I have a '94 Explorer Sport, v6 with 205,000 miles on it. It is NOT retrospec'd to use 5w20 like some other Ford models of its vintage. I've been reading a lot of Dr. Haas's material on the benefit of running very thin oils, and have decided to give it a try. I'm changing my oil this weekend with MC 5w20 and will run it for 5k miles. Anyone see any problems with this? I don't believe that 5w20s are too thin where spec'd, but could they be too thin for this application? BTW, a drive with a light foot in the heat and humidity of Savannah, GA, 50/50 highway and city.
1994 v6 Explorer...5w20 too thin?
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I wouldn't recommend it. Although I have no idea why Ford did not back-spec this engine to 5w20.
The other side of the argument is that most 5w20's are just below the 5w30 range in terms of operating viscosity. And, more than a few dino 5w30's have sheared down to a 5w20 during normal service anyways.
You probably won't hurt anything but I'd wait and see what everyone else says.
The other side of the argument is that most 5w20's are just below the 5w30 range in terms of operating viscosity. And, more than a few dino 5w30's have sheared down to a 5w20 during normal service anyways.
You probably won't hurt anything but I'd wait and see what everyone else says.
IIRC the pump in the Ford 4.0L was not designed for 5W20 oils which is why Ford didn't back spec them to 5W20. I would continue with 5W30, and leave well enough alone. JMO
Lets see, trust Ford Motor Co. or some guy on a forum??? Hmmm.
U Cant get around the law of physics, flow dynanics, tribology etc; a moderate viscosity has its place - esp in rod big ends and piston walls. The oil pump has very little capability to provide decelerative load and shock load support v. "the squish out time" in u-sec of a higher viscosity fluid in a shock-loaded bearing journal. The oil pressure seen in the bearing is only a matter of a few lbs - it just puts the oil there - oil pressure doesnt really support the bearing.
U Cant get around the law of physics, flow dynanics, tribology etc; a moderate viscosity has its place - esp in rod big ends and piston walls. The oil pump has very little capability to provide decelerative load and shock load support v. "the squish out time" in u-sec of a higher viscosity fluid in a shock-loaded bearing journal. The oil pressure seen in the bearing is only a matter of a few lbs - it just puts the oil there - oil pressure doesnt really support the bearing.
Yes too thin
Originally Posted By: stranger706
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The other side of the argument is that most 5w20's are just below the 5w30 range in terms of operating viscosity. And, more than a few dino 5w30's have sheared down to a 5w20 during normal service anyways.
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That is a poor argument. 5w-30 are shearing down to SAE20 range because they are unstable garbage loaded with polymeric viscosity improvers. This "shear out of range" is unacceptable and will get you a wave bye-bye from the new car warranty if you develop engine problems, API or no API. That is failed oil.
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The other side of the argument is that most 5w20's are just below the 5w30 range in terms of operating viscosity. And, more than a few dino 5w30's have sheared down to a 5w20 during normal service anyways.
...
That is a poor argument. 5w-30 are shearing down to SAE20 range because they are unstable garbage loaded with polymeric viscosity improvers. This "shear out of range" is unacceptable and will get you a wave bye-bye from the new car warranty if you develop engine problems, API or no API. That is failed oil.
I would never go against (thinner than, no problem going thicker) an OEM oil requirement, as I've always ran 5w30 in our Explorer, but here are my thoughts.
With most 5w30's being 10.xx CST at 100C, and most 5w20's being 8.xx CST at 100C, is ~2 CST's really going to make that much difference?
With most 5w30's being 10.xx CST at 100C, and most 5w20's being 8.xx CST at 100C, is ~2 CST's really going to make that much difference?
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Ford did not back spec this engine for a reason.
Dr. Haas can afford the potential price of experimentation
Can you?
I'd probably have 15W-40 in this thing in Georgia, but that's just me.
Having said this, I doubt that 5K on this oil will do any real harm.
I would not make a habit of it, particularly after 205K.
You don't live in anything like a cool climate, light foot or not.
Dr. Haas can afford the potential price of experimentation
Can you?
I'd probably have 15W-40 in this thing in Georgia, but that's just me.
Having said this, I doubt that 5K on this oil will do any real harm.
I would not make a habit of it, particularly after 205K.
You don't live in anything like a cool climate, light foot or not.
Originally Posted By: demarpaint
IIRC the pump in the Ford 4.0L was not designed for 5W20 oils which is why Ford didn't back spec them to 5W20. I would continue with 5W30, and leave well enough alone. JMO
+1 Specs for 5w30, that's what I'd use in the 4.0L.
IIRC the pump in the Ford 4.0L was not designed for 5W20 oils which is why Ford didn't back spec them to 5W20. I would continue with 5W30, and leave well enough alone. JMO
+1 Specs for 5w30, that's what I'd use in the 4.0L.
If you do try, let me know how it works out. Been curious about this for a while, but i'll continue to use 5w30 maxlife. 5w20 in my motor will probably leak like a sieve through my already leaky main.
Go for it . It is surprising that you engine lasted as long as it did with out thin oil.
