Hydroboost or vacuum brakes

[MetalMulishaMarcus]

I'm sure this has been topic has been beaten to death but I want you're opinion and I wanna hear about the problems you have/had with hydroboost.

I have vacuum brakes right now and I feel like they are not up to par with my 1 ton axles. My rear 14 bolt has disk brakes on it. I've upgraded the booster/master to a 1 ton set up and I replaced the stock distribution block to a disk/disk one but I feel like it's lacking. It stops but I get a soft spongy pedal randomly. I know I can add an adjustable proportion valve to make things better.

I wanna convert to hydroboost but I've read about people having problems or getting leaks and it scares me that its not reliable. I also have hydro assist so I feel like that might mess with a few things as well. I don't wanna lose brakes and/or steering if something goes wrong. I also want to keep my mechanical clutch, is that even possible? I don't want to have to put in a hydraulic clutch (I know it would be better).

So what would you do, keep the vacuum brakes or convert to hydroboost. I've done a lot of research about hydroboost but feel I'm still clueless.

 

[Hogback Fabrication]

If you have vacuum brakes, you're not using a 1 ton booster. All 1 tons got hydroboost. The vacuum booster doesn't have the beans to push the actual 1 ton master cylinder.

Hydroboost uses the same pump to run the power brakes and power steering, so if you're braking and steering at the same time you'll have less power for each. Vacuum brakes let your power steering pump run only the steering.

However, hydroboost makes significantly more pressure (and braking power) and it is matched to the axles (other than the discs in the back).

 

[MetalMulishaMarcus]

If you have vacuum brakes, you're not using a 1 ton booster. All 1 tons got hydroboost. The vacuum booster doesn't have the beans to push the actual 1 ton master cylinder.

Hydroboost uses the same pump to run the power brakes and power steering, so if you're braking and steering at the same time you'll have less power for each. Vacuum brakes let your power steering pump run only the steering.

However, hydroboost makes significantly more pressure (and braking power) and it is matched to the axles (other than the discs in the back).

That's good to know, I guess i bought something I thought was for a 1 ton.

How does a bigger hydro assist ram affect a hydroboost unit? I believe my ram is 2 inches.

 

[obijuank5]

Hydroboost is reliable as hell. Ryan's k30 is hydroboost with full hydro and no issues. It is a psc system.

The braking performance by itself is significant.

 

[MetalMulishaMarcus]

Hydroboost is reliable as hell. Ryan's k30 is hydroboost with full hydro and no issues. It is a psc system.

The braking performance by itself is significant.

That's good to know. I really think I should put in hydroboost.

 

[ChrisPerry]

If you have vacuum brakes, you're not using a 1 ton booster. All 1 tons got hydroboost. The vacuum booster doesn't have the beans to push the actual 1 ton master cylinder.

Hydroboost uses the same pump to run the power brakes and power steering, so if you're braking and steering at the same time you'll have less power for each. Vacuum brakes let your power steering pump run only the steering.

However, hydroboost makes significantly more pressure (and braking power) and it is matched to the axles (other than the discs in the back).

My master cylinder and booster is supposed to be from a 78 k30. At least thats what Rock Auto and Napa claim. Stop my truck fine. Only issue is the master cylinder starts leaking every year at BB.......

 

[MetalMulishaMarcus]

My master cylinder and booster is supposed to be from a 78 k30. At least thats what Rock Auto and Napa claim. Stop my truck fine. Only issue is the master cylinder starts leaking every year at BB.......

Ok what else did you do to it? Or did you only swap out the master and the booster?

 

[ChrisPerry]

Booster and master, no prop valve, and good disc brake pads front and rear.

 

[diesel4me]

Hydroboost is reliable as hell. Ryan's k30 is hydroboost with full hydro and no issues. It is a psc system.

The braking performance by itself is significant.

I agree WHEN IT WORKS it works great...

One thing that sucks though,is if you lose a P/S belt,go thru a deep puddle,or a hose fails,you not only lose the power steering,but all assist to the brakes as well....

