Can I use 5W30 instead of 5W20?

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Originally Posted By: k1rod
I bought a 2012 Ford Fiesta for my daughter and I was surprised to see that the car calls for 5W20 motor oil. Unfortunately (or fortunately depending on how you look at it), I have several cases of QS 5W30. I guess what I don't know is if there is a real technical reason for using 5W20 or if it was just called out to meet some drubbed up CAFE standard? I know somebody's probably going to jump in here an stearnly warn me about invalidating my warranty but I really don't believe Ford would ever be able to tell the difference. Heck, my oil analysis company can't definitively tell the difference. And conventional 5W30 rapidly shears down to a 5W20 anyway. So... What it the BITOG verdict?


Yes
 
I say use what's spec'd in the OM if still under warranty. If the manual gives you a menu, select according to your conditions. "Mountain out of molehills."
 
Originally Posted By: ThirdeYe
Originally Posted By: BlueOvalFitter
Originally Posted By: ThirdeYe
Although the engine is quite different, I've gone back and forth with 5W-30 and 5W-20 in my sister's Ford Windstar 3.8 with no ill-effects. Still runs great with well over 200,000 hard-driven miles.

The 3.8 engine is the same engine as my 4.2, only that the 4.2 is bored larger. It has always been specd 5W30 oil. I do the same thing with mine, switch back and forth with both weights.
But, I always am looking in my rear view mirror for the 5W20 police to pull me over when I am using a 5W30 oil.
crackmeup2.gif



That's strange that they had different requirements. On her van, it specifies 5W-20 in the owner's manual and on the oil filler cap. It's a 2001, FWIW.

According to my Ford Tech friend the Essex engine (3.8 & 4.2) were spec'd 5W30 oil up until the year 2000. Ford then spec'd 5W20 from then on. The clearances and tolerances had never changed on either engine as long as they had been in production all those years. So, ponder on the reason as to why the switch was made.
CAFE!

Oh, and Ford back spec'd 5W20 for all Essex engines prior to year 2000.

http://www.bing.com/search?q=3.8+and+4.2...cb5f7a21922e9b1
 
Originally Posted By: BlueOvalFitter
Originally Posted By: ThirdeYe
Although the engine is quite different, I've gone back and forth with 5W-30 and 5W-20 in my sister's Ford Windstar 3.8 with no ill-effects. Still runs great with well over 200,000 hard-driven miles.

The 3.8 engine is the same engine as my 4.2, only that the 4.2 is bored larger. It has always been specd 5W30 oil. I do the same thing with mine, switch back and forth with both weights.
But, I always am looking in my rear view mirror for the 5W20 police to pull me over when I am using a 5W30 oil.
crackmeup2.gif


My mistake. The bore remained the same but the stroke was longer. Ooops!
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Originally Posted By: BlueOvalFitter

According to my Ford Tech friend the Essex engine (3.8 & 4.2) were spec'd 5W30 oil up until the year 2000. Ford then spec'd 5W20 from then on. The clearances and tolerances had never changed on either engine as long as they had been in production all those years. So, ponder on the reason as to why the switch was made.
CAFE!

Oh, and Ford back spec'd 5W20 for all Essex engines prior to year 2000.

http://www.bing.com/search?q=3.8+and+4.2...cb5f7a21922e9b1


Oddly, in the 2000's, Ford's Cologne 4.0L V6 (Ranger, Explorer, Mustang) always remained 5w-30, never getting the "20" treatment.
 
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?
 
Originally Posted By: Nickdfresh
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?

This;

xkyr1v.jpg
 
OPEC? My mother's Grand Marquis was back-spec'd to 20. It's had 40, still using 30. No super-heated oil, no broken oil pumps, starts fine in the winter, good MPG.

The BITOG "Thin as possible, thick as necessary" mantra makes me laugh. I bet not one member that parrots that has gone down a grade to go as thin as possible.

Originally Posted By: Nickdfresh
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?
 
Originally Posted By: Nickdfresh
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?


I don't remember a lot of US cars specifying 10W-40 from the factory back in the day.

