I just picked up an 04 4x4 5.4l and per the records, it is due for an oil change. The original owner used Royal Purple from day 1, and I was thinking of staying with it.

Any thoughts?

What viscosity should I use?

p.s. Anyone know how many quarts the 5.4 takes???

 

Ford recommends 5W20. You may run into problems further on down the road with the VCT system running oils thicker than what's recommended. Stick with Motorcraft filters. And about 6-1/2 quarts should fill 'er up.

 

I just tried royal purple, and noticed a slight increase in MPG, so I will be sticking with it.. It is expensive, but I think its worth it...

 

Yep ford says 5w20 so might as well just go with that. And with a filter change you are looking at 7 quarts i believe..

 

Damn, this is going to be one expensive oil change..

My wifes Mazda 6 has an internal oil filter like a motorcycle. I dont have the tools to get it apart, so it needs to go to the dealer every oil change, and that still costs about 55 bucks..... So I guess this aint bad...

 

I don't like my truck enough to warrant spending big bucks for good synthetic oil. Motorcraft bulk 5W20 for me.