gt 500 oil?
- Thread starter 10gt5
- Start date
We have beat this topic to death, but I think you will find in the thread link posted below.....Amsoil is doing an awesome job.
GT500 UOA thread
GT500 UOA thread
Have you ever thought of looking on the oil cap or even the owner's manual for weight reccomendation?
My next statement will address both of these posts.
Amsoil will not openly/publicly recommend a lubricant that isn't specifically formulated to meet the viscosity requirements set forth by the manufacturer. Is this because that's the best lubricant to use, not at all. It's due to legal implications. Amsoil's in house legal department will not allow them to.
Amsoil has no desire to produce a 5W-50 for two reasons.
- It's only recommended for a few models, low production cars, not used by other manufacturers (i.e. Ford specific)
- The formulation is weak, and not what you believe it is
Motorcraft 5W-50 is actually a 20W-50 above 32*F until it shears. SAE numbers on the outside of a lubricant bottle are very misleading.
The formulation rapidly shears to a light 40 grade lubricant in as little as 1,500-2,000 miles.
I always recommend a true synthetic 10W-40 like Amsoil AMO for stock thermostat cars. It will not shear like motorcraft, has better cold flow properties, and a more robust additive package. It also offers 50% lower evaporation/burn off.
If you call Royal Purple, they will tell you to use their HPS 10W-40.
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If warranty compliance is still important use an API-SN 5w-50 synthetic, because that is all Ford will recognize as compliant.
If you can find the above oil in anything other than a Motorcraft oil, good luck to you.
Once warranty is not an issue, let there be no doubt there are better options than the 5w50 Motorcraft.
We do not think a 50 weight oil of any type is needed to provide appropriate protection in these primarily street driven supercharged engines with the tight internal tolerances they have. Instead use a high film strength performance oil.
Your best choice is Royal Purple XPR 10W-40(part #01041, quarts bottle).
Next best choice which also has the highest bang for the buck factor...is...
Royal Purple HPS 10w40 (part# 31140, quart bottle)
If you can find the above oil in anything other than a Motorcraft oil, good luck to you.
Once warranty is not an issue, let there be no doubt there are better options than the 5w50 Motorcraft.
We do not think a 50 weight oil of any type is needed to provide appropriate protection in these primarily street driven supercharged engines with the tight internal tolerances they have. Instead use a high film strength performance oil.
Your best choice is Royal Purple XPR 10W-40(part #01041, quarts bottle).
Next best choice which also has the highest bang for the buck factor...is...
Royal Purple HPS 10w40 (part# 31140, quart bottle)
Why Royal Purple and not Amsoil?
Using Royal Purple HPS, XPR, or Amsoil will give you far greater results than Motorcraft 5W-50.
Using either is a better choice than Motorcraft.
I choose Amsoil because I can buy it 25% off retail. Everyone can do that.
Cool....I went and ordered the amsoil...had it in the GT500, so figured I'd do the same in the new Boss. Thik it will be good to change once I hit 1000 miles?
Your rings will be seated before then, so it's fine. I've never let a new performance car go beyond 1,500 miles before changing the factory fill.
No, it's actually less viscous, but that's a good thing.
Ford scared everyone into thinking the engine would die if you did not use a 50 grade lubricant. That is BS to say the least. Ford spec'd 5W-50 because it was a viscous lubricant for the short term and would shear rapidly. They want it to shear, as a 50 grade lubricant in this engine is too much.
Absolutely, Motorcraft 5W-50 is inferior to say the least.
Steve,
No comparison in quality of formulation. AMO (100% true synthetic, very robust additive package) > XLO (Hydrocracked & true synthetic blend)
I can get you, or anyone, Amsoil AMO 10W-40 at cost. $7.75 per quart....$30.35 per gallon....$88.50 per case.
cool. thanks man. i just signed up for their 6 month trial thingy. going to order 2 oil changes worth of the stuff :beer:
Guess at my first oil change at 1000 miles, I will switch over to Amsoil 10w40. I was worried about it voiding warranties and such.
Wouldn't worry about that, AMO looks so much better on a UOA (used oil analysis) that Ford could never call shenanigans.
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