I have a 4.7 L 2000 Durango I've been trying to fix. It came to me running only on the passenger side because the cam drive pin on the drivers side was sheared. Removed heads, replaced gaskets and cam pin and timing chains/gears. Now that it's back together, the passenger side cam is 90 crank degrees advanced with all the timing marks spot on.
Here's a video showing the timing marks. Ignore the audio about not knowing the cause. The cause is the pass cam is advanced. But I dont understand how or why it is. This is the reason for this post and the answer I'm looking for. When I took it apart this last time it was attempting to run on the drivers side but has no compression on pass side.
https://www.youtube.com/watch?v=i9qIbM71BWw

Here's a picture of the marks I made before I ever took this engine apart and they are off as well

Is there any chance that the dowel pin sheared again? If you take the bolt off in the center of the cam pulley, is the dowel pin still straight-up in the slot behind that big washer?

If both cams have the dowel pin straight at the top (behind the washer), and the crankshaft is at TDC - and the timing chains are all on - it should be in time.

Any chance the dampners (almost hydraulic lifters?) aren't functioning - and not opening the valves?

You're right that's the only thing left to check, is that the pass side dowel pin is intact....and I will do that tomm....but it was fine when I put it together, and nothing has happened that might cause it to shear....The bolt was torqued to spec.

That's really the only way I can think of for it to be 90° out of time on one head.

I remember getting frustrated with all the dots and different colored links for alignment in the past. Then when I just put the cam dowels straight up on top with the slots straight up, and with the lower sprocket/balancer at TDC - it all went together without a hitch.

Yea I've had this apart twice and in theory it's simple, but for some reason this one aint right.....

I've figured out the problem. When the pass side gear went back on the cam rather than slide over the pin, it pushed it farther into the cam. And now the pin barely protrudes and the gear had moved. Now to figure out how to get the pin to move back out....May have to destroy it and install another.

Any chance you can drill a small hole in the dowel pin, thread in a small screw and see if you can pull it out?