LH6-DOD-54-GMC

I'm swapping in a 2005 5.3 DoD engine from an Envoy Denali into a 1954 GMC 1/2 ton pickup on an S10 frame. It turns out that the oil pan on the Denali is front sump and the '54 needs a rear sump. I found that the Silverado/Tahoe pans fit fine with no modifications. Unfortunately, according to the oil system schematics, there is some sort of extra DoD only extra oil pressure regulator on the Denali DoD pan. Sooo, the question is can I add this valve to the truck pan or do I need to buy another pan that has the DoD regulator in it? My first thought is the 2007 Tahoe/Silverado pan because it's available as a 5.3 with DoD (now called AFM). BUT, it's over $200!! I already spent $125 on the truck pan. Any ideas?

rsz288

I thought it was simply an oil filter bypass valve that was added. I will check the L76/GTO style pan I have in the basement.

LH6-DOD-54-GMC

I did a bit more research and it seems that the DOD has two bypass valves. One is for filtering and the second is for maintaining pressure for the lifter manifold valves. I took a guess and checked out the 2007+ Tahoe since it also has (AFM) and found the valve. Just what I needed too. On the new Tahoe the valve is a threaded part. All I have to do is machine a flat above the oil filter boss and drill/thread the hole. Screw in the new valve and I'm done. I found a $100 difference in the truck pans so I may still save money with my 05 pan, valve purchase and machining caompared to the 07+ pan.

rsz288

Easy fixed....that's ingenuity for ya! No interference likely with the windage tray in the location marked on your photo?

IMVHO - the DOD regulator is not needed unless you are in an area that is frozen in winter, does not have block heating, and sees oil pressures over 75 psi on start up. I dont doubt that GM may have run into high start up pressures, which managed to get past the DOD solenoids, and kill 4 cylinders, so they had to add a regulator. Maybe...

FYI - the filter bypass has been in most engines since day 1 to bypass the oil filter if it gets blocked up....exception seems to be the F Body pan. Cant find a filter bypass on the F Body pan.

LH6-DOD-54-GMC

Well after some more tinkering it seems as though RSZ288 has hit the nail on the head, almost. Unless I can tuck the valve right against the side of the block I'll have windage tray and possibly crank interference! *$&@*@*!! It looks as if I still drill the same spot but machine it from inside, through the center threaded fitting for the oil filter, I may be able to machine a flat and install the valve that originally came out of the DoD Envoy pan. I do worry about cold weather since it gets into the teens here in winter.

I did find that GMPartsDirect sells the '07 GM pan for $164.42 or $200.59 delivered. They don't combine shipping though. This sucks because I want more GM stuff but the shipping would come out to about $89 for everything. That's too much.

Geezer's Garage

Hey AD man,
I missed this thread but thanks for the email regarding the extra pressure regulator. I just posted a progress report

https://ls1tech.com/forums/conversions-swaps/946187-5-3-lh6-progress-problems.html

and I believe the lack of the regulator is causing some of my problems. Right now I'm thinking about plugging the DOD passages but I may also look at fitting the regulator into my GTO pan.
The Geezer

rsz288

Hey Geezer, just posted in your other thread re using the LS2 valley cover to block off the galleries to the DOD lifters. Also replace the DOD's with regular lifters if you can. Its safer, especially if you have a non stock cam.

rsz288

FYI > Posted this in the other thread too:

Though that there may be some interest in what is inside the DOD DEAC lifters, and potential extra points of failure:

Left hand side shows the main lifter body with the smaller lifter oiling port, and the larger DOD control port.

Above the lifter body is the DOD plunger return spring and retainer, and washer.

On the right hand side is the DOD plunger, showing the activation pistons and preload spring, and above that the pushrod seat, oil metering plate, lifter plunger with lifter check valve and pre load spring.

The activation pistons measure 0.275" in diameter, and require around 1 lb of force to compress to fully flush with the DOD plunger. (around 16 psi?)

When they are fully flush, they dis-engage the DOD DEAC plunger which carries the lifter plunger and pushrod seat, from the main lifter body, allowing the main lifter body to ride up and down on the cam, without transferring any motion to the pushrod.

Oil pressure is applied via the DOD DEAC solenoids in the valley cover, under ECM control, which depresses the activation pistons so they dis-engage from a slot in side the main lifter body.

When the ECM commands re-activation of the 4 DOD cylinders, the oil pressure is released which allows the activation pistons to extend under pressure of the their pre load spring and be pulled by the return spring back to their normal operating position and re-engage the main lifter body allowing the lifter to operate normally.



cheers!

LH6-DOD-54-GMC

I finally got fed up and swapped a 2007 turck pan onto the engine and raised the engine two inshes to clear everything. Now I'm sitting pretty and soon the engine will get started.