I have seen and heard lots of reviews on the 4.7s prematurely failing due to sludge build up, but my durango has a 4.7 and has been religiously maintained using high quality dino oil for almost 150k miles. Upon removal of the valve covers i noticed only a slight amount of varnish (normal for any car), but no sludge build up. So is the 4.7 really a known sludger? or are these horror stories coming from people who don't know how to maintain their vehicles?

 

Hi eric, I did a search for you and here's one of the many results. HTH.
https://dodgeforum.com/forum/1st-gen...25-sludge.html

 

Answers: No. Yes.

IndyD

 

nope, no sludging issues with the 4.7 if it is properly taken care of, DAMN TROLLS

 

There is no issues with any of Dodge's motors. The problem is their owners not changing or using sh!ty oil.