Okay, I just wrapped up doing the brakes all around (new pads, rotors, shoes, drums, and hardware), and when I went for a test drive, my braking is now horrible. Feels like you're stepping on a swollen wet sponge, and the stopping power is **** near non-existent unless you pump the hell out of the petal.

I cracked no lines, so I caint see how I could have gotten any air in the system.

I know I saw a teeny tiny bit of brake fluid coming from the driver side rear wheel cylinder boot, but I don't think that would really have made all that difference. I mean it stopped better before with pads and shoes with no friction material eatin through rotors and hubs even with that super slow leaking wheel clinder.

And no, they aint glazed either. Took a non directional to both for better seating before I put em on, and wiped off the shavings with some cleaner and clean shop towels.

I'm at a loss as to what else causes spongy brake petal...

 

Did you adjust the rears out? I would go and do a brake fluid flush also... AFTER you replace the wheel cylinders! My .02

 

I agree with Mr. Big Ram, sounds like you need to adjust the rear brakes, and i would go ahead and replace the wheel cylinders. They are cheap insurance if you don't do it now, you'll be doing it when they leak and ruin your new shoes. Good luck.

 

Yeah I adjusted them all nice like. Way I've always done it was to screw it all the way in, then put the drum on and adjust from the outside till you hear the shoes barely catching friction on the drums. My parking brake feels like your workin out on a leg press compared to before... So they're definitely adjusted right, afaik.

Now I didn't think to look, but all the springs and hardware has to come off to do the wheel cylinders right? No easy little tricky way to do it is there? Cause that took me 20 minutes per rear side! Not lookin forward to spendin that much time and cursing my lack of a spring tool again lol...

 

And also why would it be WORSE now with all around better brakes? That what just really blows my mind...

 

Welcome to owning a 12 valve truck. Search some of my posts and you will see that you could be in for a whole world of fun. I replaced everything in my system ( lines , wheel cyls , master cyl , calipers, etc) aside from the brake booster, and I STILL had no brakes. fast forward a year , and the brakes appear to have " broken in". I feel i have adequate braking power now.

 

Well an update on it, I borrowed a pressure bleeder, and bled the hell out of it. Some of the stuff that came out of there looked like the black silicon grease we use on machinery lol.

Guess when I pressed the pistons back in I broke loose some "goop" (for lack of a better word) that lined the inside of those steel lines, which took a pressure bleeder to dislodge from the bleed screws.

Seems to brake like a champ now. Still should probably get to the wheel cyls sometime though...

 

Do the wheel cylinders!!! unless you want to do everything over again, might be wise to watch those calipers up front also for a bit. a while back after I did a complete flush on a neighbors ride, they started leaking a few weeks later! that was alright, another side job for me !!

 

Just two springs need to be disconnected from one end, two bolts and the line and they're off.
Use Napa #4637337 cylinders for better stopping power than the stock ones.

Glad you found the problem but what often happens when doing brake replacement especally on a rig with dirty brake fluid is compressing the calipers back forces the dirtiest fluid in the system back which can damage the master or ABS unit causing poor braking.
Better to open the bleed screw before forcing the calipers down.

 

Yeah, I'll definitely keep that in mind next time whenever I do a brake job.

Now that napa part number doesn't pull up anything on their website for me. Is that just out of a 3500, or...?

 

1 ton chevy wheel cylinders

info from:

texawebslinger site

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http://dieselram.com/cgi-bin/ultimat...=001164#000000
The link above talks about;I just replaced the rear wheel cylinders on my truck with some cylinders for a one ton chebby. WOW!!! What a differance!!! The truck stops with about 1/2 the pressure on the pedal and seems to stop FASTER and it also seems more stable while hard braking too. Go to your local NAPA store and tell them you want wheel cylinder part number 4637337 or TSW4637337. They are a direct bolt in. The pistons are larger so the rear brakes work more. On mine the hardest part was getting the drums off. I must give credit where credit is due, Infidel over at DieselTruckResource.com posted the info.

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Also:

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I got this info from my old Cummins friend Bill Flemming

This is for changing out your rear brake cylinders from ¾ ton to 1 ton cylinders. First thing you need to do is go to your local auto parts store and ask them for GM part #4637337. DO NOT tell them you want GM 1 ton cylinders for your ¾ ton Dodge. You will only confuse them. They sometimes will tell you that they have a “cheap” cylinder and a “higher quality” one. I chose the higher quality one and paid around $80.00 for the pair, but they do come with a lifetime warranty. Might as well grab a couple cans for brake cleaner while you’re at it because you’ll need it.

Go home, block the front tires and jack the rear of the truck up. Place jack stands under the axle and remove both tires. Next you will need to remove the brake drums. They usually don’t come right off. What I did was take 2 lug nuts and spun them back on the studs on each side. I started the truck, put it in reverse, got the rpm’s up and hit the brakes hard. One drum broke loose, but the other didn’t. I had to take a heavy punch between the studs and strike it with a large hammer. It broke loose finally.

