Hi Guys, I have been reading this forum and working on my 78 3/4 ton club cab for a few months now. I believe that I need to change out my master cylinder and booster, the brakes are sloppy and I am losing vacuum. There is also a whine noise under the hood. I would like to increase the size of my booster for more stopping power and would like advice on a setup that would bolt in with out modifications that you guys have done....an example would be a mc/booster from a 90's 1 ton van. also any tricks/problems I should follow/look out for during the change out? Any ideas out there? Thanks, Tony
Speed Dragon
07-01-2008, 08:31 AM
A booster is a booster, for the most part. There are only 2 booster types, big and flat or small and fat. If you have a big block, you need to run the small fat one to clear the valve covers.
If you want more stopping power, you need to look into upgrading the master cyl, calipers and wheel cylinders, probably to 1-ton units.
Tony78/440
07-01-2008, 04:37 PM
Thanks, I will look into the calipers and such this weekend. The napa online lists the same p/n for the master cylinder on 3/4 and 1 ton trucks. Is there a difference?
Speed Dragon
07-01-2008, 05:35 PM
I guess not :) I know the rear brake cyl's got bigger, not sure about the calipers.
Tony78/440
07-01-2008, 08:08 PM
Thanks, there is a 78 1 ton,and a couple 3/4 ton trucks, as well as some 90's 1 ton vans in the yards around here. If the domestic supervisor lets me out for awhile this weekend I'll see what is left. Things go quickly in the yards around here. I picked up a perfect bird bath hood 2 weeks ago for $35 at the closest one.
Megunticook
07-07-2008, 07:32 AM
any tricks/problems I should follow/look out for during the change out? Any ideas out there? Thanks, Tony
I just replaced my booster and MC this spring, and have pretty much rebuilt the entire brake system over the past year and a half.
I got a rebuilt booster from RockAuto (Cardone A1), but there's a guy in Oregon named "Booster Dewey" who apparently does nothing but repair and rebuilt boosters. Price is comparable.
When you say your brakes are sloppy, can you describe the symptoms more specifically?
Getting the pushrod length dialed in just right is the only tricky part--basically just want the slightest bit of freeplay at the pedal, which translates to literally a gnat's a__ between the end of the rod and the MC plunger. If you get this wrong, you either get a low pedal or sticking brakes.
