chrisp2493
Always Modding
- Joined
- Oct 30, 2016
- Posts
- 3,006
- Reaction score
- 1,870
- Location
- Warren, OH
- Ram Year
- 2003
- Engine
- 392 Hemi
There are some old threads on other forums about this, but figured I’d throw one up for people who haven’t heard of it. This isn’t my idea, many people have done it, but I took lots of pictures while I did mine. Here is what I used
I got a hydrobooster off a 3rd gen Cummings truck. I got it for $60 at a local wrecking yard. Unfortunately they cut off the lines instead of unscrewing the fittings, so I sourced them elsewhere
I found a guy parting out another Cummings truck, so I bought the 3 main hoses and fittings from him for $80. There are 3 lines, 2 bough pressure lines going to the power steering rack and to the power steering pump. And 1 low pressure return line, it’s just a 3/8” rubber tube. You can get these lines made at a store like NAPA or somewhere similar, but I needed up having a hard time dealing with the guy at the counter and decided to just buy them from the cummins truck. All the hoses fit as far as the length for me.
To remove the vacuum booster, unplug the electrical connector on the brake fluid reservoir. This plug will go straight into it, no change needed. Disconnect the two brake lines, these will also screw into the new hydrobooster with some slight stretching.
Disconnect the air vacuum hose. The manifold will need plugged or you’ll have a vacuum leak.
Inside the truck by the brake peddle, there is a safety clip that holds the pushrod to the brake peddle. Remove that and the peddle will swing free. Then there are 4 15mm nuts to remove and the booster will be free. It helps to have a long ratchet extension and a socket knuckle attachment. Then the booster will pull right off the truck
Untitled by Chris Pearce, on Flickr
The booster will fit right into the old holes, everything lines up. Make sure when you put the booster in, the pushrod is on the right side of the peddle. I had to take the booster back out and line the pushrod up because it got caught on the opposite side of the peddle arm and there wasn’t enough room to wiggle it over. It helps to have a second pair of hands to line it up easily. One small issue I ran into was after it was all tightened up, the peddle was about 1/16” of an inch further away and the brake switch wasn’t shutting off the brake lights correctly. I don’t know if I accidentally bent the switch bracket alittle, or if the pushrod is slightly longer. I just added a small spacers to the peddle to push the brake switch in alittle further to work correctly. Again, not sure if that is the case for everyone. In my case, I just drilled a 5/16" hole and put a 1/4" bolt and nut through it, That will hold the brake switch in the off position pretty well
Untitled by Chris Pearce, on Flickr
Now for the lines. The return line needs to be T’ed into the power steering cooler line that goes from the cooler to the reservoir. The cooler line is 5/8” inside diameter, the return line for the booster is 3/8” ID. I pieced these parts together at NAPA in a pinch, cost me over $30 for the Parts. You might find a pre-made T cheaper somewhere else. It’s a low pressure line so barbed ends and hose clamps work fine.
The top line coming off the booster goes to the power steering pump. To retain the power steering pressure sensor, you have to splice into the factory hard line. I cut the factory line about 1” above the sensor and installed a 3/8” flared union. It’s is NOT a compression fitting, it’s actually flared. This is a high pressure line
I cut the booster line to fit, flared that line and screwed it together
The bottom line off the booster goes to the power steering rack. It screws into the lower hole in the power steering rack. The Cummings line fit right in for me, that was pretty simple.
It was recommended to me to use ATF 4 transmission fluid in the power steering rack after this changeover. I’m not really sure why, I think it has to do with how it holds up in the winter and cold temperatures. I actually would love some more info on that, but that’s what I used. And just standard brake fluid in the lines. You will have to bleed the brakes after this.
I’ve only driven a few times since the switch, but the brakes are WAY more solid then the air system. You barely push the peddle to brake now. It feels rock solid. I haven’t had the chance to really test them out. Now in case you are wondering, if for whatever reason your truck stalls, you will STILL HAVE BRAKES!! I think there is a check valve in the system that keeps some pressure for a few brake applications. When I was tuning my new cam, I had the truck stall will driving a few times, so I can personally attest to them still working when the truck is dead.