Originally Posted By: ryansmith219
I don't believe that 5w20s are too thin where spec'd, but could they be too thin for this application?
Yours is NOT spec'd and demarpaint told you why.
If its been running fine for 205k miles with the 5w30 [which its supposed to have] I would just leave well enough alone.
I don't believe that 5w20s are too thin where spec'd, but could they be too thin for this application?
Yours is NOT spec'd and demarpaint told you why.
If its been running fine for 205k miles with the 5w30 [which its supposed to have] I would just leave well enough alone.
Dude! [censored] CHUK? Anyways it ain't mine so do what you want. Though I think some of us take the 5w20 thing to far. Common sense says 10w30 in GA. If it ain't your primary ride and you don't care if it blows up then do whatever you want.
It prolly won't blow up. And if it does it prolly ain't cause of the oil. Especially if you drive with a light foot. You prolly get away with straight 10w if you poke around. Nah mean?
If you really wanna see if the 5w20 is right for this old motor then pour it in and take it to the drag strip. If you wouldn't run it at the drag strip or baja then why would you wanna use it?
It prolly won't blow up. And if it does it prolly ain't cause of the oil. Especially if you drive with a light foot. You prolly get away with straight 10w if you poke around. Nah mean?
If you really wanna see if the 5w20 is right for this old motor then pour it in and take it to the drag strip. If you wouldn't run it at the drag strip or baja then why would you wanna use it?
Ford must have had what they thought was good reason to pick out this one engine not to back-spec to 5W20. One reason might have been that this is a German engine, and most German engines spec a Xw30 or Xw40 engine oil.
Other than wanting to experiment on an old engine that you feel you have gotten your money's worth out of, I see no reason to change to a thinner oil at this high mileage. I would personally be considering a change to a good 5W40 at this stage of engine life.
Other than wanting to experiment on an old engine that you feel you have gotten your money's worth out of, I see no reason to change to a thinner oil at this high mileage. I would personally be considering a change to a good 5W40 at this stage of engine life.
IIRC it has been discussed on this board, the 4.0L Ford's pump wasn't designed to handle 5W20 oil. Other Fords like my 93 Vulcan were back spec'd to 5W20, 92 and back weren't because of lifter design I think.
If it were my 4.0L Explorer I'd stick with 5W30, why tempt fate? JMO
If it were my 4.0L Explorer I'd stick with 5W30, why tempt fate? JMO
Originally Posted By: addyguy
In the warmth down there, no need even for a 5W-30. I'd use a good 10W-30 oil, and get the benefit of slightly more shear stability.
They both weigh the same when the engine is at operating temp. The 5w has the benefit of fast lubrication on start-up. Stick with 5w-30 or give 0w-30 a try which is exactly what I am planning to do this weekend.
In the warmth down there, no need even for a 5W-30. I'd use a good 10W-30 oil, and get the benefit of slightly more shear stability.
They both weigh the same when the engine is at operating temp. The 5w has the benefit of fast lubrication on start-up. Stick with 5w-30 or give 0w-30 a try which is exactly what I am planning to do this weekend.
Originally Posted By: Mustang Man
Originally Posted By: addyguy
In the warmth down there, no need even for a 5W-30. I'd use a good 10W-30 oil, and get the benefit of slightly more shear stability.
They both weigh [about] the same when the engine is at operating temp. The 5w has the benefit of fast lubrication on start-up. Stick with 5w-30 or give 0w-30 a try which is exactly what I am planning to do this weekend.
For example, Mobil 1 regular synthetic 5w-30 is a little thicker than their regular synthetic 10w-30 at operating temperatures.
Originally Posted By: addyguy
In the warmth down there, no need even for a 5W-30. I'd use a good 10W-30 oil, and get the benefit of slightly more shear stability.
They both weigh [about] the same when the engine is at operating temp. The 5w has the benefit of fast lubrication on start-up. Stick with 5w-30 or give 0w-30 a try which is exactly what I am planning to do this weekend.
For example, Mobil 1 regular synthetic 5w-30 is a little thicker than their regular synthetic 10w-30 at operating temperatures.
Here's what you do, if you really want the benefits of a 5W20 without the risk of using a 5W20:
Look for the thinnest 30wt oil you can find. The one that comes to mind is Chevron Supreme 10W30 or Havoline 10W30. If my memory is correct, those two are 9.7cst @100C. This is within spitting distance of being a 20wt oil. Costco usually has Chevron, and Advance AutoParts has Havoline.
Good Luck!
Look for the thinnest 30wt oil you can find. The one that comes to mind is Chevron Supreme 10W30 or Havoline 10W30. If my memory is correct, those two are 9.7cst @100C. This is within spitting distance of being a 20wt oil. Costco usually has Chevron, and Advance AutoParts has Havoline.
Good Luck!
stick with the 30 weight oils, the guys who say Ford did not back spec the engine are correct, there is a Ford document out that states the oil pump could not be modified on the German V6 and 5w30 should be used, with that many miles I would even consider using a heavy 30 like Rotella T 10w30
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