I have an 05 ram 3.7 with about 107,xxx. For one thing I had a very very slight misfire every so often when accelerating quickly. It was very brief and inconsistent but happened every once and awhile when merging onto the freeway. Now on my way home yesterday out of no where, it dropped a cylinder I suppose and just started shaking and jerking terribly. No power and it sounded really bad, but I managed to baby it home. Any ideas?

 

3.7 & 4.7 known for it ESPECIALLY after an overheat.


I had to rebuild the 4.7 HO in a Grand Cherokee I owned from 2006 until 2012 after the radiator split. Nursed it home, never got over 235* and it was still hot enough for the aluminum heads to expand slightly.
It didn't drop the valve seat right away, but 2500 miles later one dropped, grenading that cylinder and taking the heads out with it.


A good read:


https://dodgeforum.com/forum/jeeps/3...p-carnage.html

 

1st thing on the to do list.. Check your plugs before doing anything.
You can buy both a leakdown tester AND a compression tester at Harbor freight for $40.
One will tell you if your valves are damaged and the other for compression. You could test bad on both and it could be one or the other, but atleast you will know if it's major or not.
Could be something as simple as a valve spring was weak and then just broke.

If those tests come back good, pugs/wires/coil pack.

 

Thanks for the feedback, It did turn out to be a simple fix. I got the code on cylinder 5 and swapped in a new coil and it runs like a top again. I had a friend who had similar symptoms and wound up with a fat bill at the dodge house so I panicked a little! Thanks again yall!

 

Good thing it was a simple fix - had it been a dropped cylinder it sure wouldn't have been. I had about 28 hours in my rebuild...