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I couldn't agree more, good advice !!


PS: Below is a post by Chrysler Engineer 5 digits, RIP Ken.

Intermediate Shaft / Oil Pump Indexing

For those who have ever had intermediate shaft or oil pump gear devastation, there is a method to improve gear meshing and component longevity.

As much as we'd like to believe that these components are precision machined to strict standards, they unfortunately are mass produced components with a wide quality acceptance band.

This means that the journal, gear tip, and tooth cutting processes for both components in addition to oil pump gear centering on the shaft and the distributor hole machining in the block can all amount to a noticeable uneven mesh, between the components.

This can be observed during the engine assembly process as variation in the rotating effort required to turn the intermediate shaft sprocket upon installation in the block.

This is typically caused when 'minor' non-concentric high spots on the oil pump gear are aligned with high spots on the intermediate shaft.

Although, there are a few easy steps to reduce the chance of component failure and a catastrophic event should either gear shear and cause a total loss of oil pressure.

1. With the oil pump installed, Loc-tite on the oil pump attachment bolts, and the oil pump attachment bolts near snug; install the intermediate shaft

2. Rotate the oil pump housing in its mounted position to realize how much the oil pump housing can be turned to the left and right, while visually noting travel relative to the mounting bolts

3. With the level of travel determined, clock the oil pump as close to the center position that was determined by the previous step

4. Torque the oil pump attachment bolts, per the manufacturer's recommended specification

NOTE: The previous steps have minimized the chance that the oil pump is preloaded to one side of the engine block distributor/oil-pump hole because the oil pump mounting flange surface is not always 'true' to the oil pump center-line.

5. Install the intermediate shaft retaining cover without the anaerobic sealant and lightly tighten the bolts that hold the cover in place

6. With the intermediate shaft key in place, install intermediate shaft pulley

7. Rotate the shaft by turning the pulley while noting the consistency in rotating effort, throughout several rotations

If the rotating effort is not smooth and/or consistent throughout several rotations, proceed to step 8, otherwise proceed to step 9.

NOTE: If the following steps are repeated numerous times without improvement, thoroughly inspect each component for obvious signs of significant manufacturing defect and replace as needed.

8. Re-clocking the intermediate shaft

Remove the intermediate shaft pulley

Remove the intermediate shaft cover

Note or index the pulleys/shafts current position

Remove the intermediate shaft, re-clock the shaft to one/same direction, by 90 degrees

Reinstall the intermediate shaft

Return to Step 5

9. Remove the pulley, intermediate shaft retaining cover bolts, and cover

10. Complete the final installation of the intermediate shaft cover and pulley hardware per the manufacturer's recommended specifications

The above process can provide the best possible component mesh and gear loading by improving awareness to minor manufacturing variation, aligning those variations in a manner that minimizes excessive component loading, and minimize the resulting wear.

My advice is tear down your old pump and inspect. If it is in good shape, clean thoroughly and reuse it. They don't wear out like many other engines. Might not be a bad idea to buy a new pickup, they are sometimes difficult to clean and they are inexpensive.
I personally prefer the aluminum case OEM pumps to the Melling cast iron pumps. If you do happen to find some NOS Mopar pumps and buy one, tear that one down and inspect carefully. I've bought a half dozen or so over the years and they had rust, died up assembly oil, casting flash inside pump, and some didn't turn very smooth until they were gone through.
I would also port match the block to the oil pump. That is worth a few free horsepower. You will find quite a bad mismatch there.
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