Changing the oil


Kingman

GT Owner
Mark II Lifetime
Aug 11, 2006
4,061
Surf City, USA
Doesn't Gibbs Racing use Toyota's? :biggrin
 

bonehead

GT Owner
Mark II Lifetime
Aug 18, 2012
2,767
Houston, TX
Doesn't Gibbs Racing use Toyota's? :biggrin
Yeah, I guess they do. lol
But this stuff says specifically engineered for Ford Coyote and supercharged applications.
 

Kingman

GT Owner
Mark II Lifetime
Aug 11, 2006
4,061
Surf City, USA
Interesting....!

We've got guys here that know more about oil than I thought humanly possible. I wouldn't be surprised if they run a thorough analysis and report back before the day is out.
 

BIGFOOT

GT Owner
Jan 18, 2012
685
Northeast
Why can't Ford offer the 5/50 Syn in a 5 quart?
The GT is 9.5q and the 302-S is 12.5q,...if you can believe it.
 

twobjshelbys

GT Owner
Jul 26, 2010
5,061
Las Vegas, NV
This new Amsoil product seems to meet the WSS-M2C931-C spec for FGT, Mustang, etc:

http://www.amsoil.com/shop/by-equipment/automotive-and-light-truck/signature-series-motor-oils/sae-5w-50-signature-series-100-percent-synthetic-motor-oil/

APPLICATIONS
AMSOIL Signature Series Synthetic Motor Oil is excellent for use in all types of gasoline-fueled vehicles. It is recommended for all domestic and foreign vehicles requiring any of the listed performance specifications:

5W-50 (AMR): API SN, SM...; Ford WSS-M2C931-C (Mustang)
 

2112

Blue/white 06'
Mark II Lifetime
I don't think I've seen the Joe Gibbs product mentioned anywhere. Does anyone have experience with this?

View attachment 34955

http://www.drivenracingoil.com/dro/fr50-5w-50-synthetichtml/
I have used both their Dino break in oil and their synthetic in my 600 inch Ford marine engines. It is damn fine oil.

I change often (every 12 hours) so I don't send it in for analysis since I am not pushing it to it's life limits. I have used Mobil 1 and Amsoil, the Gibbs holds it's viscosity even after 10-12 hours of punishing use between 212 and 270 degrees, much at the higher limits. I see dropping oil pressure after 8 hours with Mobil 1 and 10 hours with Amsoil.

They get around the ZDDP thing by not being legal for street use....or at least that was case.
 

PeteK

GT Owner
Apr 18, 2014
1,205
Great Falls, VA
Does anyone know why Ford specifies 5W-50 viscosity? If the 5W spec is for winter use, and those who don't drive (or more importantly, start up) in really cold temps, we could substitute 15W-50, which is commonly available and much less $$. On the high end of the viscosity spec, the highest lubrication stress in the engine is the cam/follower interface (this is the primary need for ZDDP in conventional oils). But the cams in GT engines are not aggressive profiles (don't need to be with forced induction to get more air into the engine), and equivalent engines in the F-series trucks don't specify that high of viscosity. Furthermore, the Ford "modular engines" use roller followers, which greatly reduce the stress on the cam/follower interface (including our GT engines). In fact, Ford specifies 5W-20 for most engines produced since the early 2000's, including the other 5.4's, and 5W-30 for the Ecoboost engines. Why 50 for the GT engine?

Any experts here have insight into Ford's reasoning? Was it just overkill since they didn't have time for a full test/development cycle? TIA
 

jcthorne

GT Owner
Aug 30, 2011
792
Houston
All of the supercharged modulars have specified the higher viscosity for the high bearing loads on the main bearings. Especially the front bearing driving the SC.

The 5W cold viscosity is to prevent over tensioning of the cam drive chains at start up and drive off. This was a real problem for the early modulars in the early 90s. Many failed front cam bearings from using the wrong oil with too high initial viscosity at start up. And not just at very cold temps.
 
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MAD IN NC

Proud Owner/ BOD blah bla
Mark IV Lifetime
Feb 14, 2006
4,170
North Carolina
This new Amsoil product seems to meet the WSS-M2C931-C spec for FGT, Mustang, etc:

http://www.amsoil.com/shop/by-equipment/automotive-and-light-truck/signature-series-motor-oils/sae-5w-50-signature-series-100-percent-synthetic-motor-oil/

APPLICATIONS
AMSOIL Signature Series Synthetic Motor Oil is excellent for use in all types of gasoline-fueled vehicles. It is recommended for all domestic and foreign vehicles requiring any of the listed performance specifications:

5W-50 (AMR): API SN, SM...; Ford WSS-M2C931-C (Mustang)
I was waiting for Amsoil to step up..... took them long enough.

Q: Does anybody know what is the spec difference between the "A" 5w50 that was first produced for the FGT versus what FoMoCo sells today as 5w50 known as the "C" spec'd? Then, will the Amsoil fit the bill of the "A" spec?

I'm hoping IndyGt the answer man should know...
 
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Indy GT

Yea, I got one...too
Mark IV Lifetime
Jan 14, 2006
2,403
Greenwood, IN
Does anyone know why Ford specifies 5W-50 viscosity. Any experts here have insight into Ford's reasoning? Was it just overkill since they didn't have time for a full test/development cycle? TIA
Pete,

Not an expert here but have talked to a number of engineer’s on the engine team. I believe jcthorne adequately answered your oil question on the high and low end viscosity ranges Ford selected for our GT engines.

And I take issue with your assumption Ford “didn’t have time for a full test/development cycle”. Even though the development time for the FGT was abbreviated (tremendously) the engine team really did do a full design/development cycle on our unique 5.4L dry sump engine. Surely it shares features with the other 5.4 modular family but the engine design is unique to the FGT. See SAE publication 2004-01-1252 for some of the technical details that Ford could make public. I am certain there were proprietary details as well.

