Yeah those gallery plugs can really leak when they do. Glad you found it.

 

in a weird way that's good to hear haha because I'm hoping that's my big leak. Relativity easy fix

 

There is a difference between the '94.5-'95 and the '96+ pumps. The early model pumps had a check valve in the pump to prevent the hpop reservoir from draining back oil into the crankcase when the truck sits. On the late model engines, that check valve is moved into the front cover. So if you used an actual '95 model pump, you now have a check valve in both locations. I'm not sure how that plays out. I know that using a late model pump on an early model engine results in drain down issues and a no start when the truck sits for a little while because there is no check valve at all in that configuration. There were 3 different hpops used on the OBS trucks..

-On 1994 1/2 and 1995 model year engines up to serial number 187099, the initial high pressure pump did have a drain check valve but did not have an edge filter. The edge filter was part of the injection pressure regulator.

-On 1995 model year engines starting with serial number 187100, up to serial number 201680, the high pressure pump did have a drain check valve and an integral edge filter. The edge filter was deleted from the injection pressure regulator.

-On 1996 model year engines starting with serial number 201681, the high pressure pump does not have a drain check valve but continues to have an integral edge filter.

 

I made a trip back to the junkyard and discovered that the truck I took that pump off of was in fact a 96. I took the ipr off and everything looked the same as what was on my pump.

 

Got my new plug in today and got her repaved. Good news, that was defiantly my problem. Ran the truck all night And hauled my cousin's car and every time I stopped I checked under the truck and no more leak! I urge anyone with a leak running down the passenger side of the engine superficially to check that plug. They can really leak some oil
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Glad you got it fixed! I had one leaking once and I left a trail where ever I went, lol.

 

Oh yeah, once the truck was warmed up if I parked anywhere for any more than a couple seconds there would be a puddle forming. I also run full synthetic which probably makes it a little worse

 

Haywire,

How much of a pain was it to change? I think I have to change them on my truck.

Red

 

Not bad at all. I simply took the v-babe clamp off the back of the turbo that holds the firm pipe on so I could move it out of the way a little bit. Then you should be able to fit a flex head 1/2 inch rachet (preferably a longer one) back there on the plug no problem. Take that one off, try to clean it up best you can and then reinstall your new one with some loctite #277. Took me about an hour and that's only because I dropped the nut to my band clamp be careful not to do that haha. And be prepared for some oil because I had about half a quart come out of there. And also you will have to crank the truck quite a bit afterwords to get oil all back up in the head. Sounds like a lot but it doesn't take long. Hope this helps!