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    Guest Message by DevFuse
     

    Photo

    Wedge Brakes



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    16 replies to this topic

    #1 OFFLINE   doublemmacks

    doublemmacks

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    • Model:B-421 "S"
    • Year:1963

    Posted 06 February 2010 - 11:41 PM

    Hey Everybody,
    I just bought a truck that has wedge type brakes on th rear axels. I was wondering if anybody has messed with them before and also how reliable are they and how well do they work? My truck has four brake pods on each rear axel,(two on each side). If anyone has any advice, I'd appreciate it.Thanks,
    Daniel

    #2 OFFLINE   Rob

    Rob

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    • Model:A-40H, B-61T, B-61ST, B-67ST, B-61S, RL-797LST, RL-797LST, RL-755L, R795, R612ST
    • Year:1951 1957 1958 1962 1964 1973 1974 1978 1977 1980

    Posted 06 February 2010 - 11:59 PM

    Hey Everybody,
    I just bought a truck that has wedge type brakes on th rear axels. I was wondering if anybody has messed with them before and also how reliable are they and how well do they work? My truck has four brake pods on each rear axel,(two on each side). If anyone has any advice, I'd appreciate it.Thanks,
    Daniel


    Most will say they are garbage and they are probably right. I have a 73 RL797L with them on front and rear and they work perfect. Get a book and take the hubs apart making sure the adjusters are greased properly and not frozen, then adjust them as they should be and they will work well for you.

    Rob

    Going through life knowing considerably more about nothing than the next person.

    ParadeRain.gif
    Raining on your parade


    #3 OFFLINE   David

    David

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    Posted 07 February 2010 - 12:53 AM

    Had a tractor with wedge brakes once. Just had to be sure it had a trailer behind it with good enough brakes to stop the whole rig!

    #4 OFFLINE   doublemmacks

    doublemmacks

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    • Year:1963

    Posted 07 February 2010 - 02:07 PM

    Had a tractor with wedge brakes once. Just had to be sure it had a trailer behind it with good enough brakes to stop the whole rig!

    Thanks Rob & David for your input. We'll be going through he whole truck and was wondering if they would need to be replaced with something better. Thanks, Daniel

    #5 OFFLINE   theakerstwo

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    Posted 07 February 2010 - 10:30 PM

    Thanks Rob & David for your input. We'll be going through he whole truck and was wondering if they would need to be replaced with something better. Thanks, Daniel

    http://www.axletech....andard/mm4r.pdf This is a manual you can read some if you go into them. If you do them right and make sure the adjucters are not bad and then clean them and use the grease that rockwell makes with new seals on the plungers you will be able to use them for many miles. Dont use any grease unless it is a water proof grease. Make sure the drums are good and smooth and no grooves in drums or on the shoes. Adjust them up be for you mave the truck If you dont do this you sre only playing with your self.They dont have a lot of travel so get them up almost draging to start with.They in most cases are self adjusting.
    glenn akers

    #6 OFFLINE   doublemmacks

    doublemmacks

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    Posted 08 February 2010 - 07:27 PM

    http://www.axletech.com/service_manuals/pdf/standard/mm4r.pdf This is a manual you can read some if you go into them. If you do them right and make sure the adjucters are not bad and then clean them and use the grease that rockwell makes with new seals on the plungers you will be able to use them for many miles. Dont use any grease unless it is a water proof grease. Make sure the drums are good and smooth and no grooves in drums or on the shoes. Adjust them up be for you mave the truck If you dont do this you sre only playing with your self.They dont have a lot of travel so get them up almost draging to start with.They in most cases are self adjusting.

    Theakerstwo, Thanks for your reply, that website should help us a lot. Thanks, Daniel

    #7 OFFLINE   Packer82935

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    • Year:1958, 1959,1948, 1942,1963, 1947,1963

    Posted 08 February 2010 - 10:21 PM

    As one of the BMT Guru's stated once:

    "If you push on the brakes and you stop - - - You don't have wedge brakes"

    I still laugh about that!!!!!

    Most funny!

    Packer
    Keep a clutchin'

    #8 OFFLINE   Rob

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    • Model:A-40H, B-61T, B-61ST, B-67ST, B-61S, RL-797LST, RL-797LST, RL-755L, R795, R612ST
    • Year:1951 1957 1958 1962 1964 1973 1974 1978 1977 1980

    Posted 08 February 2010 - 10:36 PM

    As one of the BMT Guru's stated once:

    "If you push on the brakes and you stop - - - You don't have wedge brakes"

    I still laugh about that!!!!!

