Hi, all. I recently saw this thread (https://www.ford-trucks.com/forums/8...sion-done.html) on here, and it got me thinking about a few things. I have hydroboost parts from a 2002 Chevy 3500 (the PS pump went with the dead duramax engine i sold), and a failed braking system (possibly the vacuum pump) on my ford truck. eventually, I'm going to swap the engine and body into the 2002 chevy frame, and go ham on the customization, but I need the ford working in the meantime to pick up larger parts. I'm trying to do this without spending a bunch of cash where I dont need to. I'm already spending too much on fuel return rails and an upgraded 7.3 glow plug set up.

first thing I got to wondering, is does the stock f350 PS pump run enough pressure to work both a hydroboost system AND the steering at the same time? If not, what would the difference be with the F450 pump? and where can I source it? I didnt have luck checking Autozone or Oreillys web pages for anything hydroboost specific.

Second, I have the chevy hydroboost MC and Booster, and the pedal as well. I was going to temporarily use them on my ford frame, and just transfer the system to the chevy frame they came off of when I could. I read in that post that the drum brake rear end of the ford would have problems with the chevy MC. Is anyone able to elaborate on that? and is there anything I can do on a budget to eliminate this problem? I already plan to replace all my steel line with new line, and replace all my rubber lines with braided steel lines, just to ensure no problems with the upgraded pressures.

and third, does anyone have suggestions for how to route the hoses in this set up? I can have some custom hoses made for not alot of money (courtesy of my work), but I'm not really sure the order the fluid needs to flow on a hydroboost system. And i'm trying to avoid the problem with my last hydroboost truck where i lost power steering whenever I was using the brakes.

Thanks for helping an amateur customizer!

 

If the vacuum pump bit the dust just replace it, of everything you listed that is far and away the lowest cost option, even for the short term...

 

The cheapest I've been able to find a replacement vacuum pump is $120 plus tax. I still have to replace all my lines because of a different issue (they constantly develop a spongy pedal), so that cost is the same either way. I figured if my PS pump would work, or if I can source a PS pump that will work and bolt right up, then using the pedal, MC, and booster that I have from the chevy could be a cheaper option. I just dont know what I need to look for for the PS pump, and I dont know if the chevy MC would work with the ford drum rear brakes.

but if 120 is the cheapest way, I will for sure go that way.

 

I just want this to happen. I am no help. Please take pictures.

 

so i found a PS pump that will do exactly what i need at oreillys. I have to call them and find out my price for corporate pricing (my work gets discounts thru them). Now all that I need to figure out is do i need to run my factory ford MC? or will the chevy MC that came with the hydroboost work? Thats the main question at this point. and so far, its cheaper than replacing my vacuum pump and continuing with my weak brakes.

 

You have a long road to go there with chevy parts on a Ford. First off, the pumps are the same, it's just the reservoir on the hydroboost application has a extra hose fitting for an extra fluid return from the hydroboost unit. You can use your original pump if you want to swap out the reservoir. Or just get the whole pump like you mentioned.

The pedal assembly mounts in the cab on the firewall. It's not going to fit, but if you have some fabrication skills you may be able to make it fit. I do remember on the Fords, even the pedal arm between the vacuum boost and the hydroboost are different, there are different pedal ratios between the two. If you want all the factory engineering, the best thing to do is get the pedal assembly and pedal arm from a f450 and bolt it in place.

 

I actually have the pedal assembly from the chevy. that would solve the issue of the pedal with the booster, right? even if i have to drill a few holes, if I make a good template, It should work pretty good, i would think.

The last remaining question I have is actually which master cylinder needs used? I noticed the specs between the ford and the chevy masters are different, with the chevy having a 1/4" larger bore on it, but its also set up for all wheel disc brakes. The ford is a master for front disc, rear drum. The mounting bolts appear (currently) to be close, if not the same, for mounting the master to the booster. and from reading some of the posts like the one i mentioned in my first post here, my understanding is that the proportioning valve is where the problem crops up.

 

The Ford f450 master was for 4 wheel discs also. The f250/350 masters were disc/drum. If you can get it to fit, you can put any master you want on it.

The brake system works much like a hydraulic jack. A small hydraulic jack has the same piston to pump the fluid as a larger hydraulic jack, but it takes much fewer pumps to pump the smaller jack up. But it has less power behind it. The larger hydraulic jack takes many more pumps to jack it up, but it is much more powerful, much like a gear ratio would work. If you use a master with a larger bore, the brakes will work with much less pedal travel, but will not have the same pressure. But if you raise the connection point on the brake pedal arm, then you can gain that advantage you lost back. It's all in the design. You can try it and see how it works.

 

You should replace the vacuum pump, they can be had about 90 bucks, you are opening a huge can of worms trying to put the chevy parts in you truck.

 

I swapped in a chevy 2500 hydroboost and MC on my bullnose. Pretty straight forward. Or at least it felt straight forward compared to everything else I was doing to the truck. I would recommend it if you have the parts handy.

Pretty easy swap. I used the stock pedals so my brakes are sensitive right now but I can always shift the pedal post(?) The mc connects to if I wan tot change it