will royalpurple 5w-20 work fine too? you all say amsoil is good for the hemi..but what about the royal purple?

 

Thank you for all of the posts. Sorry it took so long to get back.

I am have decided 90% that I am going with Mobil One 5w20. It is the same price as Amsoil and is much more accessible than Amsoil - it seems kind of hard to find and buy on a regular basis. I just heard that royal purple is great stuff - I am going to look into that as well.

I am not going to use seafoam to clean it. I will just drain out the old oil and pour in some mobil and run it for 1000 miles and have it changed. That seems to make the most sense.

 

it is my understanding that once u use synthetic u have 2 keep using it or its useless i could be wrong, like star said what about royal purple. i usually save my oil when i do an oil change and put it in the wifes car lol

 

For 3.7L/4.7L engines SAE 5W-20 engine oil is recommended for all operating temperatures. For 5.7L engines SAE 5W-20 engine oil is recommended for all operating temperatures.These engine oils improve low temperature starting and vehicle fuel economy. Refer to your engine oil filler cap for the recommended engine oil viscosity for your vehicle. Vehicles with 5.7L engines equipped with Multiple Displacement System (MDS) must use SAE 5W-20 oil. Failure to do so may result in improper operation of the Multiple Displacement System (MDS).

What year is this info out of? 5W-20 for the 3.7/4.7?? I thought it was 5W-30?