@mace, I have performed the power steering pump and vacuum pump conversion that you brought to this site.  I hope you are still perusing the site and will see this.

 

The time and effort spent on this project (and the APPS relocate) has been very worthwhile.  Much engine space has been freed up and the power steering reservoir is right where it should be for easy fluid check / fill.  The reservoir is like the brake master cylinder reservoir – you can see the fluid level through the reservoir.

 

An unexpected benefit is that this direct mount power steering pump outperforms any previous power steering pump that has been on this truck.  There is no more stopping of the steering wheel when the power steering is under high demand, such as when maneuvering in tight spaces, steering from stop to stop with little forward or backward movement of the truck.

 

I started the project by finding a location for the new power steering reservoir, which was going to be right where the APPS assembly used to be.  Then I built a mounting bracket for the reservoir (shown below).  The first part of the bracket assembly is designed to let the weight of the oil and reservoir rest in the V slot.

 

 

 

 

In the above photo, note the welded nut where the tab on the top of the reservoir is screwed into the bracket. 

In the photos below, more brackets are added to fasten the unit to the engine. 

 

 

 

Below is the new location for the reservoir in the engine compartment - lots of space available for mounting with the removal of the APPS and APPS mounting assembly.

 

 

           

I don't have any photos of the actual pump mount, but the mounting is straight forward, especially with the addition of studs instead of bolts.  Much easier installation the old vacuum pump / power steering pump combination was.  I didn't use a gasket - just the grey Permatex RTV gasket maker.  The one thing that Mace did that I should have done (which he clearly mentioned) is to have the pump suction fitting turned down on a lathe from 22 mm to 19 mm to match the 19 mm connection on the reservoir.  Because I didn't do that, I have not-so-neat connections from the pump suction to the reservoir (another reason to not take a photo down there). 

 

@Mace, thank you again for making this possible.

 

That’s all, folks!

John

 

 

 

 

 

Edited January 17, 20251 yr by Tractorman

I’m glad it worked out. What a difference

 

Ive had to replace my electric pump recently already as mine died. I replaced it with a Dorman one. See how long that lasts…

Edited January 20, 20251 yr by Mace

I purchased the Standard Motor Products vacuum pump - not sure about the quality.  While performing these modifications, I also replaced my original vacuum operated exhaust brake (PacBrake)  with an in-line PacBrake PRXB for better performance at low engine rpm.  It uses an air cylinder, so the only vacuum load I have now is HVAC and the CAD unit on the front axle.

 

The old vacuum operated exhaust brake served me well - 70,000 miles on my old '99 truck and an additional 393,000 miles on my current '02 truck.  It will begin a new life on a site member's 2002 truck next summer. 

 

Is the Dorman vacuum pump any quieter?  What brand was you original vacuum pump.

 

-  John

I used the SMP from Rockauto originally. It was slow or so I thought. My vacuum switch recently died at the same time so I replaced them both and my EB is quicker now. 1-2 second delay turning it on and maybe 2 delay switching it off.

 

Noise is the same I find.

Im gonna need to do some more digging on this apps "delete" and this conversion. Very interested, possibly needs to be a article 😉

Here are some threads to peruse that may offer some insight. I have performed both mods about 1 year ago - well worth my time and expense.

• John

On 2/24/2026 at 4:38 PM, Tractorman said:

Here are some threads to peruse that may offer some insight. I have performed both mods about 1 year ago - well worth my time and expense.

• John

Thank you! Ill prolly dive into this with my new build. 24v Ram 1500 Cummins 😉

@Tractorman

Just cruising around doing some little research here and was wandering what vacuum pumps would be acceptable to use? There's honestly quite large variety online and some very expensive versions. I didn't see any specific VC pump listed. I haven't started my 24v 1500 build yet but I think I need to get a handle on this.

Were (2nd gen) only using it for HVAC and cruise so its not a "vital" part, meaning you prolly dont need the most "expensive-best" option.

The vacuum portion seems straight forward, get pump and supply key-on power and hook up the main vacuum line.

What all did you have/need to buy for your PS pump conversion?

Been a long while since I got to use this gif...... so

11 hours ago, Stanley said:

I didn't see any specific VC pump listed.

I used a Standard Motor Products VCP112 electric vacuum pump for my application. It was less than $100 from Parts Geek. This vacuum pump regulates pressure from 13" HG to 15" HG and there is no flow rating listed. It is suitable for my application because it only supplies vacuum to the HVAC and the 4WD CAD unit. My cruise control is operated by the ECM, so no vacuum servo is used. If you are going to use a vacuum servo, then air flow volume could be a concern for you.

My previous exhaust brake was vacuum controlled. The reduced volume of the SMP VCP112 made the exhaust brake slow to actuate and to release, which was not acceptable for me. That didn't matter at the time because I replaced the vacuum operated Jacobs exhaust brake with a PacBrake PRXB and air compressor at the time of the vacuum pump / power steering pump conversion. @Mace, who provided the information for this conversion, uses a similar vacuum pump as mine. He noted the delay of his exhaust brake operation as well, but it was acceptable for him.

Parts needed for Vacuum Pump Conversion and Power Steering Pump Conversion by @Mace .

Vacuum Pump Conversion

CON166 - pump connector (Rockauto)

VCP112 - vacuum pump (Rockauto)

Vacuum hose

Mini fuse tap connector

4 pin relay & base connector 

Power Steering Pump Conversion

4002056 plug - Cummins

RES0161 reservoir - Rockauto 

4988390 pump kit - Cummins performance.com

M20x1.5 to 6 jic fitting

The description for these mods is in the following thread.

• John

Thank you @Tractorman exactly what I needed. The PS mod seems a bit daunting but once I get all the parts and get to stare at it face to face I should have it licked. I might try to a article style build on it if I can remember, usually get to excited on projects and get them done and realize I didn't take any progress pics.

I did find that PS pump, just googled it and ebay has them for $160, some others double that. The VC pump I can get through oriellys for $123 then add military discount 😉

Too bad that guy isn't a member here anymore. Seems like he had some good ideas and knowledge to add.

That reservoir will do fine, I have just been looking to see if there is another tank that has some better mounting options. So far most of them only come in a 2 port design. A tee fitting might work since the 2 small ones are only returns.

1 hour ago, Stanley said:

Thank you @Tractorman exactly what I needed. The PS mod seems a bit daunting but once I get all the parts and get to stare at it face to face I should have it licked. I might try to a article style build on it if I can remember, usually get to excited on projects and get them done and realize I didn't take any progress pics.

I did find that PS pump, just googled it and ebay has them for $160, some others double that. The VC pump I can get through oriellys for $123 then add military discount 😉

Too bad that guy isn't a member here anymore. Seems like he had some good ideas and knowledge to add.

That reservoir will do fine, I have just been looking to see if there is another tank that has some better mounting options. So far most of them only come in a 2 port design. A tee fitting might work since the 2 small ones are only returns.

Oh I’m around ;)

I stand corrected! I guess all I been seeing was you as an unpaid member and thought you'd vanished lol. Glad your here!

If you’d like to take your power steering a step further here’s an idea to bulletproof it more.

I finished today converting both my 6 bolt PSC steering box and both hydroboost fittings to 6 AN/JIC. Now if I have a hose failure a simple 6 JIC hose is all that needs replacing vs the oem hoses that seem cheap and poorly crimped.

Edited 14 hours ago14 hr by Mace

Nice, I have access to pretty much make any hose a want with any fitting so I think ill be doing something just as you did!