When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Need some guidance on brakes. I still have original drum brakes on it but everything has been replaced on them including the master cylinder, except the lines and they look like they were replaced by the previous owner. Took the truck out on it's maiden voyage yesterday. When I started the trip they would stop on a dime with the brake petal about 1/2 away down to the floor, but the further I went the worse the brakes got. To the point of having the petal as far to floor as I can press it and very little stopping power.
Got it back home. Parked it, went out a few hours later and brakes were back at full power. I don't see any leaks but could be hidden I guess. Got to try and figure this out before I head out again but not sure where to start
Wonder if they were not fully bled? Sitting allowed gravity to move some air around? Another thought is something sticking and not retracting, thus not allowing sufficient fluid return. What is the current level in the master cylinder? If it is on the low side, could be a leak, could be air being displaced by the force of gravity, or something stuck and not retracting... If it is "normal", that could indicate something sticky has slowly returned over time. These are just starting thoughts and not necessarily exhaustive.
Wonder if they were not fully bled? Sitting allowed gravity to move some air around? Another thought is something sticking and not retracting, thus not allowing sufficient fluid return. What is the current level in the master cylinder? If it is on the low side, could be a leak, could be air being displaced by the force of gravity, or something stuck and not retracting... If it is "normal", that could indicate something sticky has slowly returned over time. These are just starting thoughts and not necessarily exhaustive.
Thanks! Yeah checking the fluid was the going to be the first thing I do. Unfortunately, won't be as easy as before since I have installed carpet and got everything covered. Tried to make sure all that was good before installing it but we know about the best laid plans!
Thanks! Yeah checking the fluid was the going to be the first thing I do. Unfortunately, won't be as easy as before since I have installed carpet and got everything covered. Tried to make sure all that was good before installing it but we know about the best laid plans!
if you’re not going to use a remote reservoir master cylinder, you might wanna go ahead just cut a hole in the carpet for access to the master cylinder. The rubber cover that goes over the top of the hole is pretty good and you can always put a floor mat on top of that. when I did my brakes, I jacked up on all four corners on Jack stands, pumped them up and held him to the floor with a stick, and then started bleeding the brakes from the front all the way to the back. You can also, as I learned later, take a bottle halfway full of brake fluid and a rubber hose all the way to the bottom of the bottle, preferably clear, and attach that to the bleeder valve and crack it open, and that will keep the air from going back into the system, and you can just pump the brakes from the front and it will bleed the brakes out. Once you have all the brakes bled, you can go to each wheel and try to turn them with your hands. If they turn, you might have another issue. I tried to turn them. By turning them manually you can also see if they’re adjusted correctly.I wonder if the master cylinder have been benched bleed before it was installed, that can always cause havoc and your brake system.
if you’re not going to use a remote reservoir master cylinder, you might wanna go ahead just cut a hole in the carpet for access to the master cylinder. The rubber cover that goes over the top of the hole is pretty good and you can always put a floor mat on top of that. when I did my brakes, I jacked up on all four corners on Jack stands, pumped them up and held him to the floor with a stick, and then started bleeding the brakes from the front all the way to the back. You can also, as I learned later, take a bottle halfway full of brake fluid and a rubber hose all the way to the bottom of the bottle, preferably clear, and attach that to the bleeder valve and crack it open, and that will keep the air from going back into the system, and you can just pump the brakes from the front and it will bleed the brakes out. Once you have all the brakes bled, you can go to each wheel and try to turn them with your hands. If they turn, you might have another issue. I tried to turn them. By turning them manually you can also see if they’re adjusted correctly.I wonder if the master cylinder have been benched bleed before it was installed, that can always cause havoc and your brake system.
thanks again, I did not realize they made a remote reservoir! Sounds like something worth its money and doesn’t look to hard to install. Gonna look into installing one after I figure this issue out,
What is the time between everything brake wise was replaced and the maiden voyage? I replaced everything brake associated on my drum brake system including all brake lines, my truck sat for some time before my maiden voyage. Everything worked fine the first few times I took it for a test drive. One day the left front brake started dragging, thought maybe I'd adjusted it to tight, long story short, from sitting so long, condensation had evidently built up to the point corrosion had rusted the inside of the brake cylinder causing it not to retract all the way. Every time I used the brakes it forced more contaminated fluid into the cylinder, the cup could not retract all the way. I ended up replacing both front brake cylinders, flushing the entire brake system with isopropyl alcohol, filled with fresh brake fluid. I've had no more problem since.
Last edited by 55F250; Nov 22, 2025 at 10:18 AM.
