Brake issues

[Longhorn Man]

Question...the brake fluid level in my master has been acting funny...some times one side will go low, while the other side fills up.

I have thought it was doing this for quite a while, and I verified it...so now, WTF is goin on?
(4 wheel drum 2 wheel drive non power assist)

[stelth2002]

Must be jumping over that rubber gasket on the top. Its the only spot that connects the two to my limited knowlegde. By the way, which so you think are more effecient as far as less drag drums or discs? Take into account the weight savings for discs(arent they lighter overall).

[walker]

I had one MC that would pump fluid from the front well to the back well through the seals. Took me a while to figure it out. One new master cylinder later, problem solved.

[Gordo]

I vote for blowing by the piston seals. Replace or rebuild master.

[Longhorn Man]

That's what i was figuring, but I was wondering what the internals of the proprtioning valve (or what ever it is called on 4 wheel drum)
Drums are lighter than discs, and they have less rolling resistance.

[lukecp]

Sorry if i hijack this thread, but how is the factory braking system with factory 4-wheel drums on a '70 C20, assuming it is a power setup? Are the stock, large, drums worth upgrading to discs on the front or do they work pretty good? I have been less then impressed with drum brakes on C10's, but then again the disc setup on my C10 hasn't been working great latley, lol.

I might be able to get a running, driving '70 GMC C20 from a family member for very cheap, which supposedly has a good cab.

[Longhorn Man]

Teh brakes on a C/20 are huge compaired to the crappy C/10 delayers.

[lukecp]

Thats what i was thinking.....i can always tell a C20 from behind because the brake drums stick inward from the wheels, lol. I guess i will drive it (proably this weekend) and see how it feels. If it is good i wouldn't want to bother upgrading it, although i proalby can't afford it for quite some time.

[Bowtie67]

Originally posted by stelth2002
which so you think are more effecient as far as less drag drums or discs? Take into account the weight savings for discs(arent they lighter overall).

I looked in to this a while back and actually Disk Brakes weigh more than the Drum setup, Unless you want to get fancy with some nice Aluminum Calipers, and Light weight Rotors, with a standard disk brake setup you will be putting on a few pounds, 12lbs per side at least. as far as drum brakes and their stopping power go, there really isn't anything wrong with drum brakes, good squared up surface on drums for the most part work extremely well. the advantage of Disk Brakes are exceptionally better cooling for thos fast hard stops with bigger motors, with a stock engine setup and for someone who just cruises there is no real benefit to upgrading to disk brakes except looks. If the master, wheel cylinders, drums and shoes are all good they have absolutely no problem stopping the truck, if brake pedal has to be pushed excessively hard to stop try a booster.
I would be curious if some members could weigh out some of these items, a lot of people do these swaps and have the drums and backing plates just sitting in their garage or for some one who is doing the replacement actually weigh this all up. I will be running Granada rotors on my setup for know but will be upgrading later to much lighter stuff once I get my current projects done with. JMO

[lukecp]

I like discs better, they also seem to be easier to service than drums. Although it isn't very hard to service either, lol. With discs you just pull off the caliper with 2 bolts, pull off the rotor, drop out the pads, get the rotor turned, and drop in new pads, bolt everything back up and you are done. With drums you have to get all the springs and linkages back up together.
But, i really don't have any problems with drums. If they work good i see no point in upgrading, except maybe to some Kevlar pads.

18-wheelers use drum brakes everywehre. 10 drums total on the truck and trailer, lol. But the shoes are huge, around 12" or so wide. And they stop huge loads, like up to 80,000 lbs or so (not too sure on this number, i just unload them, not drive them, lol).

Also, don't drums go longer before having to be serviced?

[Bowtie67]

Originally posted by yellow72custom
Also, don't drums go longer before having to be serviced?

Actually when comparing disk and brake shoe life I cant say which would last longer on the front. the average disk pad (Front)) with Drum rear is 2 to 1, 50k Disk 100K drum rear. Some of the foreign jobs with all wheel disk I dont think they lasted anywhere near 100K. When ever I have ever purchased any type of used vehicle one of my first things is check the brakes if they look questionable I do new brakes cut rotors and drums. and I have never had to retouch them afterwards. even with new vehicles I purchase I have yet to replace any brakes at all. I have traded in vehicles with over 85k on them and never touched the brakes. I put a lot of higway miles on. You dont find very many drum fronts on the road and when I twisted wrenches you only saw 1 may 2 vehicles a year with drum brakes. I started working in garages in 1976 and there weren't to many even then and most guys did there own brakes back then. JMOP

[Castiron9]

Same thing was going on with my master..and So I had brakes checked out.....500.00 later new master and all the rear hardware replaced since one rear cyln. was leaking..She brakes fine now so I do not have any brake issues............

[1-PU70]

The clamping force is greater on drums. The only dowm side to drums is when it rains. You never know witch way it will pull.

[stelth2002]

I can agree with 1-pu70 as far as rain. But i wont be driving her in much rain if any. This will be a go fast truck. But i dont abuse it and dont make it to where i have to stop extremely fast. But i kow discs have more drag on them, but i thought they might be lighter. I have a discs brake setup that i could put on for nothing and just thought i would ask. I guess ill be keeping my drums cause they work great for me.