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Now that I’ve got the other major issues worked with my 1979 F-250 4WD I need to address brakes. My truck has dual piston out front and drums on the rear. Brake pedal feels ok and I think vacuum is decent enough (12” at idle) but I have to stand on them to get a decent stop. If I really stand on them it will lock up the rears quick. The booster appears “newer” and I replaced the leaky MC and was able to bleed backs and pass front. Driver front bleeder screw is corroded (caliper will be replaced) and I was afraid I was going to break it so that corner may have a slight amount of air. Pads are in good shape. All lines and proportioning valve appear to be in good shape.
Questions: Should I just replace the calipers/pads up front with the reman stuff I can find on Rock Auto or is there a better performing setup? Been searching for new stuff but not finding anything obvious. I don’t need anything crazy just factory type performance would be great.
Truck is 4wd, 460/C6, mild lift with 35” tires so plenty of mass to stop.
the disc brakes on these pickups were always more than adequate. but they aren't ever going to feel like the brakes on a new pickup, they just aren't.
a lot of the problem people have is buying the best wiz bang last forever pads and shoes they can get. the problem is lots of the time long life is achieved by less braking action. this is one place I usually buy the elcheapo pads and shoes. they may not last 250,000 miles but they stop you.
Make sure you rotors aren't glazed as well that can effect performance.
I’m going to say the brake rotors and caliper and the back drums are more than adequate for the job.
I’ll say the power booster is one area that needs a definite improvement on these trucks. The power boosters back then where just ok at best. Even though my truck is a F150 4x4 Shortbox (‘77) I always felt the same way. It stopped ok but always felt I had to stick my foot into the brake pedal. So this spring I went and changed out my stock power brake booster and converted the truck to Hydroboost brake master cylinder. All I can say is oh my god what a difference it made!
You can source used parts and put a Hydroboost brake unit together but I don’t have the time to go to pick and pull junk yard or by this or that part etc....so I bought a complete conversion kit from WildHorses4x4. You can search my name on here as I did a post/thread about it.
You can also search Hydroboost brake conversions on this sight and see what other guys did.
I have 79 f250 brakes under my 66. and they stop on a dime with minimal effort. Maybe your vacuum is a little low @ 12hg, mine run a consistent 20hg. I also run a proportioning valve on the rear.
My truck has a 460 in it and pulls just shy of 20hg of vacuum. So as Christmas pointed out the vacuum could be an issue but as long as the system is full at the time of first hitting the pedal he should be fine. My 68 Firebird has vacuum brakes and the engine makes a tick over 550hp. Has low vacuum but until I have to hit the pedal more than 3x it doesn’t get really hard to push.
Cowboying up to it? I’ve done my fair share over the years and as the saying goes....work smarter not harder. Maybe I am spoiled with the newer vehicles now a days as well but all I’ll say is the effort it takes to push the pedal with the Hydroboost system also put a lot more confidence in the ability to stop the truck. Especially when pulling a trailer with even a moderate load on it let alone a heavy load.
It just makes it that much more pleasurable to drive over all.
For the front brake pads the Motorcraft BRSD provide some of the best durability and stopping power. They are still made for these trucks. You need to get your vacuum above 12 or install an electric vacuum pump to get up to 20 minimum.
My truck has a 460 in it and pulls just shy of 20hg of vacuum. So as Christmas pointed out the vacuum could be an issue but as long as the system is full at the time of first hitting the pedal he should be fine. My 68 Firebird has vacuum brakes and the engine makes a tick over 550hp. Has low vacuum but until I have to hit the pedal more than 3x it doesn’t get really hard to push.
Cowboying up to it? I’ve done my fair share over the years and as the saying goes....work smarter not harder. Maybe I am spoiled with the newer vehicles now a days as well but all I’ll say is the effort it takes to push the pedal with the Hydroboost system also put a lot more confidence in the ability to stop the truck. Especially when pulling a trailer with even a moderate load on it let alone a heavy load.
It just makes it that much more pleasurable to drive over all.
My 77 F-100 will throw your head through the windshield if you slam the brakes. My 78 Bronco will absolutely not. lol. Even with power brakes the Bronco requires so much more foot pressure to even suggest it to stop and it in no way will lock the wheels up if I stomp on it with both feet. It's been that way since I bought it and I've gone through everything on the braking system. It brakes just well enough to drive around town provided I don't need to make a panic stop. I actually bit the bullet and ordered a hydroboost kit from wildhorses as well, but it's been on backorder since the end of May. Not sure if it'll ever ship...
Com'on now. high school girls pulled horse trailers with these pickups but now we can't make it to the Dairy queen and back without leg fatigue ? I must be getting old I'm sounding like my dad. but I'm not to old to push the brake peddle yet so that's good.
