Inline six with 241k, what would be the best motor oil to use?

 

In my 02 screw w/ the 5.4 I run Valvoline Maxx Life synthetic blend 5w-20 ever since my truck hit 75xxx miles. I have had my truck since it had 10xxx miles{got it for a song was a local lease turn in}. Before 75k I used Valvoline synthetic blend. I would stay away from Pennzoil{JUNK OIL FAIL For ex. my G-pa used it in his 76 Grand prix-when he went to have the heads done after blowing a head gasket there was WAX on top of the pistons}I would stay away from Quaker State also as they and Pennzoil are the same co. Kendall,Mobil-1,Havoline,Shell are all good oils. Good luck

 

Well i have a Inline 6 with the exact same mileage and i use the valvoline
10w30 conventional oil and after 3-4000 miles it still has a nice brown color to it. If you want the best synthtic oil look at Valvoline Synthetic or Mobil One Extended Performance. And X2 Stay away from pennsoil I dont think it would be a good idea to throw synthetic in a 240 thousand mile engine if it has never had it.

 

How about none of the above including a high mileage oil. Your 4.9 was designed with lots of ZDDP (zinc/phosphorus) in the formulation. None of the normal OTC oils are going to have much of it as it is suspected of killing the emissions systems should the ad pack gas off- like an engine that isn't driven much and accumulates moisture/condensation. So you'll need to get outside of the box a little for your oil. I'd suggest using Rotella 5w-40 synthetic. There's not really much in the way of it being a high tech synthetic as it's a mostly Gp III base oil. But it does have about 1200ppms of Zinc in the formulation whereas most of the oils today are below 800. It's also got a splash of moly in the mix for when things get really hot.

 

Ford recommends a 5W30 for that engine, so if you don't use that Rotella, I'd simply put any good brand of 5W30 conventional oil in it.

 

Thats weird my 94 e150 with the inline 6 says 10w30 on the oil cap

 

I use 10-30 Valvoline in my truck. I think it calls for 5-30 but I tried running it before and it ran out of the oil pan like water so I've ran 10-30 since then. The engine doesn't make any strange noises so I don't think it's really hurting anything.

 

They probably did the same thing they did with the newer engines - change the recommendation after manufacture. The late 90's that speced 5W30 now spec 5W20. I don't think 10W30 is gonna hurt an inline 6 unless you live in a really cold climate.

 

Thanks for clearing that up, Is 10-30 fine for high temps like 95-105 degrees?

 

I just looked at my owners manual and it says to use 10-30 in the 4.9 and 5.0.

 

The climate around here is crazy, I'll be running the truck in 90 degree weather the rest of summer but once winter rolls around it will be in the steady 20's or lower.
What should I use now, What should I use in the winter?

 

Well, for good cold weather starting, I'd use a 5w something.

 

SO I shoulda use 10w-30 for the rest of summer and then when winter rolls around go to a 5w-30?

 

Labnerd, I looked into this rotella stuff, All I have found is oil for big rigs and heavy duty diesels. Please explain what I should be looking for and where.

 

That's exactly what Rotella is - diesel oil.