Oil brand and Viscosity

[jpl5007]

From what I've read the 5w50 is for vehicles being driven really hard all the time therefore it may be too thick for street use, and comes with some potential problems:

The Motorcraft 5W50 shears very quickly to a 40 grade; my 1350 mile UOA showed KV @ 100 degrees was down from a VOA value of 19.93 cSt to 15.06 cSt. The oil was from a 07 GT500 driven fairly conservatively.

Motorcraft and Castrol 5W-50 lubricants quickly shear to a light 40 grade after only 2,000 miles. I've seen two samples that were already at the heavy 30 grade viscosity after only 2,000 miles. I also haven't seen many UOAs from the GT500s using Motorcraft or Castrol 5W-50 that looked as good as my GT500 using Amsoil 20W-50.

My current fill is Amsoil 10W-40, and a UOA is just around the corner. I suspect this will be the winning lubricant for this engine, and also why Royal Purple suggests this grade exclusively.

Amsoil 20W-50, Amsoil 10W-40, and Red Line 5W-50 are true synthetic base stocks. No refined petroleum is present in the formulation. It's high in ZDDP (major anti-wear additive). Motorcraft and Castrol 5W-50 use a highly refined petroleum base stock. Lower in ZDDP

 

[STIG302]

I always use the manufacturer's recommended viscosity so there's no chance of voiding the warranty. What's your source for the quotes?

 

[roywilk1960]

0-40 Mobil 1

 

[jpl5007]

The Motorcraft 5W50 shears very quickly to a 40 grade; my 1350 mile UOA showed KV @ 100 degrees was down from a VOA value of 19.93 cSt to 15.06 cSt. The oil was from a 07 GT500 driven fairly conservatively.

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2186995

Amsoil 20W-50, Amsoil 10W-40, and Red Line 5W-50 are true synthetic base stocks. No refined petroleum is present in the formulation. It's high in ZDDP (major anti-wear additive). Motorcraft and Castrol 5W-50 use a highly refined petroleum base stock. Lower in ZDDP

http://www.svtperformance.com/forums/shelby-gt500-150/756306-whats-best-oil-your-shelby-answers-within.html

 

[AZBoss302]

0-40 Mobil 1

+1 This is what I'm planning on using also. If someone has the part number for the oil filter handy, please pass on........

 

[2012YellowBoss]

If you are asking about the Ford filter it is FL500S but the FL820S will work, it is larger so it holds more oil and has a bigger area for cooling but not by much. You will have to be careful using it with your warranty since it not the part called for.

 

[JScheier]

0w30 Castrol Syntec.... affectionately referred to as German Spec or GC on Bob is the Oil Guy. Ran it for 8 years in the M3 with stellar Blackstone reports. Seems to take track abuse very well.

 

[jimprw]

For now I'm sticking to Motorcraft 5W-50. It doesn't cost more than the current alternatives as far as I can tell and makes life simple. The weather here in MN doesn't get overly hot for any extended period of time and I won't be driving it during the winter months.

 

[BossJockey]

I was going to run Mobile 1 0W-30 but I found Royal Purple 5w-30 for less so I went with that.

 

[stuntman]

5W50 Motocraft
0W40 Mobil 1
5W40 Shell Rotella "T6"