Drum brake info and fluid question

[Zedyone_kenobi]

I have taken on a new project. Decided to totally redo my rear drum brakes. Getting off the rear drum was a bit tough. Lots of convincing needed. I still have the Aluminum Drums. One thing I noticed was that the pads I took off the car were stamped AKEMBORO, I think. I was wondering if these were the stock shoes.

My car just turned 70400-ish miles. And I do have relatively new wheel cylinders. The shoes I got are from Japan as well. Kashiyama I think.

That was not my question. My question is can I use DOT4 fluid when I currently probably have DOT3. I was going to get some DOT 5 silicone based fluid, but I was not sure if it was compatible.

Just curious. So far I have one side done and still need to get both DRUMS turned. I hope I still have some life left. I would like to keep the aluminum drums as long as possible.

[Arne]

DOT 4 will mix with DOT 3 just fine. DOT 4 has a bit higher boiling point, but tends to absorb water quicker. That's why European cars (which typically use DOT 4) have a lot more recommended fluid changes and flushes.

DOT 5 is NOT at all compatible with either of the glycol-based fluids (DOT 4 & 5). To change to DOT 5 you will need to flush all the lines with alcohol and then blow through with air. Most experts also recommend that all rubber parts be changed when changing to DOT 5, including all hoses and the hydraulic cylinders, or at least the rubber seals inside. Additionally, DOT 5 is more compressible than the others and so tends to deliver softer pedal feel and a bit more travel.

[Darrel]

I don't see why people want to use anything other than dot 3 on a street driven car.

Now if you were to take it to the track a few times a month then yes.

I still use dot3 and take my car to the track at least twice a year. You just want to make sure you have clean fluid before track events. But then i don't follow that rule either.

I'll have to try and take my to the limit tomorrow at the track.

[Zedyone_kenobi]

THere is a trackday coming up in March, that is the ONLY reason I am swapping out all the pads and fluid. I just wanted to be absolutely sure all my stopping bits were in tip top shape. I still had quite a bit of shoe left on my rear brakes when I removed them, but they looked really shiney, also noticed that the car did not want to roll while in neutral. With the driver rear jacked up, and the car in neutral, with the E-brake off, the tire was still VERY hard to turn. I know some dragging of the shoe is normal, but I think I may have had something out of whack.

[Doehring]

DOT 4 works fine! Don't you think about an improvement of your front brakes, they have to do most of the braking work.

[Zedyone_kenobi]

Agreed, they are next. But I know I have plenty of pad on the front. I never knew about the drums..

[Zedyone_kenobi]

Rear drums are turned and ready to go back on. Both wheel cylinders look fairly new, so I cleaned them up, applied some lube to the adjustment wheel, and installed my new shoes.

I just have to get the new drums measured to be sure they are within the 9.055" max allowable ID, as the parts store was not able to measure it :stupid:

I was wondering what people would suggest to put between the aluminum drum and the steel hub to keep it from sticking due to corrosion. Anti seize comes to mind, as does some brake grease, any other suggestions. Paint would work right up until I actually put the drum on the hub when the close fit would scrape all the paint off.

I should have this done by wednesday, as my mityvac brake bleeder kit comes in Tuesday. Then its by by old fluid, hello new.

[Darrel]

I had a great track day yesterday. But I was missing one thing and it became apparent during the hard braking areas of the track. I couldn't stop so i decided to bleed the brakes in the paddock. I got everything out, miracle whip jar, the glass kind, 1mm wrench for the solo bleeders from russel(great solo bleeders btw). Then I looked for my brake fluid, DOH!!. I left it sitting in my shed. Nobody had any dot3 in the paddock which i expected. So I drove 40 rt to the nearest napa store. Got back, bled the brakes and everything was right with the world.

I even stalked and passed a ferrari. Granted he was just poking along, but I passed him none the less. I know you're going to say why I didn't get it on camera. I wold have except my rechargable batteries aren't so rechargable when it real cold out. I really need to get it hard wired into the car.

[esmit208]

Hey ZED

Why don't you just convert to disc brakes on the rear. The stopping power is better and you are only allowed one machining of the drums. So eventually you will have to have new drums anyway. Also to have truly effective stopping power with drums the slack adjustment has to be made periodically.

2MUCHZ

[hogie]

Doesn't the e-brake adjuster automatically get the slack out?

[Zedyone_kenobi]

yes, it does, by design every time you pull it, it moves a lever on the wheel cylinder and ensures the shoes stay in approximately the right position to function properly.

You are right esmit208, but a full rear brake upgrade will cost about 800 bucks and while I still have life in my aluminum drums, I will use them. They measured 9.008 and 9.015". Max ID is 9.055, so even after turning, they are still within spec.

The chances of me wearing down my rear drums again are close to zero in the limited fun driving I do, so if I feel I need more braking, I will probably go with the toyota 4x4 brake upgrade for the front. Or the front disk upgrade from MSA, which is essentially the same thing.

Edited February 1, 2010 by Zedyone_kenobi

[Zedyone_kenobi]

Well I just used the coolest tool... I picked up one of these...

What a cool tool to use. Beats saying "PRESS", okay "LET UP", okay "PRESS"..

Has anybody used one of these before? I have a couple of questions.

I pulled the master cylinder down 3 times, and completely flushed the old dirty fluid out, but Never did get a solid stream of liquid from the rear drums. I still got MOSTLY air with a trickle of fluid from both sides of the rear drums. There is absolutely NO way I could have had that much air in the system and stop the car. I think when pulling a vacuum, I am also getting air in from around the nipple and around the threads.

The good news is even if I am sucking in air from around the bleed nipple I cannot be introducing more air as long as I hold a vacuum. That is why I love this tool. It is almost impossible to mess up bleeding the brakes.