HighcountryMike's parking brake project

[boywonder]

I'm busting this off from this thread ......

https://www.sportsmobileforum.com/fo...y-32305-2.html

So Mike brought his 2003 SMB EB 7.3 by yesterday to determine why the e-brake was non functional.......

The history: .... a few years ago the dealer did the rear brakes and the parking brake hasn't worked since then.

I climbed under the van while Mike cycled the e-brake pedal...and confirmed that all the cables were functional.

We then pulled the rear rotors off and spun the star adjusters..

Driver's side was a little slack tightened up shoes until drum/rotor would just slip on then backed off the star adjuster a click or two.

Passenger side was very snug..struggled to get the rotor off from shoe drag....once removed the shoes were somewhat glazed. Obviously that side was adjusted too tight with e-brake shoe drag causing the glazing.

I sanded the glazing off and loosened the star adjuster a few clicks to get the rotor to just slip on and off without drag, then did a test drive.

We coasted down a mild downgrade at slow speed and applied the e-brake a few times to bed the shoes in a little, and repeated this a couple of times in reverse.

The e-brake certainly grabs better, but won't hold then van on a steep hill.

For a sanity check we did the same exercise in my 2008 E-350 and had no problem locking up the rear wheels when coasting slow and applying the e-brake on a steep hill.....and yes we understand that the 2008+ brakes are larger.....and Mikes van is at least 1000 lbs heavier than mine.

I had a similar experience with my Honda Element when doing the rear brakes/replacing rotors without changing the parking brake shoes. My driveway is sloped and the e-brake wouldn't hold the car in the driveway..annoying. I lived with this for a couple of years and then bought new rotors/pads and parking brake shoes......after a quick slow speed bed-in problem solved.

......so Mike is ordering rotors, pads and e-brake shoes and we'll change everything (his rear brakes have maybe 40% pad left so not the end of the world).

If that doesn't work perhaps the brake cable is stretched, although I've never replaced one on any vehicle that I've ever owned. It does seem to go quite far to the floor even with the shoes snugged up.

[posplayr]

Originally Posted by boywonder

mine.

......so Mike is ordering rotors, pads and e-brake shoes and we'll change everything (his rear brakes have maybe 40% pad left so not the end of the world).

If that doesn't work perhaps the brake cable is stretched, although I've never replaced one on any vehicle that I've ever owned. It does seem to go quite far to the floor even with the shoes snugged up.

I'm really glad you started this thread. I have a full set of disks, pads, and brake shoes already "in inventory" (2000 E-350 XLT "Drum in Hat" rear Ebrakes), but I'm somewhat concerned that that will not help the Ebrake situation.

After reading your summary, I did a review of my 2000MY FSM (starting 206-05-2) Under Diagnosis and Testing (206-05-08) it states:
"Check the parking brake by depressing the parking brake control pedal. The parking brake must be fully set by applying pressure to the pedal before it reaches a mechanical stop. If not as specified, install new parking brake cables as necessary."

It seems there was never an intent to adjust the rear Ebrake shoes to accommodate for stretched control cables. At best shoe adjustment can account for stretch differential between the left and right sides of the Ebrakes.

That being the case I looked at putting a capability to adjust the intermediate cable (the 17" cable with clips at both ends). See the attached drawing which can be constructed from the Amazon parts below.


https://www.amazon.com/Suiwotin-Turn...01&sr=1-4&th=1

https://www.amazon.com/gp/product/B0...YL6KEKEDV&th=1

[bigriver]

If that works it's an elegant, doable solution to very common problem. Please update this post with your results. Good work posplayr.

[arctictraveller]

I’ve had the exact same issue for years until I investigated how much contact area the shoes had on the drum (hat on disc style). In the distant past, brake shoes were ground or “arced” to the same radius as the drum on a machine found in most well equipped shops. Doing this was especially important, when the brake drums were re-machined to a larger inside diameter, but this is rarely done these days. With the advent of disc brakes, this equipment faded away. Brake shoes were then sold as being “pre-arched” Anyway, on my last brake job I placed the shoes into the drum and using feeler gauges I discovered there were large areas where the shoes didn’t touch the drum reducing the contact area a lot. By using a sharpy I marked up the shoes, pressed them into the drum and rotated them, the high spots were worn away and the low spots still had ink showing. By grinding and filing the high spots off I finally got around 70 to 80% contact, after which the parking brake actually works reasonably well. It’s a Time consuming pain in the ass, but worth it. I wondered, if alternatively, I couldn’t have taken the drum to the auto parts store and test fitted several different boxes of shoes to see if any were closer to the desired radius. So now, I have a parking brake that actually holds on a hill for the first time since I’ve owned the van.

[vandiesel]

I too have this issue and am watching this closely.

[Ben10281]

Originally Posted by arctictraveller

In the distant past, brake shoes were ground or “arced” to the same radius as the drum on a machine found in most well equipped shops.

This is interesting, I replaced my parking brake shoes last year, and my parking brake works waaay better now. However, some days when I press on the pedal it barely pushes in before grabbing tight, and other days it will push all the way to the floor. The parking brake is tight in both scenarios, but I wonder if the differing pedal positions is due to a misfitting brake shoe!

[BrianW]

Originally Posted by boywonder

I'm busting this off from this thread ......

https://www.sportsmobileforum.com/fo...y-32305-2.html

For a sanity check we did the same exercise in my 2008 E-350 and had no problem locking up the rear wheels when coasting slow and applying the e-brake on a steep hill.....and yes we understand that the 2008+ brakes are larger.....and Mikes van is at least 1000 lbs heavier than mine.

Are the 2008+ REAR brakes larger than previous years? I thought it was only the front brakes that are larger?

[posplayr]

Originally Posted by bigriver

If that works it's an elegant, doable solution to very common problem. Please update this post with your results. Good work posplayr.

Parts are ordered.

[posplayr]

Originally Posted by BrianW

Are the 2008+ REAR brakes larger than previous years? I thought it was only the front brakes that are larger?

Apparently a different part number for 08 and above

https://www.ebay.com/itm/13182648962...3ABFBMjLmZib5j

Fits these vehicles:
2003-07 Ford E250 Rear Brake Pad & Rotor Kit
1999-02 Ford E250 Econoline Rear Brake Pad & Rotor Kit
2003-05 Ford E350 Club Wagon with Single Rear Wheels (SRW) Rear Brake Pad & Rotor Kit
1999-02 Ford E350 Econoline Club Wagon with Single Rear Wheels (SRW) Rear Brake Pad & Rotor Kit
1999-07 Ford E350 Super Duty with Single Rear Wheels (SRW) Rear Brake Pad & Rotor Kit

[posplayr]

Originally Posted by arctictraveller

I’ve had the exact same issue for years until I investigated how much contact area the shoes had on the drum (hat on disc style).

I have Bosch shoes that I fit into the new rear drums. They look to be pretty good match (withing only 0.020" at the ends) except the last 1-2" of the shoes. I don't know if that is on purpose or not but at least it seems to be 70-80% matched.