Tractorman

There is a single connector with two black wires that are connected to the positive post of the driver side battery. These wires supply power to the intake manifold heaters (grid heaters). Within a few inches of the battery connection, you will see two fusible links - no fuses. Disconnect the the single wire connection. There are two fuse group locations. One is called the Power Distribution Panel (PDC), and the other is called the Junction Block. The PDC is located right beside the driver side battery. Th Junction Block is located on the left end of the dash. The driver's door must remain open for access. Hope this helps. John

Sounds like you are on the right track. The intake manifold heaters draw about 100 amps each - there are two of them. They are automatically in operation below 60°F ambient temperature. With the key on, engine off, the heaters are on while the "Wait to Start" lamp is lit. After the engine is started, the heaters post-cycle until a specific engine operating temperature is reached, or the vehicle speed reaches approximately 25 mph. The post-cycling current is higher than the alternator output, so it is normal to see the dash voltmeter drop significantly. This is why I recommend disconnecting the intake manifold heaters while diagnosing a low voltage electrical problem. John

I would be looking into this before doing any parts replacing. Was the intake manifold heater post-cycling when you were seeing the voltage drop on your test drive. If you are not certain, then I recommend to disconnect the intake manifold heater to simply troubleshooting the voltage drop. In normal operation, when the manifold heaters have finished their post-cycling, the voltage powering the VP44 should be steady around the 13.5 - 14.2 volt range. Steady is the key word. If the voltage continues to fluctuate wildly at the VP44, then you should check the power supply to the VP44, ECM and the PCM; but more importantly you should check that you have good operating ground circuits. John

I agree. John

@Mace , I think you saying that your are at 442,000 kilometers (275,000 miles) on your truck, currently? I know other people (not very many) that also have had the same long life on their injection pump. I'm at 402,000 miles on the truck with 315,000 miles (507,000 kilometers) on a replacement injection pump. The first pump was replaced under warranty at 87,000 miles. Also, a new in-tank lift pump was installed under the same warranty, even though the original lift pump was still in good working order. My replacement fuel injection pump operated with only 6 psi @ idle and 3 psi @ WOT from the in-tank pump for the first 150,000 miles. I replaced the in-tank lift pump with a used frame mounted FASS 65 gph lift pump - the in-tank pump was still fine, I just wanted the ability to do a road side repair if the lift pump failed. The used FASS pump is currently in use - 12 psi @ idle and 6 psi @ WOT. My replacement fuel injection pump has never received any two-stroke oil, nor any fuel additives, nor any other special attention. I have run the Smarty tuner on a mild tune for 150,000 miles, and RV275 hp injectors for 150,000 miles. John

Ok, What is the secret? John

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

That makes more sense. Since the sleeves have been loose for awhile, they probably have worn into the clamping "ears" of the mounting assembly. This will make it more difficult to achieve the right clamping force so that the steel sleeves don't move around after you install the new bolts. I recommend to closely monitor that clamping force for a few months after the truck is back on the road. John

I am not understanding cause and effect here. Since the lower shock bushings have an inner steel sleeve that gets clamped tightly by the compression of the mounting bolt, there would never be any wear on the bolt. The only way that I can think of in which a shock bushing would be destroyed after 5 minutes of operation, would be that the incorrect shock absorber is being used (resulting in the lower mount receiving the full weight of the vehicle during compression, or the full weight of the axle assembly during a rebound). If you are getting aftermarket bolts, be sure the bolts have a hardness of 10.9. John

Your truck: 2wd or 4wd? John

My vacuum pump (a Dorman) is protected by a 15 amp fuse. The vacuum pump probably draws around 8 amps. John

How are you checking voltage for the lift pump? Where are your test leads connected? Ignition key on - lift pump runs for 1/4 second Bump start, leave ignition key on - lift pump runs for approximately 20 seconds The ignition key must be turned off between bump start tests. John

You may want to consider @Mace 's vacuum pump removal / direct mount power steering pump / remote reservoir conversion. The vacuum pump would be replaced by a small electric vacuum pump. I did this conversion myself and I a very happy that I did it. The best part of this conversion was a far better performing power steering pump, a see-through remote power steering reservoir that is very accessible, and the elimination of the gear-driven vacuum pump / power steering pump combination. I went one step further and remounted the APPS throttle control from the engine onto the brake booster / master cylinder mounts. The first two photos are my truck and the third photo is Mace's truck. John

I have no personal experience, but I have heard that Torque King is a good source. John

If I am understanding correctly, the engine died because the lift pump was not operating. If this is true, then one of two things could be happening: The engine died because the VP44 internal vane pump could not pull fuel through a non operational lift pump. Some lift pumps are built this way, others have a directional free flow when non operational. The engine died because the VP44 internal vane pump was drawing air mixed with fuel from possible leaking fuel line / fuel line connections between the lift pump and the VP44 injection pump. I would be more suspect of #2 since you are seeing it take awhile to build lift pump pressure after the engine starts. I have actually installed a fuel line with a check valve that bypasses the lift pump just in case I have a lift pump failure. If a lift pump failure occurred on a road trip, the fuel supply would not be interrupted - the fuel would be drawn around the lift pump by the VP44's internal vane pump - no performance loss and no damage to the VP44. I could repair the truck when I get home. John