5W20 in engines calling for 5W30

[farrarfan1]

I was pondering the idea of using 5W20 in my wifes 04 Concorde 2.7L engine, at least in the winter. I emailed Chrysler and asked for their opinion on this, specifically asking about engine durability and if 5W20 would satisfy the warranty requirements.Their response was "stick with 5W30, using 5W20 would result in poor gas mileage." Somehow this doesn't make sense to me. If they said using 5W20 would cause the engine to fuse itself into a solid mass of metal I guess I would have said OK, won't use it. But poor gas mileage? If any of the oil guru's here have any opinions, pro or con, on using 5W20 in this engine or any other one that isn't "spec'd" for that weight oil might be helpful Thanks in advance.

 

[luvs2drive]

Cause poor mileage!

If anything it might be too thin and your car. It might, consume a bit of oil. Other than that, a thinner oil would net you better mileage. Most 0W-20's are a more shear stable oil though.

 

[Patman]

I see no harm in using a 5w20 oil in the wintertime in a car that calls for 5w30, at least for those doing short trips. Since the oil never gets up to full operating temp when you're doing short trips, it's not like you'd actually be running an oil that is too thin for the engine. I've always felt that 0w20 and 5w20 oils were the perfect viscosity for short trip driving in winter.

 

[pmt]

I'm an old timer - I used to use straight weight SAE 10W every winter and sometimes maybe a little too far into the Spring. But my small block Chevy's always went 250,000 mi without major work. I'm not at all afraid to run 5W-20 in winter.

 

[luvs2drive]

Hmm, interesting info guys! I just keep learning new stuff all the time.

 

[Johnny]

It's my understanding that Chrysler is going to start recommending 5W20 in 2005 for the 2006 cars. I guess if they think it won't work now, that they are in the process of making some major engine changes just like Ford did.

 

[Al]

Well-after reading the many UOA's I have come to see that 20 wt and 30 wt oils are fine. And previously I was leaning to 40 wt oil. Bear in mind that 20 wt oils are on the higher end of the 20 wt. scale and oils like Mobil 1 are at the lower end of the 30 wt scale.

I would maybe say to go with a 50/50 mix of 20wt/30wt. do a UOA and go from there. That's what I am doing right now.

 

[pmt]

Many Ford experts claim that the clearances in the 4.6L V-8 have not changed from the year of introduction (maybe around 1994 - I'm guessing) until the present time. But the oil recommendation has moved from 10W-30 to 5W-30 to 5W-20. Could some Ford guys chime in here to tell me if I'm correct? Thanks.

 

[farrarfan1]

Thanks for the responses. I may be looking for a solution to a problem that doesn't exist, but after reading all the good results obtained with 5W20 it seems logical that it might work in other engines that maybe aren't subjected to real extreme driving conditons. I didn't ask Chrysler for a clarification on the poor gas mileage response, sort of figured it was like not liking the service you get from a pimply faced 16 year old at Mcdonald, and when you ask for the manager you get a 17 year old pimply faced kid. Might give it a try this winter and see what happens.

 

[G-MAN]

Take a look at my UOA where I used Pennzoil 5w20 in my Chrysler 3.5, which is spec'd for 10w30. The wear numbers were OUTSTANDING, and this oil wasn't just used in the winter, it saw quite a bit of HOT weather driving, too.

 

[Motorbike]

IF

the engine clearance was too loose and if

the oil saw temporary viscosity shear and if

because of that the oil was running on the boundry additives I could see a loss of fuel mileage because of friction

Ford really kicked up the oil pressure for the 20wt oil and changed bearing metalurgy for it as well .

The thing about these SL 30wts is when they shear it is not always down to a high 20wt and they don't immediatley shear offering 30wt protection for some time .

The new API SM 5w-30's should prove more shear stable . It remains to be seen though . They will have better oxidative stability from the better base oils but when was the last time we saw a low cost 30 wt get condemned for thickening up too much ?

We just don't run them enough miles

 

[Ken2]

quote:

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Originally posted by pmt:
Many Ford experts claim that the clearances in the 4.6L V-8 have not changed from the year of introduction (maybe around 1994 - I'm guessing) until the present time. But the oil recommendation has moved from 10W-30 to 5W-30 to 5W-20. Could some Ford guys chime in here to tell me if I'm correct? Thanks.

---

Oils have gotten better, and the pressure to improve fuel mileage has increased. Even a fraction of a MPG makes a difference on Ford's C.A.F.E. penalty payments and the country's oil import bill.


