1ton vs 3/4 rear brakes?

[ahale2772]

Im gona rebuild my rear brakes in a few weeks and im wondering if there are anyparts I can upgrade with. I know the front brakes have minor difference between 1ton and 3/4...is it the same out back?

can I use 1ton drums and shoes or are the hubs different? will the backing plates work with 1ton stuff?

what are a good brand of parts to go with? ive had good experience with parts from napa, but i can also get a discount from advance auto on most parts

thanks

[ellis93]

You can use your drums with the 1ton shoes. You just need to have them turned. All you need are shoes and wheel cylinders from a ton truck. I've read that the 3/4 cylinders will work but I can remember where I seen that.

As far as brand, wagner is about the best I've used and I think that Advance carries them.

[BobS]

You can use your drums with the 1ton shoes. You just need to have them turned. All you need are shoes and wheel cylinders from a ton truck. I've read that the 3/4 cylinders will work but I can remember where I seen that.

As far as brand, wagner is about the best I've used and I think that Advance carries them.

I have over 40K trouble free miles on the 3" rear brake shoes with the original 3/4T wheel cylinders.

[ahale2772]

my drums are completly shot....they were shot 30kmiles ago ..... should i be able to just buy new 1ton drums and shoes and be fine? im probably going to get new wheel cycinders at the same time...is there any advantage to stepping up to 1ton cylinders?

Bob, did you buy the wagner 3inch shoes?

thanks guys

[BobS]

my drums are completly shot....they were shot 30kmiles ago ..... should i be able to just buy new 1ton drums and shoes and be fine? im probably going to get new wheel cycinders at the same time...is there any advantage to stepping up to 1ton cylinders?

Bob, did you buy the wagner 3inch shoes?

thanks guys

I can't find the receipt but I believe they were plain old Carquest's better grade shoes.

[manyholes]

for what your gonna drop into it for new drums, hardware, shoes. why not look at doing a disc conversion. might be able to find a newer rear with discs to drop in plus pads. i was in a hurry to get mine on the road when i did the brakes or i would of sourced out a disc rear, seen them go for 700-900 around alberta for the dana's cause most stuff is AAM now i think

[ahale2772]

Yeah that's a good point, wish something just swapped in tho, hard to find a nice HD axle with 3.07s

[oldestof11]

Get 1 ton shoes, either 3/4 or 1 ton drums for a CUMMINS truck (Gasser 3/4 had a true 2.5" drum from what the parts guy told me), and get new 3/4 ton wheel cylinders. Bigger grabbing force with a slightly smaller bore equals a quick braking force.

[Ironforger]

Get 1 ton shoes, either 3/4 or 1 ton drums for a CUMMINS truck (Gasser 3/4 had a true 2.5" drum from what the parts guy told me), and get new 3/4 ton wheel cylinders. Bigger grabbing force with a slightly smaller bore equals a quick braking force.

I just did the 1 ton upgrade yesterday. Removed the awl accumulator, Cut my existing drums, installed 3" shoes and installed the 1 ton 1 1/8" bore wheel cylinders. My pedal travels way to far before I get braking force. Not road safe. Not completely sure yet, but I'm not ruling out if the larger wheel cyl bore is the culprit. Installed ALL new hardware/springs/adjuster/brake lines etc. I've got the adjusters up tight just touching the drums, but I'm also not ruling out larger inside diameter since I got drums cut because even though I got the starwheels adusted up tight, could it be = more wheel cyl piston travel before shoe to drum contact/brake force? I have a motive power bleeder so I'm doubting it's airbound, but does anyone know if I should bench bleed the master c yl since I had the whole system open & replaced ALL brake lines?

[ellis93]

Its got to be air causing your problem if the back brakes are adjusted up close. I did the same upgrade and my pedal moves about a 1/2" before you're slowing down.
Mine has been done for awhile and I've not had my rotors warp up from over heating from the rears not having the proper braking force.
I posted about doing this upgrade before I did mine and I believe that Mr BobS said something about another person that had a problem with the rotors warping.
I look at it like this, what's different between the 1ton and 3/4 trucks. The front adapters and the rear shoes and cylinders? Are the masters the same? I've looked at them and I've not seen and diff between the masters, but then again I've not worked on many because they are few and far in between

[ahale2772]

hows your ebrake Ironforger? If it feels like its not grabbing the whole way then Ellis is right, your shoes are probably adjusted way out

Ive Got a 1ton Master on my truck and it stops as good as the 3/4 so im guessing there is no bore change there,not definitly sure tho.

I know the front calipers, brackets spindls and all that are different 3/4 vs 1ton

No one seems to want to cut brake dums around here any more, I could do it on my late but I dont have the broing bar bits needed

the parts truck I keep picking parts of of was a 90' 1ton, im starting to consider swapping to a disk d80 if drums are going to cost me and arm and a leg...

[BILTIT]

Here are some disc options, not sure if we have the D70 or D70HD?

http://diy4x.com/cart/index.php?route=p ... ry&path=37

[ahale2772]

thanks for the link, but no thatnks LOL, had one of those kits on my 14bolt chevy....after the 12th time that I was under the truck wacking the ebrake screw to release...ill never use those again

Im guessing those use stock hubs? I wonder why they dont use the brackets for the backing plate to secure the disk bracket.

[Ironforger]

Its got to be air causing your problem if the back brakes are adjusted up close. I did the same upgrade and my pedal moves about a 1/2" before you're slowing down.
Mine has been done for awhile and I've not had my rotors warp up from over heating from the rears not having the proper braking force.
I posted about doing this upgrade before I did mine and I believe that Mr BobS said something about another person that had a problem with the rotors warping.
I look at it like this, what's different between the 1ton and 3/4 trucks. The front adapters and the rear shoes and cylinders? Are the masters the same? I've looked at them and I've not seen and diff between the masters, but then again I've not worked on many because they are few and far in between

Ellis, did you cut your existing drums? Or did you get new ones?

[Ironforger]

hows your ebrake Ironforger? If it feels like its not grabbing the whole way then Ellis is right, your shoes are probably adjusted way out

Ive Got a 1ton Master on my truck and it stops as good as the 3/4 so im guessing there is no bore change there,not definitly sure tho.

I know the front calipers, brackets spindls and all that are different 3/4 vs 1ton

No one seems to want to cut brake dums around here any more, I could do it on my late but I dont have the broing bar bits needed

the parts truck I keep picking parts of of was a 90' 1ton, im starting to consider swapping to a disk d80 if drums are going to cost me and arm and a leg...

E brake seems fine. It seems to grab fairly early. So, I think I see your point - ebrake travel should be a good indicator of how far the shoes are moving before contacting the drum? hence how far do the wheel cyl pistons travel before shoes contact drum? Or wait, update just had a revelation from my old school drum brake days. If I engage the ebrake slightly then attempt to drive, it will prevent the shoes from returning the wheel cyl pistons, so the shoes should be right there - very little piston travel for brake engagement - only as a test to see if piston/shoe travel is my cluprit.

I will report my findings. Thanks for the brainstorming ideas.


Ps, the 1 ton and 3/4 ton do indeed both use the same master c yl.