What is an ok oil to run in my truck?

[greenpigs]

  Well I checked and the owners manual says to run 5w-20 in my 05 HEMI. I bought some full synthetic 5w-30 as it was on sale and plan on using that in it. The weight is more critical but I forget what the other number means and before swapping out the oil wondered what you guys thought.

THANKS in advance.

[Plumcrazy]

As a rule it's always best to run what the manufacturer recommends.  Because it's a truck I wouldn't worry about using 5w-30 this time.

The Hemi's in the cars have the multiple displacement system (MDS).   Using a heavier oil in them can turn on the check engine light.

[dodge freak]

Well I always was told that 10w-30 is the best and the only resone the factory says to use 5w-20 or 5w-30 is because the cars get better gas milage with the thiner old. One car -not much, but over the tens of thousands of cars they make it adds up . Back in 2000 we got a brand new century-no body laugh at me now-and the engine cap said use 5w-30, but I have used 10w-30 from the first oil change-which I did at 100 miles, and then about every 5000 miles. Still have the car and it has 175,000 miles on it. Burns a quart of oil every 2,000 miles or so. If that was my car I would use 10w-30. Oh  I live in Michigan by Detroit, if it was somewhere  up north or more to the west were during the winter it got -20 below zero alot of time at night then I would use 5w-20 but just in the winter. 5w flows better cold then 10w not much but a little, 20 is thiner hot then 30 but both are good unless you live in AZ were it gets 110 everyday in the summer. In my mopar I use 20w-50 all of the time but store it in the winter. If you really want to look up stuff check out google, I bet there is a ton of stuff on motor oil.

[dodge freak]

Oh yeah my check engine light started coming on and off at around 110,000 miles and stayed on all of the time at around 130,000miles. Engine was and still is running fine so I just put a piece of black tape over it. Why its on I don't care, car runs just fine-for a Buick. I have change the spark plugs around every 50,000 miles and wires too. Factory says 100,000 mile which I think is too much