Electric Vacuum Pump Conversion:

I have deleted my OEM vacuum and power steering pump(s). Instead, I have modified it by replacing it with a midrange setup for steering assist; however, I still need vacuum in order to activate the HVAC controls and to activate my exhaust brake.

Although the OEM factory pump never gave me any issues and supplied all the vacuum I needed to work, such as the HVAC and the exhaust brake, the OEM Power Steering did.

I have replaced the OEM Power Steering Pump multiple times. In all cases, the pump would not maintain enough pressure and turning the wheels at a stop during idle was almost impossible. Compound that with the inevitable oil leak between both pumps, I figured there was a better system.

So, this is where the "midrange" setup comes into play. The 24V ISB was used in multiple applications (not just Dodge). Even though they were not used in another pickup, they were used in midrange sized trucks like Freightliner FL60 &FL80, Ford 650 & 750, Kenworth 370, motor homes, bread trucks, etc, etc. It was the engine of its era.

Trucks with vacuum controlled cruise should work also. This particular modification applies to my setup only; (the midrange setup for steering assist). My cruise is ECM controlled. I have the non CAD front axle, so my vacuum demand is limited. On SD applications, they use it to lock the front hubs and HVAC on their trucks. So I feel it should work on any of our vehicles.

I used the same pump from the SuperDuty and 3rd Gen RAMS (same pump). I picked it up from Rock Auto along with a Mating Connector. I drilled 3 holes and mounted it on the fuse box cover, in an easy to service spot. For plumbing, it goes to a control manifold for the EB, and tees off into the OEM vacuum line on the firewall. I do not use a reservoir like FORD uses, but you could run one if you desire it.

For power, it gets fused voltage from the PDC power stud, which is also the relay supply power (pin 30). The relay trigger is controlled by a fuse tap in one of the PDC fuses, that is hot only when the key is on, so it does not run all the time. The pump has an internal governor, so when it reaches its vacuum threshhold, it shuts off. If it is always running, you most likely have a leak that you need to repair first.

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How did you deal with the old vacuum and steering pumps?

1 hour ago, Sycostang67 said:

How did you deal with the old vacuum and steering pumps?

He removed both units and installed a gear driven power steering pump directly onto the accessory drive gearbox. He also installed a remote power steering pump reservoir.

Here is a link to his original post regarding the conversion. You will need to scroll through the whole post as he talks of other conversions, as well.

I made the same conversion myself - very happy with the results. It's nice having an accessible see-through reservoir. The direct mount power steering pump definitely out performs any of my previous pumps, including the OEM pump.

• John

Edited yesterday at 03:28 AM1 day by Tractorman