5w50 mobil 1- good or bad
- Thread starter red gt500
- Start date
Not the best, if you want to stick with 5w-50 look at redline or penzoil platinum.
If you are willing to run another viscosity, (it will shear down to the equivlant any way) look at amsoil.
I'll let Troy come in and explain all the technical stuff tomorrow
If you are willing to run another viscosity, (it will shear down to the equivlant any way) look at amsoil.
I'll let Troy come in and explain all the technical stuff tomorrow
:lol: True story stkjock, but I will help him on his way.
I have discovered that Mobil 1 5W-50 is 100% true synthetic, and does not contain and blended in refined petroleum. Six Speed has this as the current fill in his Shelby, and I am eagerly awaiting the UOA to see how well it performs. Please allow me to supply you with a few web links for better understanding of how 5W-50 lubricants are not the best choice for the Shelby. They are too viscous for street use, push the oil pump bypass open easily at low rpm, and it's even worse if you are using a cooler thermostat with lower fan settings.
Here are good links to start with. If you have any more questions, drop me a PM.
Oil thread #1
Oil thread #2
Oil thread #3
Oil thread #4
I have discovered that Mobil 1 5W-50 is 100% true synthetic, and does not contain and blended in refined petroleum. Six Speed has this as the current fill in his Shelby, and I am eagerly awaiting the UOA to see how well it performs. Please allow me to supply you with a few web links for better understanding of how 5W-50 lubricants are not the best choice for the Shelby. They are too viscous for street use, push the oil pump bypass open easily at low rpm, and it's even worse if you are using a cooler thermostat with lower fan settings.
Here are good links to start with. If you have any more questions, drop me a PM.
Oil thread #1
Oil thread #2
Oil thread #3
Oil thread #4
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Way to go Mobil 1. I knew there was something about how much I paid a quart that seperated it from the other oils. Now let the UOA show its ability to make things slide. Works good on bicycle chains too.
Your posts are amusing, and I enjoy your humor. Bicycle chains...lol
Mobil 1 regular syn 0W-20, 5W-20, 5W-30, 10W-30 all contain cheaper refined petroleum blended with true PAO synthetic base stocks. They are not 100% pure true synthetics.
Mobil 1 regular syn 0W-30, 0W-40, 5W-40, 5W-50, 15W-50 are all 100% PAO synthetic, as are all Mobil 1 EP formulations.
People are paying too much for Mobil 1 regular syn oils that contain refined petroleum in the formulation. It's overpriced. The same applies to Pennzoil Ultra and Platinum, and Castrol Syntec. You should be paying no greater than $5.00-$6.00 per quart. I'm thankful that buying it in gallon and 1.25 gallon bottles allow it to be priced more accurately, but that's still not saying much.
I only pay $30.00 per gallon of Amsoil 10W-30 or 10W-40 for the Shelby. You also can't find 5W-50 Motorcraft, Mobil, Pennzoil, or Castrol in gallon jugs to take advantage of this price reduction by volume in a common container.
Final thoughts....
It makes me laugh when Walmart shoppers grab a gallon of regular Mobil 1 5W-30 instead of 5W-30 EP. They would rather save $5.00 than buy the better lubricant. Oh well, not everyone is educated in this area of cars.
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and you could use it in your Shelby, as it would be superior to any 5W-50 you are using (assuming you are) due to oil pressure. Mobil 1 0W-40 is a great formulation. It even has higher ZDDP than API SN levels normally contain, so that's a plus.
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Thanks beast. I'll put amsoil 10W-40 next week. I'll try mobil 1 0W-40 next time i need oil...
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0W-40 Mobil 1 will also shear down to a 30 grade lubricant in short use, but will still be enough viscosity as long as you are not long session road racing.
Beast do you have a plot of oil pressure vs. RPM with the 10W40 yet? Would be good to see a comparison with 10W30, once you start using it in the Shelby.
It will be awhile before I'm ready to dump the M1 5W50 ... perhaps in the Winter. IMO M1 5W50 has a good additive pack with a bit more ZDDP (1000 ppm P and 1100 ppm Zn) than other API certified oils, and with a good dose of Boron and Moly for additional anti-wear/friction modifier protection. The virgin TBN is pretty high and it has ACEA A3/B3 and A3/B4 European oil certs for high performance cars, which must pass more stringent tests than oils meeting only API specs ... but we'll have to see what the UOA looks like. I fully expect it to shear to a 40 grade, but no more.
