5.0 (Coyote) Mustang Oil Viscosity Question

[AdRock]

Originally Posted By: ARCOgraphite
I heard that rumour about gear oil and fords - thats a dumb*&&%^ service manager decision. You shouldnt run hypoid gear lube in an engine! BTW. 90 weight gear lube is like a 40 grade oil, viscocity wise.


Several of the quotes I've seen have said that the decision to add that stuff came directly from Ford.

 

[Unleashedbeast]

The Aussie's use 5W-30 or thicker in the Ford modular, depending on application. Why? No CAFE laws there.

 

[demarpaint]

Originally Posted By: twsnnva
IMO, this also contradicts the "engineers know best" and the "it's been well tested" schools of thought. The 4.6L has been around for some 20 years vs the 1 year for the new 5.0. Originally, the 4.6L called for 5W-30. Sometime later Ford changed this to 5W-20. When that caused problems they put out a TSB for 10W-40. I doubt running 5W-20 is going to cause problems apart from the noise, but to me the noise in itself is a problem. Sure, it may not leave me stranded on the side of the road, but just like finding a new rock chip makes me cringe, so does going through a drive-through and hearing this noise.

I thank you all for your input. I do have my answer (5W-20 is the only oil spec'd for the new 5.0.) Now the real question. Do I give a heavier oil a shot and risk Ford giving me flack in the event I have engine issues? I guess I'm the only person that can answer that.


I totally understand where you'e coming from! I would take the car back to the dealer and either make them fix it, or get their blessing in writing to use a different viscosity oil, if in fact that does quiet things down.

With the newer technology, DI engines in some applications, and some of the newer engine designs, it has me scratching my head. How long does one wait after a new engine design comes down the line to have all the bugs worked out? I believe the engineers test these designs to a point, but I honestly believe the final testing is being passed on to the consumer, more and more than ever before.

 

[FL_Rob]

Originally Posted By: Unleashedbeast
The Aussie's use 5W-30 or thicker in the Ford modular, depending on application. Why? No CAFE laws there.


Thanks,I read the entire post to see if anyone would bring it up(cafe standards)and I'm glad you did,because whenever I do,I get bashed over the head.Some people believe that the engineers are allowed total control over specs.Regulation has alot to do with it.

 

[TFB1]

Originally Posted By: FL_Rob
Originally Posted By: Unleashedbeast
The Aussie's use 5W-30 or thicker in the Ford modular, depending on application. Why? No CAFE laws there.


Thanks,I read the entire post to see if anyone would bring it up(cafe standards)and I'm glad you did,because whenever I do,I get bashed over the head.Some people believe that the engineers are allowed total control over specs.Regulation has alot to do with it.


I suspect it's more of a corporate decision to eek out the last bit of MPG, while maintaining a reasonable engine life expectancy for Joe Average... I don't consider myself average, generally use 5W-30 in my everyday rides and M1 0W-40 in my Marauder...

 

[FZ1]

Originally Posted By: twsnnva
A few months ago I became the proud owner of a new Mustang GT with the new 5.0 powerplant. I realize this question is better suited to other Mustang owners, and have asked on a Mustang forum that I frequent but did not get any replies.

When preparing for the first oil change, I found it odd that the manual specified only 5W-20. Every other vehicle I've owned has had a recommended viscosity, but also listed others that could be used, depending on climate. This has allowed me to choose from several viscosities and use whatever happens to be on sale at the time. It also seems the new 5.0 is a fairly noisy motor in general (ticks and clicks) and I would like to try a heavier oil to see if that helps at all. Heavier oil made a huge difference in the amount of valvetrain noise my last modular Ford (4.6L 94' T-Bird) made. I've gone through my owners manual front to back and the only thing I see listed is 5w-20. Did I miss something in the manual, or is this really the only viscosity that can be used? I'm sure there are several other viscosities that would be just fine, but I don't want to have any problems should something go wrong that Ford could theoretically blame on incorrect oil. Thanks, Thomas.
Well,then,Hoss. Your course is clear,just use a good 5w-20 synthetic and change it per the manual's severe service schedule.What's so hard about that?

 

[ARCOgraphite]

Originally Posted By: AdRock
Originally Posted By: ARCOgraphite
I heard that rumour about gear oil and fords - thats a dumb*&&%^ service manager decision. You shouldnt run hypoid gear lube in an engine! BTW. 90 weight gear lube is like a 40 grade oil, viscocity wise.


Several of the quotes I've seen have said that the decision to add that stuff came directly from Ford.
Not a decision to be made AT ALL - you CANNOT run GL5 in an engine - gear lubes have wrong add pack, poor volatility and are good way to kill a motor. I would have to see a TSB - and them call them idiots. I call this internet foolishness. This is BITOG are you NOT aware you CANNOT run gear lube in an engine?! Jeepers! I read it on the internet 3rd hand - what a joke. - official rant completed (for now...)

 

[dparm]

IIRC Ford said to temporarily use it to see if it quieted the noise down, it was not a long-term solution.

 

[OVERKILL]

Originally Posted By: dparm
IIRC Ford said to temporarily use it to see if it quieted the noise down, it was not a long-term solution.


