Was just reading up on the sludge issue which affects the Dodge 4.7L and aside from poor oil maintenance habits, the thermostat was a main culprit in causing sludge issues. It seems that the oil does not get heated enough and this contributes to sludge. So, use a good synthetic oil and keep the normal thermostat.

 

That logic applies to all engines.. only way to overcome it is to change your oil like a crusty pair of undies and run some mystry oil through it right before you do everytime id assume.. i put a 180 stat back in but the damn thing is acting as if its 190 lol..

 

True, but some are more predisposed to sludge than others, based on design. You can get away with it on some.

 

I ran a 180 stat in mine, but I also was meticulous about oil changes and only used synthetic.

 

too high an oil temp causes it too (my oil with a 195* was over 220*) many vehicles have a 180* t-stat with no sludge (remember oil will get hotter than the coolant temp most of the time) it will still burn off the water and what not. Cheap oils, and long intervals does more than the temp in my opinion (after having to rebuild an engine because of sludge and speaking to engine builders about it)