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Has anyone looked at a medium duty Freightliner ,hydro brakes.We use a hydro boost brake system with a electric motor for back up.If anyone is interested I'll check on part numbers and cost.
 

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Sounds like good information. Part numbers, reference years and model numbers, pictures, and possibly a diagram of how it works would be a real plus. Then I can index it in the FAQ for future reference.
 

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Sounds expensive.

A factory vacuum brake booster with an electric vacuum pump would probably be a lot cheaper.
 

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I'm interested..

True, likely more expensive than if you use the vacuum booster you already have and just need a pump, but if you're going to be converting to hydroboost anyway.. Might not be too large a kick in bottom line.

What I'm looking at is that you've got boost even when the engine fails, and more than just one shot of it..
 

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I think the accumulator in the hydroboost gives you 2-3 assisted brake jabs without hydraulic pressure. If you can't stop the pickup you're driving without power assisted brakes in an emergency you shouldn't be driving it.
 

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I think the accumulator in the hydroboost gives you 2-3 assisted brake jabs without hydraulic pressure. If you can't stop the pickup you're driving without power assisted brakes in an emergency you shouldn't be driving it.
Agreed, but if I've found it best to avoid the need to use such skills where I can.. :eek:
 

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An electric vacuum pump with a vac reservoir would give you more than 2-3 pumps.

I know HB systems work, I'm just not a big fan of all the added complexity and am not easily convinced to switch over (don't see enough positives)
 

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HB has been really reliable for me. It's capable of higher braking pressures than vacuum, it's a cleaner package than a big booster and it's dirt cheap.

When converting an old Ford to power brakes I used to search all over for power brake setups to find most of them were bad and rebuilds were outrageous. Now I spend an hour at U-pullit getting the complete HB out and they charge $8 for it. Takes me a few hours to machine an adapter plate and change the rod length for a bolt in.
 

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there is no added complexity. one extra pressure line and one extra return line. already have the pump for the power steering, so might as well use it. i've never had any problems out of hydroboost. i've seen one where they used a pump from a tommylift as a backup also, but he was running full hydro steer so it was definately a need for it.
 
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