So do the syn oils such as Mobile 1 meet or exceed EVERY spec in Motorcraft 5w20? I mean EVERY statistic that Ford could come up with?
5W20 oil: The Hard Truth
- Thread starter ChicagoMike
- Start date
Can anyone say definitively that the '03 and '04 Oil Passage Design was changed to only work with 5w-20?
That has to be the most important question besides the warranty issue. I would like to stop quessing and get an answer to this question; surely this can be answered by someone with factual knowledge.
Discussing which oil is best is pointless if we cant even find out for sure whether the car is even supposed to take above 5w-20 oil.
That has to be the most important question besides the warranty issue. I would like to stop quessing and get an answer to this question; surely this can be answered by someone with factual knowledge.
Discussing which oil is best is pointless if we cant even find out for sure whether the car is even supposed to take above 5w-20 oil.
thor on modularfords.com can tell you that the answer is a definitive NO
Can u clarify the No u gave?
No the Cobra isnt built for just 5w-20?
No to any other weight?
No the Oil Passage Design is not to small for 30, 40 weights?
No the Cobra isnt built for just 5w-20?
No to any other weight?
No the Oil Passage Design is not to small for 30, 40 weights?
Yes please clarify what you are saying no to, the modification to the engine passages? and who exactly is Thor?
Can't one of the Ford Engineers tell us?
Can't one of the Ford Engineers tell us?
I checked out those forums and Thor only has 14 posts. Not sure I want to really take his word for it.
The passages that were changed to the later 03 heads were coolant flow around #7 and #8 ...the exhaust valves would get too hot( not enough heat pulled out by the coolant though the guide area)...resulting in the "tick"From what I've read both "thor" and cobra'03 are extremely credible...In my humble opinion
Btw when I do get mine I will be doing the "race engine builders lean on it hard and change often w/ dino oil method"
after that...aboust 10k or 15k a premium 5w30 synth....WHY???
because no one is going to freaking know!
I work at a Linc/Merc dealer and the only time anyone starts asking questions on a blown motor.....Is when the oil hasn't been changed(sludge) or there isn't any oil.
Seriously take the time to read cobra'03's thread it is excellent!:thumbsup:
Btw when I do get mine I will be doing the "race engine builders lean on it hard and change often w/ dino oil method"
after that...aboust 10k or 15k a premium 5w30 synth....WHY???
because no one is going to freaking know!
I work at a Linc/Merc dealer and the only time anyone starts asking questions on a blown motor.....Is when the oil hasn't been changed(sludge) or there isn't any oil.
Seriously take the time to read cobra'03's thread it is excellent!:thumbsup:
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on my built longblock jdm reccomended 5w20 motorcraft.
Wrong. Same block, same crank, slightly different heads (flow more, but essentially the same head).
Good post, Jimmysidecarr, cobra'03 is pretty much the lubrication expert around here, saying the same things I'm getting from a Ford Engineer.
One side note, soontobecobra, you're really worried about messing up your warranty, you can use the 20W oil and have no problems getting the warranty, but if you drive the car to potential, there's a better chance you'll have an oil related (warrentied, of course) than if you went with a 30W oil (less likely to have oil related problems, probably warrantied as well)
One thing, if you plan to mod the car (I'm seeing that you don't plan to) it would be better is you DID switch to 30W oil.
If you're more worried about the warranty than the longevity of your motor (after doing a bit of reading on 20W motor oils, tons of stuff out there, not all of it from here) then you'd be best served using exactly what Ford specifies.
Yes, it's another opinion, but you can research it, looking for other (probably better) sources. Bear in mind that every guy that has one of these cars has gone through the same thing you're going through.
I did. For my area, Amsoil 10w30 is best, (anyone's 10w-30, not selling Amsoil)
The 30w oil will support the motor's bottom end better. I got that from a Ford engineer, on another board, he suggested 10w-30, cobra'03 suggests 0w30 for his area.
If you're not willing to look at the advice of several local lubrication heavyweights, cobra'03 being one of them, all you're likely to get is more opinions (like this one) and a satisfactory answer is unlikely to appear on this board.
Good luck, you're joining a good crowd.
One side note, soontobecobra, you're really worried about messing up your warranty, you can use the 20W oil and have no problems getting the warranty, but if you drive the car to potential, there's a better chance you'll have an oil related (warrentied, of course) than if you went with a 30W oil (less likely to have oil related problems, probably warrantied as well)
One thing, if you plan to mod the car (I'm seeing that you don't plan to) it would be better is you DID switch to 30W oil.
