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?
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?