Reason: Should have said left front
Does the master cylinder have a residual pressure check valve? I think that the originals had it built in but if you put a modern master cyl on you have to add inline check valve(s)
I'll just add that I have a stock system like yours and have always had problems bleeding them. No matter what was checked or replaced it still seemed that there was some air in the system. I finally bought a Phoenix Reverse Brake bleed tool (model V5) and that finally got them bled. It works by pumping brake fluid into each brake cylinder bleeder forcing the air out of the wheel cylinder and lines and out the un-capped master cylinder. To me its sort of a messy operation. But it works very well. If you are using speed bleeders you will want to make sure you replace those with normal ones before using this tool as the speed bleeders will block the brake fluid from being pumped in by the tool. If you do use the regular method such as a piece of clear tubing and a cup with some break fluid in the bottom, try to get enough tubing that will feed the brake fluid up and then goes down into the cup. Any air in the system will want to rise, so you will want to create a "trap" that will keep the air from getting sucked back into the wheel cylinder.
If you are interested in a Phoenix they sell them at Auto Zone, Napa, Amazon, etc. Last price I knew was around $70. True its some money but you will pay at least that in a brake shop.
The master was changed out back in 2018 or 19 when I took possession of the truck. We replaced with one of the standard master cylinders you find at lmc and other sites. Not sure if it had the built in check valve or not. The truck has been sitting since the 90s and everything was seized on them. We were able to free up all the brakes but changed the master at that time. Then as sometimes happens life got in the way and the truck took a back seat till last year when I got back on it.
All the pistons, springs and pads even the ebrake cable was changed out just a couple months ago. And we have bled the brakes and adjusted them twice since then. Got some time tomorrow afternoon gonna check the fluid and bleed them once again to see if that helps.
Appreciate all the suggestions!
Last edited by g-money-55; Nov 22, 2025 at 08:40 AM.
Some free advice, worth what you pay for it, I would ditch the single bowl master cylinder and replace it with a dual bowl, not that more expensive and a lot better all the way around. Not to mention the safety issue with a single bowl.
Some free advice, worth what you pay for it, I would ditch the single bowl master cylinder and replace it with a dual bowl, not that more expensive and a lot better all the way around. Not to mention the safety issue with a single bowl.
would you use that along with the remote reservoir or is that either or situation between it and the dual bowl?
also looks like we’re fairly close neighbors. I’m over in El Dorado
Whichever remote reservoir is used will need to match whichever master cylinder is used. There are many aftermarket offerings out there that provide these features for our smaller trucks. Note that these things may not address your current root cause, so don't get sidetracked. Determine the issue first, then devise a remediation plan which could include these aftermarket components.
I agree with bmoran4 completely, need to figure out what is going on first.
did you check the fluid level, sounds dumb but I would also check the side of the tires under the truck and see if there is any fluid on them. Might be a leak letting air in the system. When I replaced my lines I had the truck on jack stands, pimped the breaks up and used a pool cue to hold the pedal under pressure. Came back in an hour and found a leak, I did this a few times with good returns.
i had my original style master cylinder fail on me and that is the main reason i went with an upgrade. There are of course safety, power brakes are available, proportioning valves if you want to go disk in the future (front, back, both) remote reservoir, and even low pressure warning light. I did mine at home and it worked out great for me.
Yeah, we are about 2 hours away on 82, small world in this group but a lot of knowledge and help.
So I started working on my 1953 F600. I drained the hydraulic oil last night and there was a quart of water to the three quarts of dirty hydraulic fluid. I am going to clean the tank, and pump and then put it back on. The guy I got it from showed me it works, but it was they were slow. Well with all that water, it is a wonder it worked at all. The engine ran great, and I listened for anything amiss and it was fine, it just run rough. Well the gas was ethanol, and both filters are full of of sediment so the gas looks like oil diesel. That is next on my list of draining and clean, so I can get it to run right. Oil and antifreeze are next which I am sure are in need of maintenance. Tires are last because they are the most expensive. They are good enough to use on the farm for now, but I will change the wheels and tire to use here . I need to check the brakes, because they are all new breaks lines and looks like new brake cylinders, but I have to confirm that and really do not work. I am used to much smaller juice brakes. I have a 1948 mechanical bark Hartley and an 1968 juice brake Harley, so the brake lines are sorter and the brakes easier to b bleed. I want to put a dual master cylinder on it, but I am not sure which one to purchase. If I can get some help from you guys, I will change it before I mess with bleeding the brakes.
@wolfcoln , the F600 is a completely different beast and the aftermarket kits for the smaller trucks are not appropriate. I'm not aware of any commercial offerings for the larger trucks. Stock style components such as master cylinders and wheel cylinders are generally available though. You can reline your existing shoes. Drums are extinct, so you got what you got, or you find some some better used ones (typically it is a whole truck, whole chassis, or whole axle type purchase).
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