This leads me to wonder why they trust this system on a 1 ton truck that is often heavily loaded..there is plenty of room for a larger vacuum booster ,I do not see why gas powered 1 ton trucks had to get hydroboost..

My '82 K2500 is a dangerous thing to drive now thanks to a leaky P/S box pitman arm seal,if I let it run low it will not only smoke the P/S pump,but make it very likely to get in a crash because without any assist to the brakes,even standing up on the pedal barely slows it down--it is worse than manual brakes!..if it were a gas powered truck with a vacuum booster,I could still steer it,though the effort would be greatly increased--but at least it would still stop with power brakes..

I'd prefer a vacuum booster--hydroboost is just another PITA thing to deal with if you go to swap in a gas motor in place of a diesel or vice-versa too..true,they rarely "fail",but when they do,it'll cost you a lot of money to get power brakes back again..about double what a new master cylinder & vacuum booster would cost..twice as many hoses to fail,different P/S pump (and brackets maybe too ?)..

 

[K5wrench]

Hydroboost 4 sure.
I have two blazers.
One vac boost.
Other hydro boost.

Twice the stopping power with hydro.
I have never noticed steering issues while braking off road with hydroboost.

Only downside i have seen, in other rigs, with hydro;
Climbing a hill and stalling a stick shift jeep with hydro boost brakes.
We yelled at the guy NOT to let off the brakes.
He did, and without the engine running he tried to ease down in reverse.
Ended up rolling out of control backwards, all the way down truck hill is Hollister and into a tree totalling his heap.
Airlifted his passsengers away.
Never forget the look on his face as he realized he lost his brakes and began rolling backwards.

But that is a pretty rare example.
Just don't put yourself in that predicament.
Vac brakes would have had one, maybe two more boosts with a dead engine.

 

[Vombrown]

I agree WHEN IT WORKS it works great...

One thing that sucks though,is if you lose a P/S belt,go thru a deep puddle,or a hose fails,you not only lose the power steering,but all assist to the brakes as well....

This leads me to wonder why they trust this system on a 1 ton truck that is often heavily loaded..there is plenty of room for a larger vacuum booster ,I do not see why gas powered 1 ton trucks had to get hydroboost..

My '82 K2500 is a dangerous thing to drive now thanks to a leaky P/S box pitman arm seal,if I let it run low it will not only smoke the P/S pump,but make it very likely to get in a crash because without any assist to the brakes,even standing up on the pedal barely slows it down--it is worse than manual brakes!..if it were a gas powered truck with a vacuum booster,I could still steer it,though the effort would be greatly increased--but at least it would still stop with power brakes..

I'd prefer a vacuum booster--hydroboost is just another PITA thing to deal with if you go to swap in a gas motor in place of a diesel or vice-versa too..true,they rarely "fail",but when they do,it'll cost you a lot of money to get power brakes back again..about double what a new master cylinder & vacuum booster would cost..twice as many hoses to fail,different P/S pump (and brackets maybe too ?)..

I gotta disagree a little here. Those issues are common to any truck at any time. Belts break, hoses fail that's just a maintenance issue. Hydro boost is vastly superior reliability wise comparing apples to apples. I guess I've ran dozens of them at this point and the only issue I've ever had was a slower power steering action. It certainly applies exponentially more braking force to the calipers. My k30 will lock up 37's with zero issue in stock form.

 

[mrk5]

I've only known hydroboost brakes in the 2 trucks I've been wheeling since I got into this hobby 14 years ago and I've never had an issue with them. Worst incident was a failed power steering pump. It does make bleeding more difficult when adding hydro assist, at least it did for me. But I have a system down for that too.

 

[MetalMulishaMarcus]

I agree WHEN IT WORKS it works great...

One thing that sucks though,is if you lose a P/S belt,go thru a deep puddle,or a hose fails,you not only lose the power steering,but all assist to the brakes as well....

