Emergency Brake Delete on Rear Drums?

[Corte's Speed Shop]

I'm working on my P10 project and have been addressing the rear end. I have everything cleaned up and am running drum brakes in the rear using ECE's rebuild kit.

I'm wondering if I can delete the emergency brake components inside the drum and whether the braking mechanisms will still function properly. I have most everything assembled, sans e brake lever and the strut/spring. The first picture is my setup and the last two pictures show the components I'm referring to.

Does anyone have any insight as to whether or not the brakes will work properly if set up this way?

[jayoldschool]

It will work fine without the strut, spring,and SA arm. All were missing on my truck. However, WHY? I paid good money to buy those parts and have a functioning parkijng brake.

[Vinceg]

Your Brakes will work just fine without any of the E Brake components as stated. I’m with jayoldschool. Maybe because I have had to use my Emergency Brake in times past. First time was my first 66. I had a line blowout with the single master cylinder. E brake kept me from having a major accident. It was a close one. I was sitting a few inches higher in the seat after if you know what I mean. The other times it has been to keep the vehicle from rolling while changing a rear flat tire. Chances are you might never need it. Then again it is called EMERGENCY BRAKE for a reason. I do know it won’t pass a safety inspection where I am without it.

[dracko]

You must not be in a cold climate where you need to warm up the engine in the morning. OR have an auto transmission..

[AcampoDave]

http://67-72chevytrucks.com/vboard/s...d.php?t=684914

[jocko]

Keep in mind that it isn't ok to use Park in an auto trans as a substitute for a parking brake - and most states check for its presence even if not whether it functions. There's no reason to delete it, should be a part of every brake system.

[Corte's Speed Shop]

Thanks for the info, fellas. I should've specified I'm planning on using cupped lower control arms and air bags to have the front control arms on the ground when aired out.

I know not having the emergency brake is a risky proposition, however, I feel for my needs and intended usage, it shouldn't be a concern. That being said, I'll hang on to my old emergency brake components in case I change my mind later.

[jocko]

While less likely to occur, sliding down the hill you were previously parked on is probably just as expensive as rolling down it.

[Mack B]

Originally Posted by jocko

While less likely to occur, sliding down the hill you were previously parked on is probably just as expensive as rolling down it.

If the weight of the truck on the ground won't stop it from rolling/sliding, surely the brake pads don't stand a chance?

If anything a complete failure of the braking system would be my concern, I don't know the statistics on complete failures on dual reservoir systems tho.

[AcampoDave]

Are you sure ? If you are already going to be dropping serious $ into your suspension why not up the ante a bit more and go with something really trick like this http://www.speedwaymotors.com/E-Stop...SABEgKEdfD_BwE then you can have it all in one package... Anti theft device, and the ability to lock 'em up in an emergency.

[rvrfoot]

Is your truck a auto or a stick?

[jocko]

Originally Posted by Mack B

If the weight of the truck on the ground won't stop it from rolling/sliding, surely the brake pads don't stand a chance?

If anything a complete failure of the braking system would be my concern, I don't know the statistics on complete failures on dual reservoir systems tho.

On a flat surface, sure, you’re gonna be fine. But on a grade, you’re rolling the dice. The weight works against you eventually. A couple pebbles squatted on will make for a truck slipping down the hill. The rubber contact patch of the tire on the pavement provides the friction to keep you sliding or rolling when not allowed to rotate by a parking brake. Mere weight of a vehicle that is resting by its frame on a bunch of pebbles is not a valid parking brake system.

Keep in mind that your total brake system has nothing to do with not rolling when parked. At that point it is based on the parking brake system only, a separate system. Or it’s your trans parking pawl absorbing all the stress if you are relying on an auto trans to save the day. Until it breaks.

The only correct answer is to have a brake system built to not fail and to have a separate parking brake system. I’m not trackin the resistance to including it.

[Mack B]

I'm assuming this:

Originally Posted by jocko

Keep in mind that your total brake system has nothing to do with not rolling when parked.

Is in response to this?

Originally Posted by Mack B

If anything a complete failure of the braking system would be my concern, I don't know the statistics on complete failures on dual reservoir systems tho.

I'm aware, I was referring to using the emergency brake as an emergency brake and not a parking brake in that line of thinking.

Originally Posted by jocko

On a flat surface, sure, you’re gonna be fine. But on a grade, you’re rolling the dice. The weight works against you eventually. A couple pebbles squatted on will make for a truck slipping down the hill.

I'm not an engineer...and this next question will probably confirm that to any doubters . How steep of a grade does it take to overcome 3,700lbs laying on 6' of frame rail x2 plus the crossmember? Surely before that point we would need to worry about a truck at ride height sliding on its tires down the same hill?
I do get the idea that it could be a sled, but I can't imagine it in a real life scenario.

[jocko]

While I can’t recommend what grade hills to avoid parking on, I would not be willing to find out the hard way with my own truck. There is a reason GM uses the tires to prevent movement. I guess I’m a little surprised that this is one of those things that folks at least appear to be arguing in favor of (pb elim). An emerg brake IS a parking brake. It’s meant to prevent movement when parked, not for locking up the wheels when you think your other two independent brake circuits have failed. The two hydraulic brake circuits are their own backup from 67 forward. To address the valid concern over the lack of redundancy in a 60-66 braking system, the answer is to add a 67 or later dual reservoir master cylinder, just like GM chose (or was required ) to do.