Thanks for the responses! I didn’t intend to start a debate. Before I bought parts I just wanted to make sure I wasn’t missing the boat. Definitely not expecting it to stop like my 2017 Ram 2500 just thought replacing the 40 year old calipers couldn’t hurt. Again I appreciate the help.
My 79 F350 had OK brakes with new master cylinder, rebuilt calipers (rebuilt by me) new pads (ceramic) and rebuilt rear drums. This system was alright but I wanted it better. I swapped to a brake booster from a 2005 F150. It’s a 10” dual diaphragm. The difference is night and day. Now it brakes like a new truck.
What engine are you running to only have 12” vacuum? Unless you have a very well built motor I’d go look at what’s causing such low vacuum.
My 79 F350 had OK brakes with new master cylinder, rebuilt calipers (rebuilt by me) new pads (ceramic) and rebuilt rear drums. This system was alright but I wanted it better. I swapped to a brake booster from a 2005 F150. It’s a 10” dual diaphragm. The difference is night and day. Now it brakes like a new truck.
What engine are you running to only have 12” vacuum? Unless you have a very well built motor I’d go look at what’s causing such low vacuum.
It’s a modified 460. Not 100% sure of all the mods. I’m 95% sure it’s got a moderate cam. Based on several things including idle characteristics. It’s got headers and Atomic EFI. I suspected a vacuum leak but cannot find anything after some checking. Doesn’t burn oil, was only down 1/2 quart after 2000 miles and has a minor rear main seal leak that probably accounted for most of that. It runs great but in order to get it to idle consistently I’ve got to set it up to 750-775 in gear which results in 1150 or so in park (which is one thing that points to at least a mild cam). It also runs better on the mild cam setting (vs stock) on the Atomic tuner. I still need to replace the vacuum line from booster to manifold but I don’t expect to find a significant leak there because it appears to be in good shape.
EDIT: Just did some testing and I have 15” vacuum at idle in park but it drops to 11” when idle in gear. My experience is limited in this area but based on extensive reading this seems normal for a modified engine with a moderate cam?
It’s a modified 460. Not 100% sure of all the mods. I’m 95% sure it’s got a moderate cam. Based on several things including idle characteristics. It’s got headers and Atomic EFI. I suspected a vacuum leak but cannot find anything after some checking. Doesn’t burn oil, was only down 1/2 quart after 2000 miles and has a minor rear main seal leak that probably accounted for most of that. It runs great but in order to get it to idle consistently I’ve got to set it up to 750-775 in gear which results in 1150 or so in park (which is one thing that points to at least a mild cam). It also runs better on the mild cam setting (vs stock) on the Atomic tuner. I still need to replace the vacuum line from booster to manifold but I don’t expect to find a significant leak there because it appears to be in good shape.
EDIT: Just did some testing and I have 15” vacuum at idle in park but it drops to 11” when idle in gear. My experience is limited in this area but based on extensive reading this seems normal for a modified engine with a moderate cam?
With that vacuum reading its a no brainer, you need a vacuum pump. You are never going to get decent braking with those figures. That or go to hydroboost assist.
It’s a modified 460. Not 100% sure of all the mods. I’m 95% sure it’s got a moderate cam. Based on several things including idle characteristics. It’s got headers and Atomic EFI. I suspected a vacuum leak but cannot find anything after some checking. Doesn’t burn oil, was only down 1/2 quart after 2000 miles and has a minor rear main seal leak that probably accounted for most of that. It runs great but in order to get it to idle consistently I’ve got to set it up to 750-775 in gear which results in 1150 or so in park (which is one thing that points to at least a mild cam). It also runs better on the mild cam setting (vs stock) on the Atomic tuner. I still need to replace the vacuum line from booster to manifold but I don’t expect to find a significant leak there because it appears to be in good shape.
EDIT: Just did some testing and I have 15” vacuum at idle in park but it drops to 11” when idle in gear. My experience is limited in this area but based on extensive reading this seems normal for a modified engine with a moderate cam?
It takes a pretty big cam to only have 15" of vac at idle. I have a edelbrock performer cam in my 400 and it pulls 22" of vac at 800 RPM not in gear. I would say this is a RV type cam.
I think you may have something wrong with either a vacuum leak or a bad cam (flat cam lobe or two). A cam that would only pull 15" vac on a 460 and wouldn't idle at less than 1000 would be big and would idle really rough/choppy.
What is your initial timing set at?
Now with all that.... it still may be your brake system that is having a problem. Here are some questions to test your brake booster for leaks? How long after you turn your engine off does the booster hold vacuum and after the engine is turned off is the brake peddle still easy to push down once and then get harder after that? If you disconnect your booster and plug the vacuum line does your engine vacuum go up? Does your engine vacuum change when you press the brake peddle when in idle?