This leads me to wonder why they trust this system on a 1 ton truck that is often heavily loaded..there is plenty of room for a larger vacuum booster ,I do not see why gas powered 1 ton trucks had to get hydroboost..

My '82 K2500 is a dangerous thing to drive now thanks to a leaky P/S box pitman arm seal,if I let it run low it will not only smoke the P/S pump,but make it very likely to get in a crash because without any assist to the brakes,even standing up on the pedal barely slows it down--it is worse than manual brakes!..if it were a gas powered truck with a vacuum booster,I could still steer it,though the effort would be greatly increased--but at least it would still stop with power brakes..

I'd prefer a vacuum booster--hydroboost is just another PITA thing to deal with if you go to swap in a gas motor in place of a diesel or vice-versa too..true,they rarely "fail",but when they do,it'll cost you a lot of money to get power brakes back again..about double what a new master cylinder & vacuum booster would cost..twice as many hoses to fail,different P/S pump (and brackets maybe too ?)..

I'm glad you chimed in, I read you're thread about hydroboost and it made me think twice about it. That's why I posted this one asking what other people had problems and what they would do.
Thank you for you're input

 

[Rugby_7]

I was running a master and power booster from a 1974 3/4 ton and it stopped just fine. I have one tons with discs.
Due to my stupidity I have to replace both. I'm trying a power booster from a 1985 k20, Master from a 2000 Tahoe with a 5.3, and a 2001 s10 reservoir for hood clearance. From what others have said on Facebook it is supposed to be a great combo.

 

[diesel4me]

I gotta disagree a little here. Those issues are common to any truck at any time. Belts break, hoses fail that's just a maintenance issue. Hydro boost is vastly superior reliability wise comparing apples to apples. I guess I've ran dozens of them at this point and the only issue I've ever had was a slower power steering action. It certainly applies exponentially more braking force to the calipers. My k30 will lock up 37's with zero issue in stock form.

I wont argue its rare for hoses to fail ,but belts can at any time without warning,and slip if they get wet..
I agree the hydroboost does have superior power assist ,but when something as simple as going thru a deep puddle can make you lose both steering and power brakes ,even if only for a few short seconds,to me that isn't exactly safe setup!...

I had that happen one day going to a plowing job at a parking lot at my friends business--had the plow on the truck,(500+ lbs of dead weight up front)--roads were mostly just wet with slush on them--I went thru a deep puddle while cornering around a rotary circle,and the steering suddenly went stiff,I went to hit the brakes to slow it down and found myself standing on the pedal up off the seat,and the truck barely had any braking action--pedal was rock hard though!..

It was all I could do not to go into the ditch ,luckily I was able to downshift it and slow it down enough to maintain control..the steering was VERY hard with no power assist,even with it rolling,all the plow's weight certainly helped none..I tried dropping the blade to help slow it down too,that didn't do much to help though..

Ever since that day I've been leery of the hydroboost..seems to easy for it to be lost under certain driving conditions..they should have at least used double V-belts,or better yet,had a separate pump for the hydroboost..Off roading thru mud bogs and water crossings would likely be dangerous with hydroboost seeing how the belt can get wet easily and slip..(maybe later ones with serpentine belts are not as prone to this,my truck has only one v-belt)..

The power assist to my brakes suddenly was reduced quite a bit recently,why I have no clue,the power steering pump works OK for steering still,and far as I can tell no calipers,wheel cylinders,or rubber hoses are seizing up or clogged,and it loses no brake fluid..master cylinder was replaced last year too..hydroboost seems to be one of those things that either works perfect,or not good,or at all,in my experience..and most mechanics don't know much about it,they just "throw on a rebuilt unit" and hope that fixes it..

 

[MetalMulishaMarcus]

I was running a master and power booster from a 1974 3/4 ton and it stopped just fine. I have one tons with discs.
Due to my stupidity I have to replace both. I'm trying a power booster from a 1985 k20, Master from a 2000 Tahoe with a 5.3, and a 2001 s10 reservoir for hood clearance. From what others have said on Facebook it is supposed to be a great combo.

