Im getting ready to change my oil it has 78,000 miles on it should i stick to 5-30 or go to a different weight if so which one i should i go to and will it make any difference?



Thanks

 

If you arent having any issues I would stick with 5-30, as it is the perfered oil for this engine and obtains a very slight increase in MPGs.

 

Like Eric said, there's nothing wrong with 5W30 (even though the main reason it's recommended is to help GM with the CAFE averages). Down here in Texas I use 10W30, but that's a personal preference.

 

Valvoline Durablend 5W-30 every 5000 miles....136K and still running great. Never need to add between changes.

 

Question...will the 'higher mileage engines' oils affect mpg minutely or at all? Are they just advertising and not necessary? I have 270000kms on mine.

thx

 

The primary advantage to HM oils is the additive package they contain for conditioning the seals in the engine that can harden with age. They will not do anything for gas mileage, but can be beneficial for the engine in correct circumstances.

And, BTW, Garry, glad to see that you don't buy into the archaic '3,000 mile oil change' idea. My research and analysis of oil from my engine shows that any good dino (non-synthetic) oil can go 3,500-5,000 miles inthe 4.3L engine without a problem.