2002 4.7 with 160k on the clock

Should I be running the 5w30 still or should I run something thicker? Cold weather is not a issue where I live.

Dino oil or synthetic?

Engine has no leaks, no smoke, runs good and all ...... Looks like the p/o did a good job of keeping up all the fluids on it too

 

It should specify in your owner's manual, I run 10w30 in my Dakota in the summer but 5w30 in the winter but mine is a 3.9

 

Manual says 5w30 ......... With our older GMC engines we tend to go up in weight over 100k miles, so just wanted to know what the 4.7 crew does