I am also considering a lower 40 grade oil too, but will wait until the power-train warranty expires next July. Thought M1 0W40 might be a good candidate, but I see it is a very light 40 grade and with a high viscosity index would be prone to shearing. Its virgin HTHS viscosity is 3.8 cSt, which barely exceeds the 3.7 cSt minimum required by the Ford B-spec for 5W50.
It will be awhile before I'm ready to dump the M1 5W50 ... perhaps in the Winter. IMO M1 5W50 has a good additive pack with a bit more ZDDP (1000 ppm P and 1100 ppm Zn) than other API certified oils, and with a good dose of Boron and Moly for additional anti-wear/friction modifier protection. The virgin TBN is pretty high and it has ACEA A3/B3 and A3/B4 European oil certs for high performance cars, which must pass more stringent tests than oils meeting only API specs ... but we'll have to see what the UOA looks like. I fully expect it to shear to a 40 grade, but no more.
I am also considering a lower 40 grade oil too, but will wait until the power-train warranty expires next July. Thought M1 0W40 might be a good candidate, but I see it is a very light 40 grade and with a high viscosity index would be prone to shearing. Its virgin HTHS viscosity is 3.8 cSt, which barely exceeds the 3.7 cSt minimum required by the Ford B-spec for 5W50.
Yeah I try. Waiting to send the oil analysis in for the car. Just changed it at 2,500 miles and took forever to get that. Just grabbed some more Syntec since it is so readily available. However if the analysis doesn't look stellar will change it immediately. Hardily ever drive the car lately.
Those temps with a stock thermostat and cooling system?
Definitely go with Amsoil 10W-40. Your going to need it.
So far, it cold starts at 50-55 PSI, hot idle at 25-27 PSI, and cruise at ~50 PSI. The oil pressure is much improved, and doesn't open the oil pump bypass nearly as easy.
I agree, since it isn't a standard passenger car grade, and has to pass tougher specs. If it does shear to a heavy 30 grade, I suspect it would take many more miles than 2,000 like Motorcraft. More like 5,000+ (guessing)
Motorcraft 5W-50 is not 3.7 HT/HS when it shears to a heavy 30 grade. It's more like 2.9 at best. Ford even says MC 5W-50 is good for what...7,500 miles on the normal interval?
Your thoughts?
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170 thermostat and c&r HE ..
but i am talking about the hot weather we have not the (iat2...).
thanks..
Kinematic viscosity (KV) of the Motorcraft shears about 30% over 4000 to 6000 miles. I've seen data that suggests HTHS of oil shears about half as much percentage wise as its KV shears ... so about 15%. Assuming MC starts out with a HTHS of 3.7 cP means it will shear to 3.1 cP after 4 to 6K miles and even more after 7500 miles. I'm thinking the virgin MC 5W50 HTHS is slightly higher than 3.7 cP, but not by much. CP probably had to bump up the KV to the spec value of 21 cSt (nearly a 60 grade oil) in order to achieve the required 3.7 cP minimum HTHS ... just speculating.
Are these numbers are for the 30 grade oil or 40 grade? I'm assuming cruise is between 1700 to 2200 rpm.
I'm also running a 170* thermostat, and my car runs great off 10W-30. The oil pressures are great.
The pressures experienced above are with Amsoil 10W-30, and cruising speeds are exactly where you stated.
10W-40 looked more like this. 75 PSI cold start, 30 PSI hot idle, ~70 PSI cruising, blowing past the oil pressure bypass valve by 3,000-3,500 rpm at WOT (maxed out at ~85 PSI).
Michael @ L&M Engines was breaking in a new GT500 engine with conventional 10W-30. He reported oil pressures that were too high for normal operation (80 PSI @ 2,500 rpm). This was a built engine of course, and not stock.
All of the MC 5W-50 UOAs I have range from 30%-40% shearing (samples ranging from 2,000-4,900 miles), so let's take the average at 35%. 1/2 = 17.5%
Let's assume MC 5W-50 has a HT/HS of 3.8 (slightly more than the spec'd 3.7).
3.8 - .665 (17.5%) = 3.135 HT/HS
Amsoil 10W-30 is spec'd for HT/HS of 3.2, and we know it will not shear at all. That should make it safe to use under normal street driving conditions, and short bursts of competition driving. This is also assuming a cooler thermostat is being used increasing the safety barrier.
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