can cause the hub to wobble, which can cause the brakes to drag.

The problem is usually that the brakes drag, for whatever reason, which creates too much heat, and cooks the grease out of the bearings, causing them to fail. Many times in this case, it will toast the hubs as well. If a race has spun or over-sized the hole, it will be nearly impossible to get a new one to seat properly.

It has been my experience with the 82-87's that the calipers should be replaced if any of this occurs. I have rebuilt them with little success after overheating.

If you have to replace the hubs and/or rotors, make sure they are made in the USA by a common brand. If you use those "made in China" or cheap brand replacements, you'll be doing it all over again very soon.

Good luck!

[Brianlar]

I have a friend with a gas puckup that pulls to one side when braking. The problem is the rubber hose from the caliper to the frame swells and causes the caliper to malfunction. When in dought, replace them both.

[Hearse Man]

I replaced the bearings on the front driver's side today but that didn't help with the brake pulling or the bad shaking at 45mph either. Brakes looked good, so did the lines. May have a stuck caliper or something. I got to do something with the front end. It pulls a little right while driving, left while braking, and shakes at 45mph. Anybody got any ideas? There is a little slack in some of the steering components, I greased them, they were dry.

[DmaxMaverick]

Check out your tires. Even if they "balance". If you have a belt separating, it can cause what you describe.

Try switching the front tires with the back, one side at a time. If you get a change in driving characteristics, have the tire shop put them on the balancer, and watch them as they spin. Any variation in diameter or tread tracking could mean the belt has separated.

[More Power]

You might also check to see whether the calipers can slide side to side on the mounting bolts. The calipers should be able to move back and forth across the rotor to compensate for pad wear and any amount of rotor runout/flex.

In the '80's trucks, the calipers are held in place by 2 bolts with rubber seals that hold some amount of grease.

MP

[Hearse Man]

After replacing the driver's side bearings, it still shakes at 35-45mph, but not all the time. I pulled off the pass. side wheel and found that the caliper was stuck. So I soaked it and freed it up. Test drove it and the whole assembly was steaming hot when I got home. The capiler now gets stuck out when I drive, so time for a new caliper. I wonder if a sticking caliper could be causing the shimming I am experiencing?

[madmatt]

do you have a shake, shimmy, or both? A shake is what I describe to customers as more of and up and down vibration most often felt in the floor board or seat. shimmy on the other hand is more a side to side wobbling usually felt more in the steering wheel due to the fact it is caused mainly by a faulty steering componet, although I have seen bent front wheels cause a shimmy. vibrations are generlly tire/ driveline related. either way I suggest as stated above, take it to a REPUTABLE shop, have the tires balanced, lateral run out on the wheels checked to rule out bent wheels, find out what all is loose in the steering, fix thoose items and get an alignment.

[Hearse Man]

Well after replacing the pass. side caliper, it doesn't feel right. It is back to pulling left when I stop. It has only shaken once since the new caliper was installed though. It was shaking so bad that you would think a rim is coming loose. It does have a a little shimmy while driving, I would say it feels like a tire out of round. Gonna rotate all 4 today. When applying the brakes the truck pulsates as it slows down. I don't feel anything in the pedal, but I it feels like the brakes are coming on a little harder then lets up just enough to be noticeable. I am replacing the driver's side caliper today, bleeder screw was rusted to bad and broke of and a new caliper was cheap insurance. I'll let you know how things go later tonight. Thx for the help so far.

[Hearse Man]

I didn't get a chance to replace the caliper, but I did rotate the tires and it rides alot better. Now that it rides better, I think I might have a warped rotor. I'll replace the caliper and check the rotor. I did notice the the front hubs get very warm, is this normal? Not hot enough to steam, but very hot to the touch.

[madmatt]

you usually don't feel a front brake pulsation in the pedal as much as in the steering wheel. any pulsation felt in the pedal is just whats being transfered from the body pulsating and not actually from the brakes themselves since the pulsation sensation cannot be transfered to the pedal via brake fluid. too much other junk in between the pedal and the caliper! be sure when installing your tires you torque them in the correct pattern, otherwise you could continue having rotor problems, or make what you have worse.

[madmatt]

almost forgot... yes heat transfer from the rotors to the hubs can make them extremly hot. even more so during stop and go traffic or while driving around appling the brakes to check them. careful while testing your brakes out or you will damage even brand new rotors if you overheat them or got debris between the hub and rotor mating surface. after installing new pads, they will need to be burnished in. run your vehicle up to 30 mph and gently apply your brakes untill you stop. do this at least 10-15 times, but more won't hurt.

[Hearse Man]

I'll check it out tomorrow and see what's up. In the meantime, you can check out the truck on my webpage. 82 K/20 Diesel, My $1250 wonder

[Hearse Man]

Well, I have it figured out now. I rotated the tires, replaced both calipers and one set of wheel bearings. It doesn't shake or shimmy now. But since I have everything else working properly, I have found that during braking the pass. side rotor has a slight warp to it. So I will have it turned and see if it comes out. I think the combination of the warped rotor, sticking caliper, and out of balance tire all on the same wheel was causing the shaking. Hard to find the problem when it is a combination of three or four problems. Thanks for the help.