my new Ford says it requires 5W20. 5W20 is hard to find where i live. Is it a problem to use synthetic 5W30 instead of 5W20? Why are these vehicles moving towards this standard? The viscosity is better with 30 weight which would exceed the requirement. How could this be harmful?

Ford has tried to tell me that it could void their warranty by not following their guidelines.

Welcome.

Go to google. Type:

site:bobistheoilguy.com 5w-20.

Half the results will be this exact question.

Isn't there a Wal Mart near you?

I find it most comical that the most sensible weight for use in their extreme winter climate ..is also the most limited in availability. I would think Canada would be so far ahead of the curve on this.

It's obvious that they don't produce "in spec" fluids domestically. That means that it's the "regulated border" thingie like with filters.

Welcome to the forum!


Ford has spec'd 5W20 oils for a while now (2001+/-). There is MUCH more to an oil's performance than viscosity alone. 5W20 oils have to meet some very tuff standards. I highly recommend you do some diggin here on BITOG to help get you up to speed on the use of 5W20 oils. The factory engineers perform a lot of testing on their vehicles. They may not be the solution for all engines/applications, but where a vehicle can keep consistant oil temperatures in various climates, they work very well and offer an economy benefit.

I have a 5000 mile trip out to Utah pulling 6000 lbs of Jeep and trailer next month. I'll be running 5W20 oil. She'll be perfectly fine!

If you use your vehicle as the factory intended and don't modify or race it, you'll be fine with 5w20.

It is not right that 5W20 of many brands can be found at most auto parts stores in So Cal, and we never have anything below freezing (0 degree C) for almost ever, and it is hard to find it in Canada where it is needed 6 mos of a year.

Correction. The viscosity is higher, not better.

In the US this is very much correct: To maintain your warranty coverage you need to use service fluids that meet the specification set forth by the manufacturer of the vehicle. So in this case I believe that Ford could void your warranty for not using the correct type of fluid (5w-20). However, they cannot void your warranty based on brand or who completes the service.

Now with this being said, I am going to use 5w-30 as my next crankcase fill in my '04 F-150 w/ 4.6 that specifically states 5w-20 in the manual. My point is that you will not cause any harm using the 5w-30, but be advised that Ford has every right to void your engine warranty if there should ever be an oil related failure...highly unlikely.

The warranty may be a problem, but Falcon from Kuawit told me the engines I have in my two Fords, both call for 5-20, call for 5-30 overthere. I run M1 5-30EP in both of them. Last year I did a UOA on the Focus,9500 miles, and it was very good.
Bottom line, aside from the warranty, no problem with the 5-30.

thanks very much to all that have replied.

I have been using 5W30 in my 2001 F150 since I got it and it also says it required 5W20. 5W20 shows up in stores here ocassionaly but doesn't last long and usually the only thing I can purchase is 5W30.

There seems to be a lot of demand for this type of oil however my Canadian Tire store rarely has it in stock.

That engine was previously spec'd for 5w30 anyways.

My '02 Expedition is spec'd for 5w20, I'm running 5w40 in it.

IT'S ALL ABOUT THE AMBIENT TEMPERATURE!

Yes, I was shouting, but not in anger, just to get attention. If any short term issues occur with 5w30 rather than 5w20, it will be with '04-up engines with Variable Valve Timing (VVT) and likely those would be in cooler climates. Overall, getting the skinny on issue of viscosity vs VVT operation is elusive. We get some anecdotal material from owners that say A-OK for a 30 grade and a few bragging about 40 grade, but these people don't necessarily know what's happening inside the engine. On the other hand, we have cautions from Ford, including some direct from engineers... but they are a bit short of specifics. It seems clear, even factoring VVT, you could most likely get away with a 5W30 in a hot climate. Might even be more desirable for a hard worker in a really hot climate, but in a cooler climate where the oil may seldom or never reach it's rated viscosity due to being below 210F... who knows. The VVT devices are controlled by the oil. It stands to reason that viscosity would effect them. How much has yet to be answered. Me, I'm being a little cautious. My truck is well outta warranty but I don't particular want to tear into it (well, I DO because I'm a gearhead and I love working on engines, I just don't want to have to pay for it).

That's right,Gary. Down here, we live free and run 5-20!

Good post Jim. I've done a little experimenting with my 08 4.6 3valve Mustang and frankly I don't think it much matters what you run. I've tried M1 0W40 and it was as smooth and quiet as it was on 5W20 M1. I then tried a run of M1 5W30 and same thing...no noticible changes. So I'm back to 5W20 since it's under warranty and just easier not to worry about it. The VVT must have a little cushion factor built in cause mine sure didn't mind thicker oil. The crazy thing is on my 60 mile a day highway commute the mileage never varied between the oil's! YMMV

Well, in Texas with 0W40, Its kinda not surprising. Does not apply to someone living in Canada.