Ford introduced the Motorcraft Full Synthetic 5W-50 oil (WSS-M2C931-A, black cap) specifically “designed, engineered and recommended for use in the Ford GT”. It was developed as a singular target oil for the GT. The oil development (which I believe was originally sourced from Conoco-Phillips) paralleled the engine development and all the OE durability, hot/cold testing was done with this oil.

In speaking with some of the team members after the WSS-M2C931-B (gold cap) version came out which removed the ZDDP additive due to EPA instance for catalyst fouling, the GT team was caught off guard. They did not know the ZDDP-less oil had been released and how the removal of this additive might impact any warranty issues. I am told that to Ford’s credit they pulled a line engine and reran the whole engine durability test cycle on the new –B oil just to make sure there were no issues which might pop up without the ZDDP additive in the oil. The engine successfully passed this test.

Q: Does anybody know what is the spec difference between the "A" 5w50 that was first produced for the FGT versus what FoMoCo sells today as 5w50 known as the "C" spec'd? Then, will the Amsoil fit the bill of the "A" spec?
I'm hoping IndyGt the answer man should know...
Hi Mad.:biggrin
I still have a few cases of the Motorcraft Oil in my basement since both the Boss and GT use the same oil. My cases are all the –B version of the WSS spec. I did not know that Ford (or their supplier) had rolled to a third –C level for the oil. Will be traveling up to Detroit shortly and I will see if I can learn what caused the oil spec to be revised yet again. Does the -C spec oil have yet another color cap?
 

Xcentric

GT Owner
Mark II Lifetime
Jul 9, 2012
5,208
Myakka City, Florida
As Indy GT might say, "The search engine is your friend."

jcthorne's treatise on Rotella T6 convinced me of its superiority to the reformulated Motorcraft oil.

And you can buy it in gallons cheap on Amazon.
 

BlackICE

GT Owner
Nov 2, 2005
1,412
SF Bay Area in California
If you can safely start the car in 0 degree with 5w then wouldn't using a 10w or 15w be no worse in 70F?
 

Bart Carter

GT Owner
Mar 12, 2006
272
Las Vegas
If you can safely start the car in 0 degree with 5w then wouldn't using a 10w or 15w be no worse in 70F?
The lower the oil weight, the faster the pressure build throughout the engine. The pressure build is what you want.

As the engine warms up, the "multi" weight adjusts accordingly.
 

PeteK

GT Owner
Apr 18, 2014
1,205
Great Falls, VA
JcThorne and Indy: Thanks for the responses. I'll search the archives for more on JC's dissertation.
 

PeteK

GT Owner
Apr 18, 2014
1,205
Great Falls, VA
Okay I searched the archives and found JC's discussion on Rotella and Motorcraft viscosity breakdown in this thread, but not any other threads on the topic of oil viscosity. Did I miss anything? I'm still not closing all the gaps in my knowledge of tribology versus what has been written here.
 

SMOKDU

GT Owner
Dec 17, 2011
402
The lower the oil weight, the faster the pressure build throughout the engine. The pressure build is what you want.

As the engine warms up, the "multi" weight adjusts accordingly.
Not to change topic but during the cash for clunkers when we had to blow up motors we added tires shine and ran the car. It lived. What's the rating on that ws 40 or wheel shine 40 lol. Ok back to topic.
 

jcthorne

GT Owner
Aug 30, 2011
792
Houston
Okay I searched the archives and found JC's discussion on Rotella and Motorcraft viscosity breakdown in this thread, but not any other threads on the topic of oil viscosity. Did I miss anything? I'm still not closing all the gaps in my knowledge of tribology versus what has been written here.
Not sure what it is you are still looking for.
 

Indy GT

Yea, I got one...too
Mark IV Lifetime
Jan 14, 2006
2,403
Greenwood, IN
Okay I searched the archives and found JC's discussion on Rotella and Motorcraft viscosity breakdown in this thread, but not any other threads on the topic of oil viscosity. Did I miss anything? I'm still not closing all the gaps in my knowledge of tribology versus what has been written here.
Pete,

I do think JC’s discussion on Rotella is very convincing especially if that oil continues to be classified as a “truck or diesel” oil and thus is allowed the ZDDP additive. Taking his advice as very logical based, supplemented with measured data, I now use T5 Rotella in my one remaining vehicle which is not using a full synthetic oil recommended by the manufacturer.

Good that you searched the Forum on the topic but perhaps there is less specific information as to “oil viscosity” genealogy discussions and more of well I can buy XXX product at WalMart/Pep boys so why do I have to spend YYY per quart to use the recommended Motorcraft oil. And my engine just purrs using the XXX oil.

Owners certainly can use whatever oils they want to in their engines. No argument here. Go for whatever you feel comfortable using; it’s your engine. But for me (and only me) by using the oil recommended by Ford for our GT engine, knowing this oil was developed alongside the engine, used in all the development/durability testing and continues to undergo batch spot checking by the QA team at Ford to insure constant formulation, it is just one thing I do not worry or think about.

So what “gaps in my knowledge of tribology” still remain?
 

Xcentric

GT Owner
Mark II Lifetime
Jul 9, 2012
5,208
Myakka City, Florida
So what “gaps in my knowledge of tribology” still remain?
Kirk_surrounded_by_Tribbles.jpg
 

BlackICE

GT Owner
Nov 2, 2005
1,412
SF Bay Area in California
A strait 50w oil would be the best after you add a oil tank heater and heat the oil to 160F before starting the engine. :lol