I know there's been a thread on this in the past but I searched and couldn't find it. I'm getting ready to make my decision on this and I'd be interested in any comments.

First let me state I've already spent enough time at bobistheoilguy.com to reach geek status. So I'm not lazy, and I'm not firing off a new topic on this board because I won't spend the time to do some research.

I've got a 2003 Screw with 2,800 miles on it. Replaced the factory fill at 800 miles and will run the second fill, Castrol 5W20, until 3,800 miles. At that time I will either:

- Continue with Castrol 5W20 (I can "live" with this oil for a 20wt, it had a good used oil analysis report on bobistheoilguy.com. Has lots of moly in it. Not sure I trust a 20wt for the recommended 5k drain interval, though.

- Switch to Mobil 1 5W30. The MSDS shows a viscosity on the lower end of the 30wt range, barely above a 20wt. I'll run it for 5k.

I *might* change to Mobil 1 0W20 after it hits the market and I see a used oil analysis.

I realize there could be some voiding of...or "gray area" with...the Ford warranty if I go with Mobil 1 5W30. But a compelling post that stated "I don't care about the warranty, I would rather protect my engine the best I can because I expect to keep it long after the warranty expires" makes me lean toward the Mobil 1.

So...any thoughts? I bet there are some out there.

 

Just curious, when did they change to 5W20? I have a 97 F150 4.6, my wife has a 99 Windstar 3.8, my brother in law has a 2000 F250, 5.4. All say on the oil cap, 5W30 I suppose I would use what the manufacturer stated, they know a lot more about it than I. 5W20 seems awfully thin though, doesn't it?

R.K.

 

The manufacturers went to the 5/20 to save fuel. The thinner viscosity has less drag on the engine.

How many engines have you seen failed, because a person did not use synthetic oil?

 

I use 5W-30, either Royal Purple or Mobil 1 with Motorcraft filters. My next oil change will be with 0W-30 Mobil 1 on my wife's 2002 4.6. I just bought a 2003 5.4 so I will change at 3k at the dealer next time because I have a free oil change coming. After that either 5w-30 or 0w-30.

 

 

5w20 use started with the 2001 model year, although it somewhat depended on when the particular batch of oil caps ran out .

There are no documented internal changes to the motors between years that used 5w30 and 5w20. Ford released a TSB that also states that many years prior can also use the 5w20 oil.

Ford specd the 5w20 for CAFE reasons (fleet fuel mileage).

Both Ford and Honda use this as factory fill now. They also have specifications that exceed the standard API testing requirements in a few areas. The net result is that nearly all the 5w20 oils coming out are very high quality dino oils so they meet Ford and Honda specifications. Oil analysis results are also looking pretty good using the 5w20 oils with little difference from those using 5w30 oils.

Mobil 1 will be debuting a 0w20 synthetic oil in March, so you will still be able to use a xw20 oil and Mobil 1, although using Mobil 1 5w30 is also a good choice.

 

Hi~

I run 10w-30, now. I've been running Redline 5w-30 for the past 10,000 mi., but I have now switched to a 10 winter weight oil because I live in a mild climate year around. Plus the oil starts out as a 10 weight rather than a 5 weight. I'm using the 10w-30 Mobile 1.

Oil Viscocity WILL NOT adversly affect your warrenty, especially if you use a 5 or 10 weight oil. I even know of a 97 F-150 owner that put 15w-50 in his engine. Aside from decreased gas milage, the performance was the same and he now has over 100,000 mi on his truck.

My advice (just my opinion):

If you decide on dino oil, go with Chevron Supreme for they use a pure base stock. Change the oil no longer than 3,000 mi. intervals.


PS I also use a FL-820S Motorcraft Filter....you can't beat it!

If you decide on synthetic, go with Moblie 1, Redline (if you can afford it ), Royal purpal, Amsoil or some other good quality oil. You can change it every 5,000 mi. Much beyond 5,000 mi. there is some controversy, check the search button.


As far as viscocity, I'd personally stick with 5w-30 oil. The engine originally started off in 97 with that requirment, and there have been no internal structural changes, to my knowledge. I agree with the rumor that they just decreased the weight for better sticker milage and enviornmental issues.

Good luck

 

I agree with mf150.

I had a '99 V6 that I ran with Mobil 1 10w30 till 60K. Since I got my '01 5.4 4x4, that is still all I run. I change every 2750-3000 miles and I have not had any trouble at all with either truck. I am skeptical of the claim that you can wait 5000 miles. When I change the oil, the color is not that bad and probably could go another 2K. However, I don't think it would be heathy in the long run and its better to be safe than sorry. I noticed, cheeks, that you are in Texas too. With the weather we have, you can run either a 5w or a 10w all year round and you'll be fine. I tried a 5w on a few consecutive changes on my 99. FYI: My gas milage was about the same and no real difference running. When it came to my 01, I just kept running 10w30 and left it at that. My thoughts, since you asked, are put a good synthetic in, be religous about the changes, use good gas, and keep the air coming in clean. If you follow that, you shoud have no problem. I have lived by that since I started driving and I have never had engine trouble.

 

you know, when i bought my truck, it came w/ a years of free oil and filter changes @ the dealership. come to think of it, i havent asked what oil and weight they use! I regret to say this, and actually am a bit shocked, but i dont know what oil im running in my truck right now! yikes. its ready for its fourth oil change now, im taking it in on monday. ill find out then...for the love of god ill find out then


-Alan

 

Valvoline Durablend 5W-30 Semi- Synthetic, and Motorcraft oil filters for me.

 

I'm going by the book, plus I have the extended guarantee. If something happens, I don't want any hassles. My 2001 5.4 has only had Motorcraft 5W20 if the dealer changed it or Valvoline 5W20 if I change it. 38K miles, and so far the engine's perfect.

 

I broke my 97 4.6 in with 5-30 motorcraft for 6,000mi with 1 change at 3,000. Then i went to 5-50 castrol syntec and Prolong, I now have 109,000mi without any problems and no oil useage between 4,000mi changes.And i live in PA. where the wheather has been very cold and have no unusual sounds at startup.

 

Mobil 1 5w-30 full synthetic since 10,000 miles. Befroe that was non-synthetic 5w-30

 

Thanks for the replies, folks!

FYI, here is the Castrol 5W20 used oil analysis, it's an interesting read: http://theoildrop.server101.com/ubb/...=000213#000000

Bear in mind the Castrol in this instance was used in a different application....a Honda...., but it still has some relevance. Looks like a good oil, but I'd still change it every 3,000 miles and not the Ford recommended 5K drain interval.

 

Mobil 1 5w-30 here.