Ford 4.6L DOHC oil opinions - it's been discussed

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Was surfing around on Ford 4.6L DOHC oil specs/opinions and came up with the following. Some of this stuff was new to me, though probably not to seasoned Bitogers. The Bitog thread at the end discusses much of the same points - 5 yrs ago. So just a refresher to those who haven't waded through it. There are 2V (SOHC), 3V (VVT), and 4V (DOHC) variants which I'm not exactly sure changes the oil discussion any....or if they're in Crown Vics and Grand Marquis, Lincolns, or Mustangs/Shelbys. I've owned 3 modulars since 2002 for a total of 350,000 miles, which doesn't mean squat compared to those who actually rebuild, test, or tear down these engines for a living. Just trying to learn a little more about them. The one thing I was looking for more information on was using a 0/5w-40 grade in my next summer time OCI. Still not 100% convinced on that despite some fleets using 15w-40's pretty reliably. I also didn't know there was a discussion about whether factory 6.0 qts (or 6.25-7.0 qts) was the truly "correct" fill for this engine. Some say the factory dipstick is off. And that so much oil is held up in the heads that 7 quarts is frequently used. I guess that's a potential reason to keep the the oil level near the full mark of 6 qts. at all times. Fwiw, whenever I do my oil changes I find that it takes 6.25 quarts to get it to the full line with a filter swap...and that doesn't count whatever oil is left up in the valve train. Comments from Scott Whitehead (10 yr Ford engine development engineer, AIX racer, Grand Am crew chief, and Nascar engineer). I think you'll understand that I can go into details here. And understand that I'm not saying that 5W-20 is not going to instantly do damage. But suffice it to say I've seen and been involved in a LOT of development on these motors, and my personal opinion is that I would never run 5W-20 in ANY modular motor. Regarding your "spec oil" comment, you need to look at what else governs this recommendation. SVTperformance DOHC thread Corner carvers on DOHC oil 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." 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. Trading a very small FE improvement in exchange for a large durability safety margin is not something I'm interested in doing" Nick McKinney on modulars John Tymensky, an ex-Ford engineer who was involved with the Modular's development and is also the premiere Modular race builder in the US recommends 30-weights. Scott Whitehead, lead power train engineer for the Mustang 4.6 3V and the Aviator 4.6 4V, recommends 30 weights and attests to lower wear observed in OEM durability testing when using 30-weight oils versus 20-weight. BITOG thread from 2011 on this same topi...r less filling?
 

69GTX

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I ran both conventional and synthetic 5w-20 on my current 2002 4.6L up to about 50K miles. The last 25K on 5w-30 synthetics. My previous 1997 4.6L saw 5w-30 conventional the entire life of 232K before a probable water pump/cooling issue took it out. Another Bitog thread - from 2013 In searching for 4.6L threads in the title on Bitog, nothing comes up, particularly anything more than 5 yrs old. Only way to find them is via Google searches.
 
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There's an excellent source of actual data here @ BiTOG from Jim Allen regarding modular oil selection. It'd behoove you to pull it up, look at the results, and also his conclusions (what oil he ultimately decided to go with after experimentation).
 
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Excellent post. Definitely confirms what I have believed for years, thank you. I have put countless thousands of hard, duty use miles on Crown Vic Police Interceptors. My department insisted on using Castrol dino 5w20 at 5k intervals without ever doing a UOA. Now 5k doesn't sound too bad, but when you add in extensive idle time and typical police use engine flogging, I am sure it was hard on them. Great engine no doubt the 4.6, they stood up to it. But they all exhibited extensive varnish visible through the fill hole well before 100k miles, and usually considerable oil consumption issues were present by 110 to 120k. They were also notably slower by then so I'd wager they were getting pretty tired by that point. Earlier this year I put a bottle of blue STP in mine on the sly right after the shop did a change. Consumption went from over 3 quarts an OCI to a half quart. Pretty significant. I always wondered how those engines would have done on a good 30 grade right from the start. A good 0w40 might be a better choice for them than a 5w40.
 
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You've definitely heard of the term confirmation bias in your line of work, right KCJeep? Throw out viscosity from the equation for a second. Can you think of any possible other reason why consumption would be high after 100k? (Hint...)
Originally Posted By: KCJeep
But they all exhibited extensive varnish visible
 
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I've seen several Modulars torn down after breaking a rod (rear drivers 9/10) or for timing chain/guide replacements. Most ran on 5w20 or 5w30. Out of the ones I've seen it makes little difference. My dad currently owns 4 modular engine trucks. A 3v 4.6 180k, a 2v 6.8 v10 with 200k, a 2v 4.6 with 275k and a 3V 5.4L with 165k all have always had 5w20. The ones I've torn down that use 5w20 are always the cleanest. 5w20 is not too thin for a modular. I ran 5w20 in a procharged 2002 Gt in the past as well. 20wt oils aren't "thin" they provide great lubricacion and excellent heat transfer. 20wts have been standard for 16 years in fords and Hondas....and cars today are running longer than ever. A thicker oil will not get any extra life out of a modular engine, especially a 15w40. The Most wear in an engine happens at startup especially on an OHC engine.
 
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I ran TropArtic 5W30 in my '93 DOHC 4.6 Mark VIII until it got totalled by hitting a deer. Mileage was over 150K, IIRC, without any problems.
 
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Where is the original article to the comments made by Ford, because all the links are to forums. so where did the comment originate from.
 
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There are boatloads of topics on several mustang forums relating to running higher then spek 5w20 in fords Coyote 5.0 V8 motors. From all the reading It seems inconclusive to me? Although I do run 5w30 in mine.
 