If you're more worried about the warranty than the longevity of your motor (after doing a bit of reading on 20W motor oils, tons of stuff out there, not all of it from here) then you'd be best served using exactly what Ford specifies.
Yes, it's another opinion, but you can research it, looking for other (probably better) sources. Bear in mind that every guy that has one of these cars has gone through the same thing you're going through.
I did. For my area, Amsoil 10w30 is best, (anyone's 10w-30, not selling Amsoil)
The 30w oil will support the motor's bottom end better. I got that from a Ford engineer, on another board, he suggested 10w-30, cobra'03 suggests 0w30 for his area.
If you're not willing to look at the advice of several local lubrication heavyweights, cobra'03 being one of them, all you're likely to get is more opinions (like this one) and a satisfactory answer is unlikely to appear on this board.
Good luck, you're joining a good crowd.
Here's the thread, my info from the Ford engineer came from the NVMC board, and has been deleted from there (so don't look) Luckily I cross posted it on this board.
http://www.svtperformance.com/forums/showthread.php?s=&threadid=69539
The engineer is Roger Burnett, and he's gracious enough to answer direct questions for almost any applications.
You'll have to register (free) and go on and post your query. He will respond.
http://www.northernvirginiamustangclub.com/
Try not to swamp him!!
http://www.svtperformance.com/forums/showthread.php?s=&threadid=69539
The engineer is Roger Burnett, and he's gracious enough to answer direct questions for almost any applications.
You'll have to register (free) and go on and post your query. He will respond.
http://www.northernvirginiamustangclub.com/
Try not to swamp him!!
0/20
I use 0/20 syn adds major life to engine, horsepowergains and milage
I use 0/20 syn adds major life to engine, horsepowergains and milage
guys, this has all been hased out before. read cobra'03's posts
Hey again, thanks guys for cobra03's link. I did do a search and read for hours before I kept seeing the same talk. I didn't get past this or another similar thread before I got to cobra03's february 2002 thread.
I am fully satisfied that I can use my preferred choice of 10W-30 Amsoil. I live in New Orleans so I dont anticipate ma problem at all with very cold whether.
Lastly, I care much more about car longevity, but I also dont want to lose the warranty so I was just a bit concerned about how to reconcile the two.
As far as mods, I intend on doing just the cat-back or aft-cat change just to get nicer sound. I am never going to race it or push it limits at all so I wouldnt worry much about a blown engine.
I am fully satisfied that I can use my preferred choice of 10W-30 Amsoil. I live in New Orleans so I dont anticipate ma problem at all with very cold whether.
Lastly, I care much more about car longevity, but I also dont want to lose the warranty so I was just a bit concerned about how to reconcile the two.
As far as mods, I intend on doing just the cat-back or aft-cat change just to get nicer sound. I am never going to race it or push it limits at all so I wouldnt worry much about a blown engine.
Aren't you guys both from the same area?
They want a definitive answer. Don't think there really is one.
I called SVT a month ago regarding this issue, they referred me to calling the dealership, there, they told me to stick with 5W20 as well, however; after reading this information and doing the research myself, I will be switching to Amsoil 5w30. Anybody know if running 3 different oils through a motor before settling on a brand is bad ju ju?
I'm with cobra'03 on this. Here's my experience so far. Had my first and only oil change so far done by the Ford dealer. Here were my choices:
5W30 conventional
5W30 syn-blend
5W30 synthetic
I asked about the 5W20; service rep said they don't use it & you don't need it. So here's the dealer putting 5W30 into every 03 car that comes in for a change. You think he's going out on a limb risking warranty work on all these cars? I doubt it.
Just for peace of mind I called SVT & got the same answer as many others have: 5W20 was spec'd for fuel economy only; 5W30 is OK to use and wait for 5-6k miles before going to full synthetic.
5W30 conventional
5W30 syn-blend
5W30 synthetic
I asked about the 5W20; service rep said they don't use it & you don't need it. So here's the dealer putting 5W30 into every 03 car that comes in for a change. You think he's going out on a limb risking warranty work on all these cars? I doubt it.
Just for peace of mind I called SVT & got the same answer as many others have: 5W20 was spec'd for fuel economy only; 5W30 is OK to use and wait for 5-6k miles before going to full synthetic.
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Blackmagic94
Banned
If you are worried about it then buy Royal Purple 5w20 full syn. All 5w oils are the same thickness, its just a 5w-20 provides the equivent of a 20w oil when warm not that it actually gets thicker with heat. And the only syn 5w20 is Royal Purple that i know of and the Motorcraft is the only blend, all others from Castrol or Penzzoil are dino oil,
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