Your drums will probably not slide right off. Back off the adjusters a tad and it should slide off. Spray the parts down with brake cleaner and get things cleaned off. Now is a good time to look at your brake shoes while you have the drum off too.

You will need to remove ONE spring from the shoes to allow it to spread apart so you can get the cylinder out. (See Illustration) It is only necessary to remove the “forward” spring, meaning the one facing the front of the truck. This will free up the shoe so you can remove the cylinder.

Take a 3/8 wrench and remove the brake line from the back of the cylinder. Take a 13mm wrench and remove the two bolts securing the cylinder to the housing. Remove the cylinder.

The 1 ton cylinder is noticeably larger.

You will need to reuse the metal pieces that spread the shoes. (You will see when you do it). Put the new cylinder in, tighten the bolts and install the brake line back in. Also secure any springs that you removed. Put the drum back on and adjust the brake adjusters until the just barely drag on the drum. Start the truck and bleed the air out of the system. Put your wheels back on and you’re ready to go.

I had been battling hard pedal for almost 2 years and figured it was in my master cylinder/booster. After doing this my brake pedal is soft and I have awesome brakes now....
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follow on post, same thread:
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some comments from Bill


The 4637337 is a Napa number but will cross over at any autoparts.
You can even order online by clicking here

This part number and mod works on all Rams from '89 to '02 models till rear discs were introduced.

First time I did this mod the guys at Napa pulled out their low, medium and high grade cylinders. No one at the counter could tell the difference between them and in fact were confused on which box to put them back in.
Made me wonder if it was some sort of scam.

I went for the $13 model, been working great for several years.
I've done about twenty cylinder swaps, all with the $13 model, every single owner has been very impressed with the increase in stopping power. In fact it changed a couple of owner's plans to convert to discs or very expensive EGR brakes.

This is by far the most economical mod with the greatest results you can do to your truck. It will stop the way it's supposed to do, no nose diving and increased front pad wear since the rears are finally doing their share of the work. Only downside is the first time you go to stop, takes a little getting used to brakes that work right....
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Some more:
http://dodgeforum.com/m_498851/tm.htm

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The 30mm GM wheel cylinder swap is something I picked up from a bunch of CTD owners. They had been doing it to their trucks. And since all the 3/4 tons and 1 tons use the same type/style of wheel cylinder (with the exception of the ones with rear discs) I decided to do it on my truck, and the results were VERY noticeable and well worth the $30.

It's a simple mod to do and is very effective. You can see in the comparison below how much bigger the cylinders are.
GMC 1 ton -----------= 30mm = 1.18"
Dodge 1 ton----------= 27mm = 1.06"
Dodge pre-'97 2500-= 24mm = .94" (Though they have been found installed on POST 97 Heavy Duty Trucks)

The difference in stopping power between 30mm and 27mm is 23%! That may not seem like much, but it definitely is noticeabe out on the road! I know there are some people that think disc brakes are the answer, but for $30 you can have drum brakes that are just as capable as the disc brakes found on 01+ Trucks. And unlike the disc brakes, the drums don't have issues with mud and gravel getting in them...or slides seizing up. There's a good reason GM switched BACK to drums some on their trucks.

What you'll need for the swap is a set of 1 Ton GM wheel cylinders. Don't go to the *********** to buy them. Head down to NAPA or Bumper To Bumper...or order them from Rock Auto. Below are some part numbers. If you go into NAPA (or somewhere else to get them), DON'T tell them what you're using them for. That will just confuse them!

NAPA: 4637337
CARQUEST: SWC1025
WAGNER: http://www.rockauto.com/catalog/cata...8&a=FR5-F79768

They should run you anywhere from $8 to $15 a cylinder. I have heard of some costing as much as $40. DON'T get those...the cheap ones work just fine. In fact, the guy that came up with the idea specificly said to use the cheapo NAPA cylinders. I used Wagner cylinders in mine (they're probably the same) and I still noticed a huge improvement in braking. A warning though, the first time you use your brakes (after you have them properly adjusted) you will most likely lock up the rears. I know I did. That's beacuse you're used to using brakes that don't function very well. After a while you get used to using a lighter touch on the pedal.

A concern that some have had about this mod is the master cylinder. Some think that it doesn't have the capacity for the larger cylinders, but let me assure you that it has MORE than enough capacity for them!


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Awesome. Great info Invader. Thanks a bunch. Yeah since I'm gonna be replacing the wheel cylinders anyways, I'll DEFINITELY go this route. Always thought the rear brakes on my dodge were a little underpowered. Sweetness. Glad you posted this information.