Brake life

[Gumpy]

Hello all,
I've appreciated the knowledge on this forum.
I recently acquired a '85 6.9 C6 E350 15 pass van.

I keep several hundred pounds of stuff in the van at all times but usually only have 3 people in there. I frequently drive 3 hours, 100 miles mountainous, 50 miles mostly flat, all highway; speed limits 40-65mph. This makes up 90% of the miles on the van since I bought it. I use engine braking extensively on the first 50 miles to avoid excessive brake use.

I have 2 questions:
1. I'm beginning to think that I'll be replacing the rear brakes often. The rotors were $90 each and the pads were $70. With the 20% off coupon those parts came out to $200. On rockauto the parts are close to $125 + shipping. How often should I expect to replace these parts? The cost is seeming prohibitive. Do all heavy trucks have this problem of burning through brakes?

2. One of the rear brakes seems to be loosening up. I think it's happened twice now. I adjusted the brakes the first time. I haven't gotten around to pulling the hub off yet to see what's going on. This makes the van pull to one side when braking. Any thoughts on what is happening. The auto adjusting levers are not installed b/c I had a parts fiasco.

I recently replaced rear rotors, cylinders, shoes, other hardware, and master brake cylinder.

 

[franklin2]

You have rear disc brakes or rear drum brakes? You said you replaced the rotors, so that would be disc brakes. But then you said you replaced the cylinders, which would be a drum brake. Just trying to be clear on what you are working on.

 

[Gumpy]

Yes drums. I was trying to get my terminology correct. Sorry

 

[franklin2]

The automatic adjusters on these units never seem to work correctly. Some people seem to have it down and can make them work, but I have never been able to. I just disconnect the cable and just manually adjust the brakes about every other oil change. The auto adjuster can sometimes over tighten the brakes, and then sometimes they don't seem to work at all.

If everything is new, I would suspect the adjusters. The drums themselves should last through many brake service intervals. They do eventually wear out, but it takes a long time unless you accidentally run the shoes down to the rivets and they dig into the drums. If they start getting a small lip from wear, I don't worry about it till it gets so bad that you have to loosen the shoes a lot to get the drums off.

Since you have a 1985, I suspect you have a dana type rearend? Do you have to pull the hubs to work on the brakes (on the dana you usually do). That is pretty aggravating with those type rearends.

 

[catbird7]

The wear components are pads and shoes. If you're routinely replacing other components, there are other issues that need to be corrected. For example if you're replacing pads and rotors, you likely have a caliper hanging up. Rear drums that hang up (pull to one side) are, typically the result of contamination on the shoe and usually a leaky axel seal, or wheel cylinder. It's also important to monitor rear tire wear when attempting to use the engine / gearing to assist braking. I think you'll quickly realize the price of tires far exceeds a set of brake shoes. Modifying driving habits is probably best advice, when it's possible plan far in advance for each stop.

 

[IDIBRONCO]

Since you have a 1985, I suspect you have a dana type rearend?

My 1985 has a Sterling rear end. I sure would hate to have to pull the hub to work on the rear brakes. Thankfully, I've only run across one of those.

 

[Gumpy]

I accidentally ran 3 miles home with the parking brake on soon after I got the van... Thus the brake job. I have a Dana axle. It took me a while to figure out how to get to the brakes. The oil runs out and then you have to refill the oil. etc etc. It is a pain.

There are no automatic adjusting levers in the drums right now. Are they necessary to keep the adjusters from loosening? I've had my pedal start sinking to the floor twice since the brake job and each time I re-adjusted the rear brakes. I've only driven maybe 5000 miles total since I've had the van. The second time the drivers side brake needed more adjusting than the passenger side. Then the van started pulling to the drivers side after a little while. I'll consider the seals when I pull the brakes. I didn't realize a leaking wheel seal could lube the brakes in some vehicles.

If the drums last many shoe replacements that will work for me. They're much cheaper than the drums.