[Mack B]

Originally Posted by jocko

While I can’t recommend what grade hills to avoid parking on, I would not be willing to find out the hard way with my own truck. There is a reason GM uses the tires to prevent movement. I guess I’m a little surprised that this is one of those things that folks at least appear to be arguing in favor of (pb elim). An emerg brake IS a parking brake. It’s meant to prevent movement when parked, not for locking up the wheels when you think your other two independent brake circuits have failed. The two hydraulic brake circuits are their own backup from 67 forward. To address the valid concern over the lack of redundancy in a 60-66 braking system, the answer is to add a 67 or later dual reservoir master cylinder, just like GM chose (or was required ) to do.

This post before the edit suggested you would be the one I could ask about a question I have: How steep of an incline would it take to cause a 60-66 truck (let's assume shortbed c-10) to slide on its frame down a hill?

Of course GM went with brakes at the wheels for e brake purposes, a truck that could potentially contact the pavement in driving conditions is a serious danger and real possibility of happening, but we do these things anyway, because the likelihood something bad will happen is low......same with using said airbag system as a parking brake.

Not splitting hairs, was the original intent in our trucks to only use the e brake for parking, or did it offer a back up to the single master system? It's before my time and I honestly don't know. I realize later model's safety systems have made emergency use almost obsolete, but no matter what I'm driving, if I can't stop it any other way I'm pulling it...that's after the engine has kicked the rods out of course

[Tiger Joe]

I have seen an air bagged truck with no parking brake slide down a steep driveway when aired out.

it was a 70 c10 LWB. bagged and laid frame. owner aired it out as his parking brake. they got the truck stopped by jumping in a stepping on the brake.

[jocko]

Mack, my edit was to add the note about 67 and later master cylinders providing redundancy in the system in case anyone wasn’t aware (forgot I was on the 60-66 board for a second...hang out on the 67-72 side as well). I am an engineer, but can’t really give you an exact number of how steep a grade would pose a risk - but tiger joe has provided a data point that should make anyone considering airing out as a substitute for a parking brake take pause. You do pose a good question on why the term emergency brake was used in the past. I’ve used it myself - interchangeably with parking brake, and indeed I’d use it as a last resort if a brake system failed. I guess my main point, which I could have worded better, is that if someone is going to spend money on an airbag system, they can afford a parking brake - and if available funds cause one to choose between the two, then a parking brake should take priority - and air it out later. The OP asked a good question - airing out would keep the vehicle from rolling on fairly level surface, but joe provided some proof it won’t work for all surfaces.

[Mack B]

Originally Posted by Tiger Joe

I have seen an air bagged truck with no parking brake slide down a steep driveway when aired out.

it was a 70 c10 LWB. bagged and laid frame. owner aired it out as his parking brake. they got the truck stopped by jumping in a stepping on the brake.

That's all the proof I need . My only experience was with a bagged and body dropped truck that the engine couldn't even move when laid out...in retrospect the front tires where unable to rotate on said truck was laid out tho.

Originally Posted by jocko

Mack, my edit was to add the note about 67 and later master cylinders providing redundancy in the system in case anyone wasn’t aware (forgot I was on the 60-66 board for a second...hang out on the 67-72 side as well). I am an engineer, but can’t really give you an exact number of how steep a grade would pose a risk - but tiger joe has provided a data point that should make anyone considering airing out as a substitute for a parking brake take pause. You do pose a good question on why the term emergency brake was used in the past. I’ve used it myself - interchangeably with parking brake, and indeed I’d use it as a last resort if a brake system failed. I guess my main point, which I could have worded better, is that if someone is going to spend money on an airba system, they can afford a parking brake - and if available funds cause one to choose between the two, then a parking brake should take priority - and air it out later. The OP asked a good question - airing out would keep the vehicle from rolling on fairly level surface, but joe provided some proof it won’t work for all surfaces.

I'm all fairness I enjoy the discussion on these things, In my mind the op had a solid rational about ditching the e brake...My only stake in this is I have porterbuilt trailing arms on the way and I'm not sure there is a clean way to route the cables with these, even at that I considered a different style than total deletion.

[jocko]

Might be worth looking into a driveshaft parking brake if room is tight. Enjoy the discussion too - all good

[nsb29]

Originally Posted by Mack B

That's all the proof I need . My only experience was with a bagged and body dropped truck that the engine couldn't even move when laid out...in retrospect the front tires where unable to rotate on said truck was laid out tho.



I'm all fairness I enjoy the discussion on these things, In my mind the op had a solid rational about ditching the e brake...My only stake in this is I have porterbuilt trailing arms on the way and I'm not sure there is a clean way to route the cables with these, even at that I considered a different style than total deletion.

Why don't you cut 4 1 foot sections of thread from an old tire and bolt them to your frame then in an emergency you could just lay the frame LMAO

[Mack B]

Originally Posted by nsb29

Why don't you cut 4 1 foot sections of thread from an old tire and bolt them to your frame then in an emergency you could just lay the frame LMAO

Sir, you should have patented that before throwing it out there!

[jocko]

That’s actually a pretty good suggestion for a parking brake. This would provide the same grip on a surface that a parking brake does with tires, assuming approx same patch size. Hard frame rail will slide over small rocks like assembly line rollers, but a tire patch with weight on it will not.

[nsb29]

Originally Posted by jocko

That’s actually a pretty good suggestion for a parking brake. This would provide the same grip on a surface that a parking brake does with tires, assuming approx same patch size. Hard frame rail will slide over small rocks like assembly line rollers, but a tire patch with weight on it will not.

LMAo I should've been an engineer never had a any desire to lay my frame but if I did I would do it to protect all my work and I thought I was just being a smart azz

[cru_zn_29]

You need to watch out those smart a$$.

[nsb29]

Originally Posted by cru_zn_29

You need to watch out those smart a$$.

Yeah they pop up when you least expect them LOL