I have a 1998 Ranger with the 2.5L engine... For awhile, I was putting in 10w30 and all was well.

I went to get some oil yesterday and Oreilly's books said to use 5w20 and their computers said to use 5w30. I found some Ford (motocraft) branded service documentation online that says to use 5w20. Just seems odd that there are the 2 different weights being "correct" for this engine.

I know it really isn't a huge deal but, with the truck having close to 120k on it, I want to do the little things that will make it last.

 

shouldnt matter, as long as you do regular oil changed the weight shouldnt matter that much

 

The weight matters in FORD engines for some reason.

I used the 10-30 and got lifter noise, went back to 5-20 and the noise went away.
I now use the 5-20 weight Synthetic Oil and no noise.

So go by the book all the time and all will be well, go to a higher viscosity and you will get noise from a Ford.

 

That is what was driving me nuts... I ran 10w30 and all was well with the engine... I decided to swap it over to a different weight. When I was looking for the "stock" oil spec, I was getting conflicting information on the usage of 5w20 and 5w30.

 

You'll gain some mpg with the 5w-20.

That's why they went to a thinner oil.

 

See, I could have SWORN that I read a document awhile back that Ford released talking about consumers switching their vehicle over to 5w20 or 5w30. Of course, I can't find that now that I want to use it as a reference.

 

Stick with the 5 W 30...almost every oil company makes it and its always on the shelf. I use 5 W 20 in my 07 2.3 and I make a mass e-mail to the family every time to stop in and get a case for me from whom ever has it on sale. It should be popular by now cause of the four cars I change oil on its printed on 3 of the oil caps. 5 W 20 in thinner at start up so it flows faster through the engine but that leads me to believe that it also drains away quicker so the engine might be drier at start up over night.

 

Exactly what happened to me when I purchased the 10-30 on accident. Staring at the 5-20 and went home with the 10-30. Lifter noise within a few hundred miles. Switched it back noise went away overnight.