This morning I was driving home from work and randomly my truck just started to shake from the engine randomly starting to run super rough. It was running perfect and then while pulling up to the light it started running so rough I thought the motor might blow. I was able to limp it home. It lost so much power it wouldn't do much more then about 40 mph. It also did not throw a CEL. I can start the truck no problem it fires right up but instantly runs like it's goin to blow up. The whole truck shakes from the rough idle like as if it has a monster cam in it. Any help would be great, thanks .

 

What motor? How many miles?

 

It's the 5.7 with about 185,000.

 

http://m.youtube.com/watch?feature=youtube_gdata_player&v=kSgOzpfmdfQ

I took this video this morning to show what it is doing. It was running fine then out of no where it started running like this coming up to a read light.

 

Ok 02-04 early 5.7 Hemis were prone to valve spring failure.
Do a search on here for more info.
Typically they run rough as a dog, can't hold an idle and have poor power as you have.
Can't say I remember them throwing a code either when that happens.
Pulling your valve cover and closely inspecting the valve springs, might be the way to go here.
Al.

 

I'm pretty sure it is a valve spring. I started this morning by checking the fuel pressure which was good. Then I did a compression check a had 0 compression on cylinder 3. Tomorrow I will be pulling the cover to actually put eyes on the spring.

 

Well good luck and I hope it's an easy fix, in that the valve hasn't impacted the piston.
If you find that the spring has snapped, rent/loan a bore scope and look down into the cylinder checking the piston top and valve seat for damage.
The top piston landings are known to also chip/snap off or squash down stopping the top ring from turning.
If you spot any damage, time to pull the head and look deeper.
Post up how things go and as I say, good luck.
Al.