I recall a TSB stating 10w40 for the 3V phaser noises. I think that sounds a lot more reasonable and likely what is the case regarding this issue to see if heavier oil "fixes" the noise. The idea of running gear lube sounds insane, and in agreement with ARCO, contrived.

 

[edhackett]

Well it is the internet. 10W-40 does have the same viscosity at 100C as SAE 90 gear oil, therefore Ford is saying to use gear oil.

Ed

 

[AdRock]

Originally Posted By: ARCOgraphite
Originally Posted By: AdRock
Originally Posted By: ARCOgraphite
I heard that rumour about gear oil and fords - thats a dumb*&&%^ service manager decision. You shouldnt run hypoid gear lube in an engine! BTW. 90 weight gear lube is like a 40 grade oil, viscocity wise.


Several of the quotes I've seen have said that the decision to add that stuff came directly from Ford.
Not a decision to be made AT ALL - you CANNOT run GL5 in an engine - gear lubes have wrong add pack, poor volatility and are good way to kill a motor. I would have to see a TSB - and them call them idiots. I call this internet foolishness. This is BITOG are you NOT aware you CANNOT run gear lube in an engine?! Jeepers! I read it on the internet 3rd hand - what a joke. - official rant completed (for now...)


I tell ya what. YOU search different forums to find people posting up their experiences at the dealer and posting what they were told by Ford. I DID. I'd like to give you first hand info, howver I don't own one and I'm not going around to forums to get people to sign up here just to appease you.

 

[ItsMeHank]

Originally Posted By: twsnnva

When preparing for the first oil change, I found it odd that the manual specified only 5W-20. Every other vehicle I've owned has had a recommended viscosity, but also listed others that could be used, depending on climate. This has allowed me to choose from several viscosities and use whatever happens to be on sale at the time. It also seems the new 5.0 is a fairly noisy motor in general (ticks and clicks) and I would like to try a heavier oil to see if that helps at all.


Congrats on the sweet car! I had a '94 F150 with a 5.0 302 and I loved that thing. I'm sure the engines are have changed significantly so I wont comment from that perspective. However, my Acura TL is supposed to use 5w20. I was using PP 5w20 and I caught some Royal Purple 5w30 on sale for $4/qt. Needless to say I put that in my car and it was amazing how much it quieted down my valve train. My MPG went up noticeably as well (not just noise). I just bought some Royal Purple 5w20 to see if it was the viscosity or just the quality of the oil, but haven't put that in yet. According to many accounts of people that have used RP, it makes the engine run very smoothly.

After the RP 5w20, I'll buy Red Line to make a comparison. But RP 5w20 would probably be a good fit for you. (now let the RP haters step in!

)

 

[Unleashedbeast]

Originally Posted By: FL_Rob
Originally Posted By: Unleashedbeast
The Aussie's use 5W-30 or thicker in the Ford modular, depending on application. Why? No CAFE laws there.


Thanks,I read the entire post to see if anyone would bring it up(cafe standards)and I'm glad you did,because whenever I do,I get bashed over the head.Some people believe that the engineers are allowed total control over specs.Regulation has alot to do with it.


You are welcome, as I'm not afraid to tell the truth here.

Originally Posted By: TFB1
I suspect it's more of a corporate decision to eek out the last bit of MPG, while maintaining a reasonable engine life expectancy for Joe Average... I don't consider myself average, generally use 5W-30 in my everyday rides and M1 0W-40 in my Marauder...


DING DING DING!! Winner winner chicken dinner!

This is exactly why the auto manufactures did it. Read the quote below to better understand the penalties that are paid when they don't meet the "average mpg government standard".

Quote:
What is the penalty for not meeting CAFE requirements for any given model year (MY)?

The penalty for failing to meet CAFE standards recently increased from $5.00 to $5.50 per tenth of a mile per gallon for each tenth under the target value times the total volume of those vehicles manufactured for a given model year.

Since 1983, manufacturers have paid more than $500 million in civil penalties. Most European manufacturers regularly pay CAFE civil penalties ranging from less than $1 million to more than $20 million annually. Asian and domestic manufacturers have never paid a civil penalty.


What are CAFE credits?

Manufacturers can earn CAFE “credits” to offset deficiencies in their CAFE performances. Specifically, when the average fuel economy of either the passenger car or light truck fleet for a particular model year exceeds the established standard, the manufacturer earns credits. The amount of credit a manufacturer earns is determined by multiplying the tenths of a mile per gallon that the manufacturer exceeded the CAFE standard in that model year by the amount of vehicles they manufactured in that model year. These credits can be applied to any three consecutive model years immediately prior to or subsequent to the model year in which the credits are earned. The credits earned and applied to the model years prior to the model year for which the credits are earned are termed “carry back” credits, while those applied to model years subsequent to the model year in which the credits are earned are known as “carry forward” credits. Failure to exercise carry forward credits within the three years immediately following the year in which they are earned will result in the forfeiture of those credits. Credits cannot be passed between manufacturers or between fleets, e.g., from domestic passenger cars to light trucks.


So in their minds, improve MPG by 1/10th and save millions!

5W-20 = saving Ford, Honda, and Toyota millions of dollars every year. Who cares if it won't protect your engine as well as 5W-30, the engine will still make it throughout the warranty period on 5W-20.

To read more, click here CAFE Laws