Most were spec'ed for 10W-30 or straight 30 weight back then.

Granted, we were a GM family.
 
Originally Posted By: Nickdfresh
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?

The same thing they say now.
wink.gif
Without CAFE (and similar regimes over the years), we'd still be stuck with breaker points and carbs, not to mention leaded gas.
 
Originally Posted By: Nickdfresh
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?


I dunno, but the SAE papers that I was reading (on microfiche) in the '80s were stating that the 10W-40s were horrid, shear prone, and created rubber like sludge under high speed conditions at times...I thought that they were replaced with 10W30s at the time, not 5s...they would have had similar amounts of the same VIIs that made the 10W40s bad...it was the failure of the 40s that (largely) got HTHS into the J300 tables...and had 0.5cst lower HTHS than say the 15W40s. (modern tables since 2012 have no delineation between 0W, 5W, 10W, and the 15W, 20W, 25W, reflecting that modern VIIS are so much better than in the bad old 10W40 days.

here is what policy makers and the NHTSA is saying

In short, buyers don't value fuel economy as much as society does, and need society (through Cafe) to gelp them along the decision path.

Low viscosity lubricants are number 1 on the decision making tree, as tehy are cheap (valued at $5 per vehicle install), can be applied without redesign, or retesting, and can be backspecced to other models and given credits for same.
 
Originally Posted By: Garak
Originally Posted By: Nickdfresh
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?

The same thing they say now.
wink.gif
Without CAFE (and similar regimes over the years), we'd still be stuck with breaker points and carbs, not to mention leaded gas.
What law made Ford stop building the Model T? Since only laws lead to innovation.
 
Originally Posted By: Garak
Originally Posted By: hatt
What law made Ford stop building the Model T? Since only laws lead to innovation.

Reductio ad absurdum?
No more than your post. Companies have been toying with things like fuel injection since the beginning. It certainly didn't start with CAFE. Laws did lead us to the abominations we saw in the late 70's and early 80's before we got decent workable low cost EFI.
 
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Yes, laws certainly led us to a lot of abominations. The carb that used to sit on my 4.9 L was a fine example of that. Nonetheless, my point was that the law did bring out certain innovations. Horsepower, fuel economy, and low cost of ownership have always helped sell vehicles. In addition to the garbage we saw on the market (i.e. those carbs), OPEC saw to some of that as readily as did any laws.

The automakers have been caught with their pants down several times over the years, by competition, the market, and the government. Don't forget the big collective cry that went out with the elimination of leaded gasoline. Automakers and pundits have cried about the sky falling far too often.
 
I have an 84 K10 with a 250. It would have been easier to envision the Higgs field vs figuring out that bird's nest.
 
The vacuum systems on carbed Hondas were a work worthy of Rube Goldberg himself.
Thankfully, the three bbl carbs were actually pretty easy to rebuild and rebuild kits were pretty inexpensive.
I'm also grateful that all of the vacuum operated thingies as well as all of the tubing were of high enough quality that I never had problems in the three carbed Hondas that we had.
I can't say the same of the vacuum system on the two 123 diesels I had, which actually used a vacuum pump, since diesels have no appreciable vacuum. The suction was in turn used for the brake booster, the door locks, the fuel filler flap lock and the fuel shutoff.
Lots of vacuum tubing running all over the car.
 
Originally Posted By: hatt
Originally Posted By: Garak
Originally Posted By: Nickdfresh
The CAFE conspiracy stuff is just boring at this point. What were people saying when manufacturers began going from 10W-40 to 5W-30?

The same thing they say now.
wink.gif
Without CAFE (and similar regimes over the years), we'd still be stuck with breaker points and carbs, not to mention leaded gas.
What law made Ford stop building the Model T? Since only laws lead to innovation.


The law of supply and demand.
Even at the giveaway prices Model Ts were moving at toward the end, nobody really wanted this slow and obsolete beast.
Had Ford not replaced the T with the slow and obsolete at introduction, but very stylish Model A, Ford would have joined most of the other automakers of the time in liquidation.
Ford would shortly ignite the first horsepower war with its flathead V-8, but that's another story.
 
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