Hello.
Does it really matter between 5w 20 and 10w 30?
I grabbed the wrong stuff off the shelf and have not changed it yet but does it matter? In another 3000 miles I'll put the 5w 20 back in. What's everybody think?
Thanks

 

forgot to mention, it's an 03 v-10, 60000 miles

 

Are all quarts 10w30?

 

It is rumored 5w-20 is recommended by Ford to improve gas mileage in a lot of their vehicles. I doubt 5w-30 would even matter. But anyhow, 10w-30, you should save it and use it during the summer months perhaps, if you insist on using it. Or take it back and trade it for 5w-20.

 

yes, I bought a couple of 5 qt containers

 

I would return it then and get 5w20

 

Seeing that you are in ohio and the temps are very cold I would return it and get the 5w20, if it were summer time or you lived in a warmer climate I may have a different opinion.

Rc

 

mixing it with right stuff would net you 7.5w25...better than 10w30 if you cant return it

 

i have a 2000 limited V10 and i have 5w30 in mine and actually my owners manual calls for 5w30...
i already had the oil so i used it, but i am in south FL and will go to 5w20 on the next change...
i read that ford changed the recomendation for better fuel consumtion, but only after they determined improvements in oil mfg have allowed them to do so... i don't remember when but there is a tsb on it that you can look up also...
i notice no loss in MPG by having the 5w30 in it...
i had a thread running but my concern was more about switching to synthetics in a higher milage engine (92,000+) than the weight...
i think you would be ok using it... it is the 5 that effects cold starting, and the 20/30 that is most important at operating temps... in my opinion the difference in the two is so small it won't hurt anything...
you can call ford and see what they say...

i have all reciepts for mine from when it was new, and it has had 5w30 in it for at least the frist three years... i am still going through all of that stuff...

 

It does not matter. The oil specs in other countries call for 10W-30 in the V10 ... mostly because 5W-20 ain't available in many places. I run 10W-30 in mine because 5W-20 ain't a whole lot better than sewing machine oil. Some may say the V10 is built to tighter tolerances. Hogwash! Most factory-built tolerances are pretty broad ... they're better than they were in the 60s, but there's still a good deal of tolerance in factory-new engines. To prove it, all one needs to do is look through a factory service manual to see the allowable limits with new parts (not the wear limits). If anyone cares to disagree, CFICARE. I'll be cancelling further updates from this thread anyway.

 

Wow...are you 4 yrs old?

I agree that is there is probably not much difference between 5/20 and 10/30 but it calls for 5/20 so use it. anything else is fine for shorter drain intervals.


I'm gonna go run and hide....

 

My experience has been that the Ford modular engines do prefer the lighter weight oil. On my Town Car, when I ran thicker oil the car would actually idle rougher. Thinner oil will start pumping pressure through the engine faster, as well, which is never a bad thing. Clearances are tighter than they used to be, so there's less of a "need" for thicker oil like there was 40 years ago.

I'd say it doesn't matter and you won't notice a difference. That said, one thing I have learned (as an engineer of an OEM engine manufacturer, and formerly a mechanic) is don't second guess the manufacturer as a rule. They've done more testing on these engines than all of us combined ever will. Chances are, if they give you a requirement there is some reason behind it. Doesn't mean it's always a good one, but if 5W-20 was actually going to negatively impact your reliability, it wouldn't be in there as recommended for use. Doesn't mean that the factory always makes decisions in your best interest, but at the very least they know more about your engine than you do. With certain exceptions, you're best off just leaving things factory if you want to get the best longevity out of your truck.

 

It could be an excuse not to warranty something. All they need is a reason.