    Most funny!

    Packer


    That RL of mine you gotta be careful when stepping on the brake pedal unless you like the taste of laminate glass because a lighter man would surely kiss the windshield if they were to plant the pedal. The combination of my bloated carcass and steering wheel brake belly keeps me from doing it. I've had all the wheels and drums off and everything is new inside the hubs and is adjusted as per the manual. I guess as Glenn said they'll serve a long time if maintained properly but are a nightmare if not.

    Rob

    Going through life knowing considerably more about nothing than the next person.

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    #9 OFFLINE   bigen

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    Posted 09 February 2010 - 03:59 AM

    i drove a three live axle dm it was a red bird concrete truck that bill revel put a dump bed on 20 ft. shot rock box 37,000 empty and clean. he built 3 of them, 237,18 speed quadroplex, my sholder hurts still aafter 20 years. it had wedge brakes it would slide every wheel with 40 ton on it,gvw around 120,000. they where great. but the machanics there did not know how to work on the wedge brakes,or didn't want to spend the time, so in a short time, hauling that kind of loads, they didn't last long. if you went from 4th to 3rd in the main box to hard, they would break the input shaft on the front axle. between that and the wedge brakes they where parted out.

    #10 OFFLINE   bigen

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    Posted 09 February 2010 - 04:02 AM

    wish i had pictures they where so cool, when i was in my twenty's
    it would make for a very long day in my 40's

    #11 OFFLINE   bigen

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    Posted 09 February 2010 - 04:12 AM

    i have never seen cam brakes that would do that!

    #12 OFFLINE   joes mack

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    Posted 09 February 2010 - 03:18 PM

    this might be a stupid question but what is the diff about the wedge brakes? i got a cut off for extra parts for my truck and the cams and shoes are difrent than the ones on my truck the cams on the cutoff look like Z's and the shoes have a flat spot on them instead of rollers. are these wedge brakes? joe

    #13 OFFLINE   ThaddeusW

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    Posted 09 February 2010 - 06:38 PM

    As one of the BMT Guru's stated once:

    "If you push on the brakes and you stop - - - You don't have wedge brakes"

    I still laugh about that!!!!!

    Most funny!

    Packer


    I remember: If the truck does not stop you have wedge brakes. If it stops you may or may not have wedge brakes.
    -Thad
    What America needs is less bull and more Bulldog!

    #14 OFFLINE   theakerstwo

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    Posted 09 February 2010 - 08:42 PM

    Old joke of mine. Wedge brakes never wear out. Why? The shoes never touch the drums. Well that is almost true cause like Rob said if they are done the right way they can be a good brake. They do not require much voluminof air because of the small cans on them.But when they stop adjusting then get them down and repair the adjusters.CF used them big time on tractors and trailers.
    glenn akers

    #15 OFFLINE   David

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    Posted 10 February 2010 - 12:29 AM

    this might be a stupid question but what is the diff about the wedge brakes? i got a cut off for extra parts for my truck and the cams and shoes are difrent than the ones on my truck the cams on the cutoff look like Z's and the shoes have a flat spot on them instead of rollers. are these wedge brakes? joe


    No. I've heard them called flat cams or z cams. Wedge brakes have a wedge (instead of the cam) located between the shoes.

    #16 OFFLINE   fjh

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    Posted 10 February 2010 - 12:39 AM

    Old joke of mine. Wedge brakes never wear out. Why? The shoes never touch the drums. Well that is almost true cause like Rob said if they are done the right way they can be a good brake. They do not require much voluminof air because of the small cans on them.But when they stop adjusting then get them down and repair the adjusters.CF used them big time on tractors and trailers.

    Keep us guys employed getting them backed off to get the wheels off anyway Glenn! Posted Image

    !

    #17 OFFLINE   doublemmacks

    doublemmacks

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    Posted 10 February 2010 - 07:18 PM

    Keep us guys employed getting them backed off to get the wheels off anyway Glenn! Posted Image

    !

    Thanks everybody that replied to my question. Sorry tht I didn't get back to you all earlier but I had some prblems with my computer. Thanks Again for all the help. Daniel




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