I’m am really pleased with the outcome. On top of solid brakes, there is so much more room in the engine bay. It’s very easy to reach the back valve covers and spark plugs now, it was worth it just for that. It only cost me about $200 all said and done
I got a hydrobooster off a 3rd gen Cummings truck. I got it for $60 at a local wrecking yard. Unfortunately they cut off the lines instead of unscrewing the fittings, so I sourced them elsewhere
I found a guy parting out another Cummings truck, so I bought the 3 main hoses and fittings from him for $80. There are 3 lines, 2 bough pressure lines going to the power steering rack and to the power steering pump. And 1 low pressure return line, it’s just a 3/8” rubber tube. You can get these lines made at a store like NAPA or somewhere similar, but I needed up having a hard time dealing with the guy at the counter and decided to just buy them from the cummins truck. All the hoses fit as far as the length for me.
To remove the vacuum booster, unplug the electrical connector on the brake fluid reservoir. This plug will go straight into it, no change needed. Disconnect the two brake lines, these will also screw into the new hydrobooster with some slight stretching.
Disconnect the air vacuum hose. The manifold will need plugged or you’ll have a vacuum leak.
Inside the truck by the brake peddle, there is a safety clip that holds the pushrod to the brake peddle. Remove that and the peddle will swing free. Then there are 4 15mm nuts to remove and the booster will be free. It helps to have a long ratchet extension and a socket knuckle attachment. Then the booster will pull right off the truck
Untitled by Chris Pearce, on Flickr
The booster will fit right into the old holes, everything lines up. Make sure when you put the booster in, the pushrod is on the right side of the peddle. I had to take the booster back out and line the pushrod up because it got caught on the opposite side of the peddle arm and there wasn’t enough room to wiggle it over. It helps to have a second pair of hands to line it up easily. One small issue I ran into was after it was all tightened up, the peddle was about 1/16” of an inch further away and the brake switch wasn’t shutting off the brake lights correctly. I don’t know if I accidentally bent the switch bracket alittle, or if the pushrod is slightly longer. I just added a small spacers to the peddle to push the brake switch in alittle further to work correctly. Again, not sure if that is the case for everyone. In my case, I just drilled a 5/16" hole and put a 1/4" bolt and nut through it, That will hold the brake switch in the off position pretty well
Untitled by Chris Pearce, on Flickr
Now for the lines. The return line needs to be T’ed into the power steering cooler line that goes from the cooler to the reservoir. The cooler line is 5/8” inside diameter, the return line for the booster is 3/8” ID. I pieced these parts together at NAPA in a pinch, cost me over $30 for the Parts. You might find a pre-made T cheaper somewhere else. It’s a low pressure line so barbed ends and hose clamps work fine.
The top line coming off the booster goes to the power steering pump. To retain the power steering pressure sensor, you have to splice into the factory hard line. I cut the factory line about 1” above the sensor and installed a 3/8” flared union. It’s is NOT a compression fitting, it’s actually flared. This is a high pressure line
I cut the booster line to fit, flared that line and screwed it together
The bottom line off the booster goes to the power steering rack. It screws into the lower hole in the power steering rack. The Cummings line fit right in for me, that was pretty simple.
It was recommended to me to use ATF 4 transmission fluid in the power steering rack after this changeover. I’m not really sure why, I think it has to do with how it holds up in the winter and cold temperatures. I actually would love some more info on that, but that’s what I used. And just standard brake fluid in the lines. You will have to bleed the brakes after this.
I’ve only driven a few times since the switch, but the brakes are WAY more solid then the air system. You barely push the peddle to brake now. It feels rock solid. I haven’t had the chance to really test them out. Now in case you are wondering, if for whatever reason your truck stalls, you will STILL HAVE BRAKES!! I think there is a check valve in the system that keeps some pressure for a few brake applications. When I was tuning my new cam, I had the truck stall will driving a few times, so I can personally attest to them still working when the truck is dead.
I’m am really pleased with the outcome. On top of solid brakes, there is so much more room in the engine bay. It’s very easy to reach the back valve covers and spark plugs now, it was worth it just for that. It only cost me about $200 all said and done
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