Me, sortof...

Personally I use 0W40 for winter or 5W50 for summer. Here, in the US it seems the only available oil is Mobil 1 for those grades. So, why those?

Well, the lower number tells you basically how cold the oil can handle and the higher number how hot. A 5W oil is perfectly good for you car, if you don't do cold starts (without an engine block heater) in a very cold weather climates. Actually 5W oils should be good for -40F, but personally I like to be on the safe side and use 0W oils if 0F waether is expected in the area that I live.

So, why not 5W20, but 5W50? Well again this will depend on where you live and how you drive. As basically the higher the high end, the higher temperature the oil can handle. So, again I play it safe by using a quality full synthetic oil even for a road car.

Why waste the money?

For myself, I've seen too many engines that have been using these 5W20 oils. All olis changes done regularly and oils have been "good" semi-synthetic, part synthetic part mineral blend (usually called just synthetic to confuse the customer). Not 6 months ago I collected a quart of "tar" from a V8 with only 100,000 miles and regular oil changes. All this done according to manufacturer specifications. The reason for this collection of gunk? - A stuck lifter, caused by the same tar from these "good" oils.

What my ranting is about?

Don't settle for a "good" (semi) synthetic 5W20 oil, if you plan to keep the car for long. Spend that extra buck per quart of oil and buy true full synthetic oil. - Save the money now by not buying the six pack or by walking to the corner store next time. - You'll save money in the long run if you plan to drive the car long.

 

Using the 40w or particually the 50w is going to LOWER YOUR FUEL ECOMONY ( MPG ) and significantly. Probably 2 MPG or 4 MPG lower than you could get with lower vis. oil.

5w20 is VERY COMMON weight of Mobil 1.
I've found it in every store I've looked at in over a dozen mid west and western states.

0w20 is a little harder to find. Basically, I find the 0W20 anywhere along Interstate 80 and north. But there are some cars that Spec 0W20 for all year, all seaons, all temperature zones, so you can get it by special order in all 50 states.

HTH,
-John

 

I've been using Mobil 1 - 5W-30 since i bought mine in 06. I also just for good measure put some Lucas oil stabilizer in mine as well with every oil change, is it needed no, does it help i'd like to think so. After close to 100K on my FEH and 0 problems besides preventative maintenance i can't complain. Just remember that once you switch to a full synthetic oil you shouldn't switch back to conventional oil.

 

Actually the myth about not allowed to switch back to semi-synthetic (or mineral) after using full-synthetic is just that, a myth. There is absolutely no evidence to support that myth.

The myth may be based on some weird oils sold decades ago in the US that had compatibility issues with other oils. But this was well before synthetic oils. And when synthetic oils came out (readily available to motoring public) there was natural resistance against new and faint memory of this old problem. Thus myth was born.

You can mix and match modern oils without a problem. Synthetic and mineral alike.

Personally I like to buy quality oil that does not need additives to "boost" it's performance. In my experience mineral oils brake down easier and on the long run the engine will collect deposits of "tar". No "boosting" additive will prevent this. But again, I am talking about long term effects. - And as for the stuck lifter, FEH/MMH do not have these sensitive hydraulic lifters. But they can and will collect residue as well, but the problems shouldn't mount in as short period as with older style engines.

But I am not totally against these "snake oils" either. I have used with great success some products to wash out some of this tar from an old engine. And the amount of gunk coming out was just astonishing! But after this I did immediately change the oil and do yet another oil change in 500 miles.

And one thing more. ALWAYS change the filter when changing oil. This is yet another cheap insurance against possible problems.

About the W40 or W50 helping on fuel economy, I have not seen conclusive proof about that. But I do not say it wouldn't be possible. There is theory to support it, just haven't seen any real world evidence (yet) to support it.

And about 0Wnn vs. 5Wnn oils. There is no need for the 0Wnn oil, unless you expect extreme cold weather starts. Like I wrote, my PERSONAL limit is temps under 0F, but the oil manufacturers talk about -40F...

 

When I called the Ford Customer Service "hotline" years ago, they told me 5w20 was OK for all seasons, but 0w20 was recommended for owners who "frequently" have cold starts below zero 'F.

It is up to you what "frequently" means.

I have 4 months of starts below 32, and about 4 weeks a year below zero.
-John

 

Funny, Ford actually has same rule as me about 0W for below 0F starts. =)

Well, actually it's not really that surprising, as my rule is based on loads of discussions with different people over the years. It's just a nice rule-of-thumb the 0F. And as for "regular", I would say weekly when living in the area. And personally I would change the oil if I would be heading for a holiday where I would be expecting a start in a temp below -20F. And in your case John, I would use the 0W40 for winter.

Anyway the extra cost of using 0W40 oil instead of el-cheapo 5W20 is about $10. Personally, I just walk to the corner store a couple times more to save the money and keep my car (and myself by walking) in better shape.

As for W20. I totally agree with W20 being good enough for any regular use street car. The temperatures is street cars seldom gets that hot, specially in a hybrid where the engine is not stressed out. It's just the part that a good quality full-synthetic W20 doesn't exist. That's why I use the quality 0W40 and 5W50 in my cars.

 

Your Ford engine was designed to operate with an oil exibiting a cSt value of 8.4 approx. at operating temperatures (100 degrees C).

It is desirable to have a cSt value of 46 or so at 40 degrees C.

Oil thickens as it cools. If you are operating a vehicle in extreme cold environments, you want as low a cSt as you can get - 0w20 fits the bill here.

Years ago we changed our oil between the summer months and the winter months because we didn't control the engine temperatures like we do today. Your engine is designed to operate at 100 degrees C all year round and the oils specified contribute to engine cooling as well as lubricating moving parts. Do not use anything but 5w20 or 0w20 unless you are constantly towing/racing/operating your engine in the 300 degree F range.

Most engine wear occurs at start-up.

Oil pressure does not = lubrication. Flow = lubrication.

Look at the specifications for the oil you plan on using and don't go above 9 cSt at 100 degrees C or above 50 cSt at 40 degrees C. If you do, you are affecting engine lubrication and cooling and encouraging more engine wear.

 

I see O'Reilly Auto Parts has 5 qts. of Mobil 1 and Mobil 1 oil filter for $29.99 starting June 30th (limit 2 deals per customer).

 

My usual luck, no 0w20 at my closest store.

Even tho online, this store was supposed to have it, I knew I should have called first. Guess I'll call the others before venturing out. They did have 5w30 and 0w40.

 

I use Mobil1 0W20 oil that I usually purchase at the local Walmart for $6.25 quart.