Ken

 

[Johnny]

Motorbike: Thanks for the info on the oil pressure and bearings. I was not aware of that. I was trying to make a joke about Ford doing anything different to their engines. I learn something new everytime I log in to this board. THANKS!

 

[97tbird]

quote:

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Originally posted by Motorbike:

Ford really kicked up the oil pressure for the 20wt oil and changed bearing metalurgy for it as well .

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Motorbike,
do you know WHEN(year) Ford changed these things in the 4.6L? before or after 1997?
Thanks in advance.

 

[thrace]

The 2.7 may be more likely to develop sludge than some others. See this article. http://www.babcox.com/editorial/ar/eb40430.htm
See under rod bearing failures.
"temperatures are pretty high (the high speed fan comes on at 230º) and the engine only holds four and a half quarts of oil, so the oil gets too hot and it begins to break down. Multi-viscosity oils revert back to their base viscosity if they're subjected to too much heat and pressure, so a 5W-20 may well revert back to a 10W or even a 5W viscosity if it's "abused," and that's just not good enough for these engines. "

If it were mine, I would follow exactly the owners manual except if using dino, change oil every 3000 miles, or use synthetic oil.

 

[Motorbike]

quote:

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Originally posted by 97tbird:

quote:

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Originally posted by Motorbike:

Ford really kicked up the oil pressure for the 20wt oil and changed bearing metalurgy for it as well .

---

Motorbike,
do you know WHEN(year) Ford changed these things in the 4.6L? before or after 1997?
Thanks in advance.

---

Nope . Probably when they started requiring 20wt.

Some of that info is hard to find like various oil pressure limits of different models. I would be curious to see early 4.6 engine oil analysis's to look for lead or to find out about the exact metalurgy in the early engines and or to see who was jumping up and down about zero lead in the reports

But too much work and if it don't go fast ..... I don't dig in to learn so much

And if dinner were ready I'd likely not be here this time of the day . LOL

 

[Ray H]

quote:

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Originally posted by Johnny:
It's my understanding that Chrysler is going to start recommending 5W20 in 2005 for the 2006 cars.

---

I recently looked at a 2004 Chrysler 300C in the dealer's showroom with the hood open. There in plain view was a factory sticker to use 5W-20. This is the hemi motor. With that in mind, and after reading several VERY favorable recent 5W-20 UOAs on Exxon Superflow 5W-20, I purchased 5 quarts of the stuff for my Hyundai V6's recent oil change. However, I got cold feet and returned it. With a 100,000 mile warranty, I just have too much to lose in case something breaks - don't need the hassles if Hyundai were to challenge my choice. (Before anyone asks how they'd know, the viscosity is on my receipts, and you can darn well bet the company would want to see some evidence I was changing according to schedule and specified viscosity grade before they'd fix a motor for free.)

 

[farrarfan1]

Thanks for the info THRACE. I've found a couple other articles about the sludging problem with this motor. Of course that was after I bought it. Just bought the car in July, it holds 5 quarts of oil. I plan on sticking with what the manual calls for which is 3k/3months whichever comes first. From what I've been able to find this was mostly a problem with pre-2002 engines. At least I hope so.

 

[G-MAN]

quote:

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Originally posted by Johnny:
Motorbike: Thanks for the info on the oil pressure and bearings.

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Johnny, Ford engineers have stated that nothing was done to their engines to "prepare" them for 5w20. That is why they could retroactively spec 5w20 for all modular engines back to 1992. Even the "old tech" small block 5.0 pushrod engines are now retroactively spec's for 5w20 back to the early 90s.

This rumor that something had to be done at the design level in order to safely run 5w20 is just that: a rumor.

 

[MNgopher]

quote:

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Originally posted by G-Man II:

quote:

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Originally posted by Johnny:
Motorbike: Thanks for the info on the oil pressure and bearings.

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Johnny, Ford engineers have stated that nothing was done to their engines to "prepare" them for 5w20. That is why they could retroactively spec 5w20 for all modular engines back to 1992. Even the "old tech" small block 5.0 pushrod engines are now retroactively spec's for 5w20 back to the early 90s.

This rumor that something had to be done at the design level in order to safely run 5w20 is just that: a rumor.

---

As dee pas I have dug, this seems to be correct. Even the earliest 4.6 motors share the same bearing metallurgy. Nothing has changed between the '97 motors in the F150 that required 5w30 and the later versions that called for 5w20. All run high oil pressures, regardless of model year.