 

[Big Bart]

Gumpy,

Some other thoughts on shoes wearing out quickly. (Keep in mind you said you are doing a lot of braking in the moutains and you keep a fair about of weight in your van.) So you would see the need for brakes sooner than many on this site. But if like every 15K miles there is a need for rear drum shoes that would seem excessive to me. (Unless you ride your brakes or keep braking fast and hard.)

Some things to note.

1) Cheap brake parts wear out faster period. So stay with good brands like DFC (Dynamic Friction), Bosch, Motorcraft, A/C delco, and such. When doing front or rear disc brake pads, always go semi-metalic or ceramic. When doing shoes also try for semi-metalic. Cheap ones will wear out much faster and not stop as well. So on Rock Auto, don't buy the stuff in the "Economy" section, rather the "Daily Driver" or "Heavy Duty" section.
2) I suggest you always do the set. So shoes and drums and pads and rotors. If your drums are grooved and you do not replace them. They may just eat up your shoes in a hurry. Sounds like last time you did the drums too so hats off to you.
3) You mentioned that you have some hardward missing in the rear end. That needs to be addressed ASAP and could be part of your issue. Remember that your auto brake adjuster mechanism is what keeps your brake adjuster from free spinning. So no brake adjuster in place, your adjuster could be backing itself off causing that drum set not to brake well. Making your truck pull to one side. So fix this issue ASAP, its a safety issue.
4) Also check your rear axle bearings, if they are worn or loose they could be causing the drum to cant and the shows to wear out quickly. (You mention you travel with a lot of weight all the time.) Jack up each side wigggle the tire at 12 and 6 and 3 and 9. If you feel much more than a little movement this could be adding to the wear. See if your shoes are wearing evenly.
5) Many have stated that often the e-brake does not fully release on these older Fords. (Wearing down the shoes and drums, then causing the brakes to be less effective. Some are putting on a spring where the cab e-brake cable meets the rear axle cables to pull it back in order to fully release.
6) You have air in the front brake circuit, so the rears apply more pressure. Try bleeding the brakes.
7) Some other situations that are less common but could be in play.
a) Your proportioning valve is not working correctly. (To much pressure going to the rear brakes.)
b) One or more lines have a blockage. (Such as the rubber hose between the truck and rear axle is ballooning inside.) So the high pressure of the fluid from the master cylinder pushes its way through a restriction, but the brake springs are not able to add enough pressure to return to norm. So they get stuck partially on.
c) Your master is starting to wear out. So the front brakes get less pressure than the rears. I do not recall how our brake lines run. Typically one vehicles one of the pistons in the master cylinder serves the front brakes and the other the rear. If the master is wearing out, it could be the rear brakes are doing more braking because the front are not getting the right amount of pressure.

Your brakes are adjusting the wrong way and becoming loose.

1) Just confirm that it is the adjuster turning backwards (Loosening the brake drums.) by pulling off the brake drum. If you have one side dragging or wearing out faster it could be that, not the adjuster loosened up. So if the shoe has a lot of wear then maybe it is not loosening, its draging.
2) Eitherway I would buy a replacement drum brake kit that has the adjusters, cable, springs, clips, etc. And put that all back in place as it should be. Here is one from Rock Auto.

https://www.rockauto.com/en/moreinfo.php?pk=3056799&cc=1116672&jsn=507

3) Lastly as I recall another issue is that you have to have the correct adjuster on the correct side and have it facing in the right direction. (One tightens going clockwise and the other going counter clockwise. Not sure if our trucks use that style.)
a) I want to say last time I did drum brakes I realized that one side adjusts out clockwise and the other counter clockwise. So if you reverse your system will loosen up your brakes not adjust them tighter. I think many folks would think they are the same and can be used on either side. But I do not believe that is always true.
b) If you put the adjuster in backwards, the auto adjuster lever will not hit the adjustment star and adjust the brakes properly.
c) I always suggest when doing your brakes you do one side at a time. That way you do not reverse hardware and you always have the other side to look back to if you forget how something came off.

