2v Mustang GTs: What oil do you run??

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I recently picked up a 2002 Mustang GT smile in great shape with 92,xxx miles on it. 4.6 liter SOHC 16 valve engine coupled with a 5 speed manual. I changed the oil the other day, and put in some of the new Pennzoil Ultra 5w20 with an FL-820s filter. I'm curious what other bitog users run in their 2v 4.6 Ford applications, but mainly the 1999-2004 Mustang GTs. Do you run 20wt or 30wt? What works for you?
 
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I have an '02 GT also, I run a 5w30. The spec for it is 5w20 but Ford only did that for CAFE. These 4.6's were originally spec'd 5w30. My personal preference for the car is Mobil1 5w30HM. The engine has 100k hard miles on it and at this point seems to like the HM oil a little better.
 
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Originally Posted By: AdRock
I have an '02 GT also, I run a 5w30. The spec for it is 5w20 but Ford only did that for CAFE. These 4.6's were originally spec'd 5w30.
Can you cite an application where the 4.6 2v was spec'd for 5w30? Also, if there is any credible information indicating there were no revisions to the engine which would necessitate the change to 5w20, I would be interested in that as well.
 
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Originally Posted By: fsdork
Can you cite an application where the 4.6 2v was spec'd for 5w30? Also, if there is any credible information indicating there were no revisions to the engine which would necessitate the change to 5w20, I would be interested in that as well.
While it's not in a Mustang, I've got a 5.4 2V F250 that says to use 5W-30 on the engine spec label that's in the engine compartment. I use 5W-30 in the summer and 5W-20 in the winter. I just changed oil in it about an hour ago and I'll put enough miles on it to comfortably still use 5W-30. I poured in TropArtic.
 
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@ the OP: The Ford modular motors are not picky about oil. 5W-20 or 5W-30 it won't even notice the difference. Many municipalities and fleets even run 15W-40 in them with no apparent issues, although I wouldn't do that in winter in the Northern states or the Canada. I run PP 5W-30 in my Marauder as it's supercharged, but I put MC 5W-20 in my 2000 Grandpa-mobile and it likes it just fine.
 
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2002 GT - Amsoil XL 5W-20 with the Amsoil fllter. Annual OCI is about 2,500 miles. It's certainly overkill, but that's what I use.
 
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Originally Posted By: fsdork
Originally Posted By: AdRock
I have an '02 GT also, I run a 5w30. The spec for it is 5w20 but Ford only did that for CAFE. These 4.6's were originally spec'd 5w30.
Can you cite an application where the 4.6 2v was spec'd for 5w30? Also, if there is any credible information indicating there were no revisions to the engine which would necessitate the change to 5w20, I would be interested in that as well.
Here's a post from Corral.net that explains things and has quotes from Ford employees.
Quote:
Many people have provided valuable information on the proper weight oil to run in our modular engines so I thought I'd condense it into a single post. The bottom line is, we really shouldn’t be running 5w20. The switch from 5w30 in 1999 to 5w20 in 2001 (on identical engines) had nothing to do with wear or reliability issues and everything to do with Ford saving a few bucks by meeting CAFE standards. At the time Ford was fined $5.50 for every 1/10th of a MPG under the target average of 27.5 MPG for every vehicle manufactured. To help meet the target Ford changed from 5w30 to 5w20 and was able to improve mileage by 1/16th of a MPG and meet their goals. Here is a quote from one of Fords Product Design Engineers: Mike Riley, Product Design Engineer with Ford Motor Company: Quote: "Moving to 5w20 was driven by ... CAFE requirements. The company believes the switch to lighter viscosity 5w20 oils will reduce carbon dioxide emissions by 190,000 metric tons a year and reduce US fuel consumption by over 21,000,000 gallons a year." While most people understand the main function of oil is to protect the engine, Ford's only concern in that respect is that the engine survives the warranty period. I especially appreciate Scott Whiteheads insight on this topic. He worked for Ford testing different oils in modular engines and here is what he had to say: Scott Whitehead - Engine Development Systems Engineer, Ford Motor Company: Quote: "I've seen the dyno testing. I've probably looked at several hundred engines disassembled and spread out on inspection tables. And I've been involved in testing to resolve issues where varying the oil viscosity was part of the test. Please do not put 5w-20 or less into a mod motor. Please. This is especially true in 4v motors. 5W-30 is probably a good oil for the street with mixed temperatures." Ford Racing Group apparently feels the same way: FRPP Group: Quote: "DO NOT go back to using 5w-20" Real world experience seems to back up the advice of these experts too. Some of the best data from the modular community has come from Nick McKinney: Quote: "I have said it a few times now, heavier oil has better protection especially in the cam bores. ---I get 2-3 sets of modular heads a week through here, and any lay person just from looking would pick the 500,000 mile cores run on 15W-40 diesel spec all their lives over the typical Mustang head run 50,000 miles on the light stuff" Fleets typically run their vehicles 250,000 to 500,000 miles! I've heard Nicks experience echoed several times by fleet managers. They wouldn’t run a 5w-20 oil for one minute. There have been concerns over bearing tolerances and lash adjuster pump up with heavier weight oils but these are largely overblown. Bearings tolerances haven’t changed since the 60's and much of the small difference found at the crank bearings is because of the aluminum blocks different expansion rate. A reality check for those concerned is the fact that while the 01+ modulars were spec'd to 5w-20 oil, the exact same engine pre 01 was spec'd with 5W-30. When Shelby modifies the 4.6's he covers the 5w-20 spec sticker under the hood with a 5w-30 spec sticker. In Australia all their modulars are spec'd for 5w-30 and higher because they have no CAFE standards. And the GT500/GT's with the exact same bearing clearances are spec'd for 5w-50w oil.
 
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austinlunsford

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Originally Posted By: CHARLIEBRONSON21
Is it a red convertible? Anyways. Before I turned mine into a semi race car I ran 5W30 whatever. Never had an issue.
Haha no, an Oxford white coupe!
 

austinlunsford

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Good info here, guys! Thanks a lot! I will probably just keep the 20wt in there through winter and put either 20wt or 30wt in it going forward depending on what is in my stash.
 
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My friend had a 96 GT (same 4.6 I'm guessing) and ran 10W30 mineral all it's life. Had a lil over 300,000 miles on it till it got rear ended one night and totaled.
 

austinlunsford

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Originally Posted By: aquariuscsm
My friend had a 96 GT (same 4.6 I'm guessing) and ran 10W30 mineral all it's life. Had a lil over 300,000 miles on it till it got rear ended one night and totaled.
That's unfortunate for him. Yes, the motor is the same in a lot of ways, but the heads, intake, cams, and few other things are different when compared to mine. I'm thinking now that these motors can run just about anything and not complain!
 
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My last fill in my former 03 GT was Mobil 1 0w20 AFE. It performed every bit as well as the M1 5w20 plus quieter at start up. I gave it some hard runs too. I didn't have it in during the winter but it is my oil of choice for the 4.6.
 
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