Please keep me updated on this because I'm putting in a 5.3 as well and I would like to see if this combo really works

 

[skunked]

you should have no problem with vacuum brakes, sounds like you have an issue with a random soft pedal that needs to be fixed before jumping the gun to hydro.

 

[K5wrench]

I wont argue its rare for hoses to fail ,but belts can at any time without warning,and slip if they get wet..
I agree the hydroboost does have superior power assist ,but when something as simple as going thru a deep puddle can make you lose both steering and power brakes ,even if only for a few short seconds,to me that isn't exactly safe setup!...

I had that happen one day going to a plowing job at a parking lot at my friends business--had the plow on the truck,(500+ lbs of dead weight up front)--roads were mostly just wet with slush on them--I went thru a deep puddle while cornering around a rotary circle,and the steering suddenly went stiff,I went to hit the brakes to slow it down and found myself standing on the pedal up off the seat,and the truck barely had any braking action--pedal was rock hard though!..

It was all I could do not to go into the ditch ,luckily I was able to downshift it and slow it down enough to maintain control..the steering was VERY hard with no power assist,even with it rolling,all the plow's weight certainly helped none..I tried dropping the blade to help slow it down too,that didn't do much to help though..

Ever since that day I've been leery of the hydroboost..seems to easy for it to be lost under certain driving conditions..they should have at least used double V-belts,or better yet,had a separate pump for the hydroboost..Off roading thru mud bogs and water crossings would likely be dangerous with hydroboost seeing how the belt can get wet easily and slip..(maybe later ones with serpentine belts are not as prone to this,my truck has only one v-belt)..

The power assist to my brakes suddenly was reduced quite a bit recently,why I have no clue,the power steering pump works OK for steering still,and far as I can tell no calipers,wheel cylinders,or rubber hoses are seizing up or clogged,and it loses no brake fluid..master cylinder was replaced last year too..hydroboost seems to be one of those things that either works perfect,or not good,or at all,in my experience..and most mechanics don't know much about it,they just "throw on a rebuilt unit" and hope that fixes it..

Proportioning valve?
If something happened to the rear brakes or even after being bled, the prop valve can stick, reducing flow to the rear and even front brakes.
I had to remove mine from the front cross member and reset it manually through the brake warning light switch hole.
You can diagnose it; if the front brakes bleed fine but nothing comes out of the rear=prop valve is triggered.
Light is supposed to come on the dash but with these old trucks a lot of times bulb is burnt out or someone disconnected the wire.
It's a place to look anyways.

 

[Rugby_7]

Please keep me updated on this because I'm putting in a 5.3 as well and I would like to see if this combo really works

Will do! I had knee surgery yesterday so might be a little while before I get to it.

 

[diesel4me]

Proportioning valve?
If something happened to the rear brakes or even after being bled, the prop valve can stick, reducing flow to the rear and even front brakes.
I had to remove mine from the front cross member and reset it manually through the brake warning light switch hole.
You can diagnose it; if the front brakes bleed fine but nothing comes out of the rear=prop valve is triggered.
Light is supposed to come on the dash but with these old trucks a lot of times bulb is burnt out or someone disconnected the wire.
It's a place to look anyways.

That might be a possibility--If I remember right,on this truck I never could get the brake warning light to shut off even after bleeding it and having excellent brakes,and full flow to the rear wheel cylinders..to pass inspection, you must have the light working,when they turn on the key without starting the engine..so I unplugged the wire on the PV to keep it from staying on once they started it up..still works when you apply the e-brake too..

They "test" your brake lines here by stomping on the brake pedal hard enough to pop new ones too,maybe that messed something up in the hydroboost,but it didn't start feeling like it lost some of the power assist until a few months ago--inspection time was in June..
I'm wondering if the leaking pitman shaft seal might be reducing the pressure to the hydroboost unit..but that didn't start leaking until a few weeks ago too..(and so far its not a "gusher",just drippage)..