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Originally Posted By: Ramblejam
There's an excellent source of actual data here @ BiTOG from Jim Allen regarding modular oil selection. It'd behoove you to pull it up, look at the results, and also his conclusions (what oil he ultimately decided to go with after experimentation).
Thanks. I googled Jim Allen + 4.6L/modular and came up with several threads. Though most of the data seems to be on the 3V engines. Jim Allen on 4.6L 3V Have to agree with Camprunner that there are boatloads of threads on the topic and it's widely split on thicker vs. thinner (OEM). The fact that the recommended oil for the 4.6L was back specced thinner in 2000-2001 only adds more debate.
 
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Originally Posted By: 69GTX
Thanks. I googled Jim Allen + 4.6L/modular and came up with several threads. Though most of the data seems to be on the 3V engines.
 

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Originally Posted By: Tech819
Where is the original article to the comments made by Ford, because all the links are to forums. so where did the comment originate from.
The Ford TSB (Jan 14, 2002) that made the viscosity change to 5w-20 only mentions fuel economy as to the "why" which can be found in the link below. ISSUE: Ford Motor Company now recommends SAE 5W-20 viscosity grade for servicing most gasoline and flexible fueled vehicles. ACTION: All 2001 and 2002 vehicles where SAE 5W-20 is specified should be serviced at the recommended oil change intervals using SAE 5W-20. This oil is an improved formulation to improve fuel economy. Testing has validated this viscosity grade can be used in many previous model year vehicles. It is recommended ALL vehicles on the following Vehicle Application Listing be service with SAE 5W-20. All 2001-2002 vehicles other than those listed in the "Exception 2001 Vehicles" or "Exception 2002 Vehicles" chart are being filled with SAE 5W-20 motor oil at the factory and should also be serviced with SAE 5W-20 oil. Ford TSB information The other comments I listed above are from former Ford employees and not the company's official line. They are just opinions. If there's more official notices from Ford I'd like to see them too.
 
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Originally Posted By: 69GTX
The one thing I was looking for more information on was using a 0/5w-40 grade in my next summer time OCI. Still not 100% convinced on that despite some fleets using 15w-40's pretty reliably.
You'll be fine:
 
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Using any 0W or 5W qualified oil in any weather isn't going to cause any harm to this or any other engine. There will necessarily be some loss in fuel economy in using a much higher HTHS oil, but it won't be all that great and may not even be noticeable unless you're an OCD type and carefully calculate and log fuel economy for every tank, as I do. A bone stock Mod not developed for performance probably can't make enough power or heat its oil enough to have problems with a twenty grade. I've driven well maintained ~90K ex-OSP CVPIs and they ain't that strong. Even taking the comments from the former Ford folks to heart, the difference in potential engine life will be long eclipsed by the constant of vehicle life.
 

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Originally Posted By: Ramblejam
From what I read on Jim Allen's threads all his wear data is based on UOA's, not actual tear downs which is the only accurate way to determine engine overall wear and expected lifetime. The links above from McKinney relate to hundreds of head/cam tear downs. One has to figure Scott Whitehead did a large number of tear downs as well. I'd agree there aren't a rash of DOA's out there. Even Whitehead stated that the lighter oil would probably not lead to immediate damage...which could be taken to the point that most original owners would never be affected by it. Thanks Ramblejam for the info on the 3V engines being allowed an "upgrade" to 10w-40 if they "tick." I had read that today. But, there's no way to know if there are any lifetime trade-offs for that tick. Maybe Ford figured the "ticking" now on 20/30 grade oil would result in a failure much sooner than what might occur on 40 grade??? And would they make that same recommendation for 2V/4V engines if they ticked from some other cause? And Fdcg27's comment on vehicle life being shorter than engine life regardless of your oiling approach is probably true too for most of these 4.6L cars.
 
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We build alot of hi-po mod motors here, On the Dyno at full song a engines life can be measured in minutes using 5w20 hours with 5w30. and with 15w-40 we can leave it running in the test cell and take off for the weekend and that Mod is running perfect Monday morning, Do i dare to say those light oils are "CAFE Driven"
 
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Originally Posted By: ShotGun429
We build alot of hi-po mod motors here, On the Dyno at full song a engines life can be measured in minutes using 5w20 hours with 5w30. and with 15w-40 we can leave it running in the test cell and take off for the weekend and that Mod is running perfect Monday morning, Do i dare to say those light oils are "CAFE Driven"
...and there are V10's in medium-duty applications (class 4-6) that see "full song" use on a daily basis with 5w-20 in the sump, yet last for 250k+. As you said 69GTX, "it's been discussed." Xw-20 in these applications isn't a new thing, and we have many years now of real-world data/observation to go on when making a decision. For a stock engine in normal street usage, the OEM recommendation is appropriate.
 
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If the subject here is about excess engine wear with 20 wt oils then the UOAs don't show that. With the millions of engines using 20 wt oils, why don't we hear of mass engine failures over the last 15 years. This appears to be another "thick vs thin" post. Notice the UOA section on page 1 of the Merc GM 4.6 UOA using 5-20.
 
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Originally Posted By: 69GTX
I also didn't know there was a discussion about whether factory 6.0 qts (or 6.25-7.0 qts) was the truly "correct" fill for this engine. Some say the factory dipstick is off. And that so much oil is held up in the heads that 7 quarts is frequently used. I guess that's a potential reason to keep the the oil level near the full mark of 6 qts. at all times. Fwiw, whenever I do my oil changes I find that it takes 6.25 quarts to get it to the full line with a filter swap...and that doesn't count whatever oil is left up in the valve train.
With my 3V 5.4, I've found that the recommended fill of 7 quarts barely gets it above the add line on the dipstick. It takes another 3/4 quart to get to the full line, so I just put in 8 quarts.
 
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