Does any one know why ford switched to 5w30 from 10w30?

Would it be ok to use 10w30 instead of 5w30? I like to use Mobile1 and it is hard to find it in 5w30 around here. Yes they do cary it, just not as much as the 10w30.

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Never mind, i found my answer at

https://www.f150online.com/forums/sh...threadid=64077

 

It's fine to use 10W30 instead. The car companies only recommend the thin stuff for slightly better fuel economy.

 

I agree, I run 5/30 in the winter and 10/30 in the summer.
Terry

 

If you're running synthetic oil then 5w30 beats 10w30 all the time. It simply offers a wider temperature range of protection.
Synthetic will remain flowable at low temperatures and hold together better at high temperatures. There's no reason not to use it.

Look what Ford recommends. If you blow your motor and they determine you were using oil out of spec like 10w30 then you could be sh*t out of luck for warrantee.

 

Yea, you get a little better gas milage, but I was told Ford wants the 5W oil to get to the upper valve area a little sooner, can anyone say "PISTON SLAP?"

 

LMAO!!!!!

 

5W30 is for Ford's C.A.F.E. fuel economy standards. If your engine blows it will not be because of the difference between 5W30 and 10W30. Actually, piston slap will lesson a small amount with the 10W30. Ford has to prove that it caused it, and that is impossible. Metal fatigue or over-reving is what usually causes engine failure. Low oil level, etc.

 

I'm not worried about major engine failure from piston slap. I disagree, in that the thinner oil seems to quiet my engine quicker when it is really cold out.

 

Is it safe to run 10w-30 year round?

It never gets below 15-20 degrees. There is usually one or two weeks of below freezing temperature.

 

Do we all understand what a 30wt oil is?


They are the exact same viscosity at 100C (That is 212F for the rest of us).

The fact that 5 w30 will pump faster in cooler weather is a plus, since it has been determined that some wear is caused at start-up.

Here are the viscosities of 3 Xw30 oil. They are all Amsoil, 0w30, 5w30, 10w30

11.3cSt 0w30
11.7cSt 5w30
11.9cSt 10w30

A 30 weight is considered 9.30 to 12.5 cSt. So you can see that all of these oils are well within the 30 wieght grade.

 

I can give some advice from my experience. I started out using regular oil. As soon as cold temps became apparent I starte hearing tapping noises for a few seconds at start-up. Truck had around 8,000 miles on it. I switched to Synthetic and the problem has completely gone away. I could not believe it but it worked. Needless to say I am synthetic all the way now. By the way I started with 5W20 regular and went to 5W30 syn.

 

If you have temps consistently below 30 degrees, run 5w30. I figured this was common knowledge.

 

Common knowledge is to use what the Owner's Manual says.

 

My 99 Off Road had piston slap around 6600 mi. I switched from 10W 30 to 10W 40 and the problem was gone. Since then I have switched to 10W 30 Synthetic and my mileage has got slightly better.

With 10W 40 I ran it for 2 oil changes and it ran fine. It was summer and I changed to the synthetic before winter.

 

Peeps you must excuse Dennis. He's older than dirt and seems to troll around and reply after almost every post I make, good or bad. He is an expert on ALL things because HE says he is.