11 inch drums fix or Disk brake conversion?

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Old Guy Bill

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You did measure backlash in the gear set before disassembly??
Depending on what the gears look like you can improve the backlash somewhat.
 

Ricko1966

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It takes a larger diameter disc than drum to have equal braking ability. There is more surface area on a shoe and drum than there is on a pad and disc.
 
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ali_c20

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It takes a larger diameter disc than drum to have equal braking ability. There is more surface area on a shoe and drum than there is on a pad and disc.
Most drum brakes are self energizing too so they multiply the brake force.
Heavy duty trucks still use drum brakes. In Europe a transition has started and the many new trucks and trailers are made with disk brakes all around.
 

rydog

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You did measure backlash in the gear set before disassembly??
Depending on what the gears look like you can improve the backlash somewhat.
I didn't I can't find much in Haynes manual about it. I guess maybe because they are so universal they don't put info in the car specific manual
 

Ricko1966

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Nm
 

rydog

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You did measure backlash in the gear set before disassembly??
Depending on what the gears look like you can improve the backlash somewhat.
I measured it when I got it back together and it's 0.013 so I guess that where the clunking noise is coming from.

I can't find a good write up or video on how to adjust it on the 14 bolt semi float. I find plenty on the full float.

Seems like I would maybe need to buy shims?
 

rydog

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Hey I cannot get the brakes to bleed in this thing.

I keep reading about the proportioning valve but if when the pedal is pressed I get a descent flow of fluid through the bleeder it's not that right?

I blocked off the fronts and the pedal feels great so if must be something with front right?

I'm tempted to try putting on my old caliper.

I've replaced the master cylinder, rotors and calipers, drums and wheel cylinders.
 
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Heavy duty trucks still use drum brakes. In Europe a transition has started and the many new trucks and trailers are made with disk brakes all around.
Its been here for a good bit, especially the fronts. Dad's Freightliner had em on every wheel end. Trailer too. It was a newer truck and had 300,000 on it when he retired last year....still had the factory brakes.
 

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