What to look for in drivetrain

[banman]

Originally Posted by Booyah45828

I'll agree to that, if it has lucas/girling brakes, run away. I don't care if it's free. I'd probably avoid anything full sized with hydraulic brakes
snip...

Don't hide, explain.

I've got ABS hydraulic 4 wheel disc (bendix) on my bus. In the process of replacing the rusted lines with NiCu tubing.

And it's got hydroboost like a p'up truck would.

[Jolly Roger bus 223]

i know abs and hydraulic brakes and have had to decipher and work on some lucas/girling stuff.
with abs or hydraulic brakes you have to get all of the air out of the fluid for them to work properly.
with the lucas brake system it added air into the system to push the hydraulic fluid where it needded to be.
air in steel brake lines create moisture so the brake fluid set at each brake drum or caliper and was compressed by air that created moisture that contaminated the fluid while much less the air bubbles in the brake fluid that is already contaminated with water and your trying to stop something with 3 different compression ratio fluids in the mix?
leaves air in the steel lines that rots and rust the lines from the inside and normally outside at the same time.
lots more.
hope this enough for you to steer away from any lucas/girling stuff. was an idea of the time but a little age showed its faults constant nightmare if you plan on stopping.
thats my opinion
good luck

[Booyah45828]

Originally Posted by banman

Don't hide, explain.

I've got ABS hydraulic 4 wheel disc (bendix) on my bus. In the process of replacing the rusted lines with NiCu tubing.

And it's got hydroboost like a p'up truck would.

I have experience with both, and I'd prefer air brakes on anything they're available on. They seem to have more stopping power, less issues, and are easier to diagnose issues when they do occur. Granted, I don't experience arctic freeze conditions like those up north, so maybe my opinion would change if I did.

I'm not saying hydraulic brakes can't work, I'm just saying air brakes seem to work better and are less problematic.

Good call on the NiCu tubing. It's way easier to bend and flare then steel. Get the stuff from sur&r, it flares and bends better then the stuff from ags imo.

[banman]

Originally Posted by Booyah45828

I have experience with both, and I'd prefer air brakes on anything they're available on. They seem to have more stopping power, less issues, and are easier to diagnose issues when they do occur. Granted, I don't experience arctic freeze conditions like those up north, so maybe my opinion would change if I did.

I'm not saying hydraulic brakes can't work, I'm just saying air brakes seem to work better and are less problematic.

Good call on the NiCu tubing. It's way easier to bend and flare then steel. Get the stuff from sur&r, it flares and bends better then the stuff from ags imo.

Interesting. I'm coming from an aircraft maintenance background and on the personal side playing with my ol' cars/trucks...

All of the aircraft I'm familiar with have hydraulic brakes -- but that could simply be because there's already an hydraulic system for the landing gears and flt controls. Hmmm, Bleed air from the turbines is used to power the hvac...

Anyway, hydraulic brakes is what I'm more familiar with so I guess I'm lucky there. I think/suspect a partially leaking air-brake system will still give you some decent braking action while a hydraulic fluid leak is more apt to give you nothing...

For the amazon dwellers -- The Stop Shop has the best price on NiCu tubing anywhere I've seen. Be cautious of prices any lower NOT actually being the real deal. NiCu tubing should be screen printed every foot or so "DOT approved J**** (# varies by size I believe...)

[Booyah45828]

Air brakes have a mechanical fail safe, where if you lose or lack air pressure, you're not going anywhere.

Lucas girling brakes tried to accomplish the same thing, but with hydraulic fluid, brake fluid, electric back up motors, and a valve or two. This turned something that should be simple, into something that more represents a rube goldberg contraption.

Hydraulic brakes use either a hydroboost or vacuum booster. Lose either and your brakes lost a lot of performance. Same with getting a brake fluid leak. No such issues with air brakes. You can leak air like a sieve and still stop.

Yes, some of the components in an air brake system can make your head spin. But get to know how they operate and they become quite simple.

Aircraft don't use air brakes, too much of a chance of freezing up I guess.

[banman]

Originally Posted by Booyah45828

Air brakes have a mechanical fail safe, where if you lose or lack air pressure, you're not going anywhere.
I remember some of the bigger trucks I occasionally used in the army had air brakes -- You had to have enough system pressure to release the parking brake. Is that what you mean?


Hydraulic brakes use either a hydroboost or vacuum booster. Lose either and your brakes lost a lot of performance. Same with getting a brake fluid leak. No such issues with air brakes. You can leak air like a sieve and still stop.
Because the air compressor on the engine is making more pressure than the average leak...
Yes, some of the components in an air brake system can make your head spin. But get to know how they operate and they become quite simple.

Aircraft don't use air brakes, too much of a chance of freezing up I guess.

Anything that uses "air" on any aircraft I've worked uses nitrogen gas instead. From a filtered source, no moisture, so no corrosion or freezing issues. The tires are inflated with nitrogen. The struts for the landing gear get filled with hydraulic fluid and nitrogen. Just bigger versions of the ABS accumulator's like you see on a modern car. That (automotive) cartridge is also filled with nitrogen.