Let us know what you find and send some pics. Sometimes we can pick up on things from the pics like missing hardware, leaky wheel cylinders, leaky axle seals, etc.

 

[IDIBRONCO]

My 1985 has a Sterling rear end. I sure would hate to have to pull the hub to work on the rear brakes. Thankfully, I've only run across one of those.

Just to be clear here. When I posted this, I had forgotten that the OP has a van. I was talking about my truck. The vans seemed to lag a little behind the trucks as far as advances in technology went.

 

[franklin2]

3) You mentioned that you have some hardward missing in the rear end. That needs to be addressed ASAP and could be part of your issue. Remember that your auto brake adjuster mechanism is what keeps your brake adjuster from free spinning. So no brake adjuster in place, your adjuster could be backing itself off causing that drum set not to brake well. Making your truck pull to one side. So fix this issue ASAP, its a safety issue.

You can see from the pictures below, if the auto adjust cable is removed and nothing else, that it will disable the auto adjuster and still let the brakes work properly. The little adjuster arm does not have to be removed if the cable is removed.

 

[franklin2]

Gumpy,

5) Many have stated that often the e-brake does not fully release on these older Fords. (Wearing down the shoes and drums, then causing the brakes to be less effective. Some are putting on a spring where the cab e-brake cable meets the rear axle cables to pull it back in order to fully release.

A spring like that is factory.

You must be registered for see images attach

 

[Big Bart]

You can see from the pictures below, if the auto adjust cable is removed and nothing else, that it will disable the auto adjuster and still let the brakes work properly. The little adjuster arm does not have to be removed if the cable is removed.

Franklin,

I wish I had a pic of your brakes with the drum off so I could see yours in particular. See what is holding the adjustment leaver up against the adjustment screw and star. Eitherway I will take your word for it. I prefer to put things back stock, but you said yours was having issues thus the delete.

I have done several rear drum brakes over the years, it always seemed it was the adjust cable that pulled up on the adjuster lever and locked/held it to the star gear of the adjuster screw. (Otherwise it basically dangled.) That way the star gear would not free spin. (Loosen or tighten accidently.) I see an "adjusting lever return spring" in your PDF, perhaps that is what is keeping the adjuster tight up against the star in this case. Thus to your point does not require the adjustment cable. If not, leaving it to spin freely is not advisable.

Do your PDF's show a different part number for your adjusting screw and socket or adjustment arm based on side? On my son's Galaxie I recall the left and right sides used a different thread on the adjustment screw. One clockwise and one counter clockwise. Curious if these trucks did too.

 

[Gumpy]

The left and right adjusters are different. I bought all new brake parts but I did not have the auto adjusting levers to put in. I'll carefully make sure I understand the system and get things installed properly when I pull it apart.

Thank you for the detailed list of possibilities. I'll think about those as I work on it.

 

[TNBrett]

I've had my pedal start sinking to the floor twice since the brake job and each time I re-adjusted the rear brakes. I've only driven maybe 5000 miles total since I've had the van. The second time the drivers side brake needed more adjusting than the passenger side. Then the van started pulling to the drivers side after a little while. I'll consider the seals when I pull the brakes. I didn't realize a leaking wheel seal could lube the brakes in some vehicles.

I think you may have more going on then brakes simply not being adjusted correctly. Perhaps you should try bleeding the brakes out again. I don’t think your brakes being out of adjustment would let the pedal drop to the floor. It may be time for a new master cylinder. Don’t jump to that conclusion just yet though. Sounds to me like you need to go through and check everything again. FWIW a leaking axle seal on one side can definitely make it pull to one side.


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[Gumpy]

I was reading somewhere on this forum that the rear brakes are what determine the pedal travel. I don't understand that but after I adjust the rear brakes the pedal travel returns to normal.

I replaced the master cylinder recently. It's always possible it's a bad one.