That is really confusing, if I search on their site (
https://www.fcsdchemicalsandlubricants.com/main/searchdiesel.asp) for Diesel Motor Oils Meeting
WSS-M2C171-F1 I get:
Brand Name Viscosity
711 SynShield™ OTR Plus SAE 10w30 10W30
722 SynShield™ Ultra Performance SAE 10w30 10W30
Advantage HD DEO Synthetic Blend 10W30
Advantage Ultra Premium Plus 10w30 CK-4 10W30
Advantage Ultra Premium Plus 10w30 CK-4 10W30
All Fleet T SAE 10w30 10W30
All-Fleet Plus 10W30
All-Fleet Plus E900 10W30
Allied 10W30
Altra Fleet 10w30 CK-4 10W30
Bestbuy Diesel 10W30
Big Red 10W30
Blue Mountain Professional 10W30
CAM2 SYNTHETIC BLEND SUPER HD 10W30
Capital Bulk 10W30
CARQUEST 10W30
Carquest Premium Diesel 10W30
Chemlube Premium Multi-Fleet 10W30 CK4 Engine Oil 10W30
CITGARD® 700 Synthetic Blend Engine Oil 10W30
D-MO SAE 10w30 10W30
Doosan 10W30
Duragard 10W30
Duralect 10W30
Duralene Dura-Max SB 10w30 CK-4 10W30
Duron SHP 10w30 10W30
Dyna-Plex 21C SHPD 10W30
Eco Ultra Premium Diesel 10W30
EcoPower 10W30
ECOSE Horizon HD 10W30
ECOSE Horizon Synthetic Blend 10W30
Federal Maxxum LE Synthetic Blend 10w30 CK-4 10W30
Five Point 10W30
Fleet Pro Elite Synthetic Blend 10W30
Fleetrite Synthetic Blend 10W30
FS Suprex 10W30
Gibraltar Super S-3 LX 10w30 CK-4 10W30
Golden West 10W30
Gulf Super Duty Plus 10W30
Gulf Super Duty Plus SB 10W30
Harvest King 10W30
HyFilm LEO 10w30 10W30
Hyperion Blend 10W30
IDO Premium Plus 10W30
Kendall SUPER-D XA® w/ Liquid Titanium® 10w30 10W30
Kendall SUPER-D® EC 10w30 10W30
Klondike 10W30
Klondike Synthetic Blend 10W30
Lube King 10W30
LubeForce 10W30
Lubriguard 10W30
Mag 1 10W30
Mag 1 Synthetic Blend 10W30
Mahindra 10W30
Maxtron DEO 10W30
MFA OIL 10W30
Mobil HDEO 10W30
Monarch Diesel Ultra Semi-Syn 10w30 CK-4 10W30
Monarch Diesel Ultra Syn 10w30 CK-4 10W30
Monolec® Ultra Engine Oil 10W30
Motorcraft Super Duty Diesel Motor Oil 10W30
Mystik® JT-8® Synthetic Blend Super Heavy Duty Engine Oil 10W30
Napa Value 10W30
Navi-Guard Extreme Synthetic Blend CK-4 10w30 10W30
Navi-Guard Premium Fleet Plus CK-4 10w30 10W30
Oilzum Special CK-4 10w30 10W30
Parts Master 10W30
PEAK Heavy Duty 10w30 10W30
PEAK Heavy Duty Synthetic Blend 10w30 10W30
Performance Plus 10W30
Phillips 66 FLEET SUPREME EC® 10w30 10W30
Phillips 66 GUARDOL ECT® w/Liquid Titanium® 10w30 10W30
Pro Guard Premium 10W30
ProSpec V Synthetic Blend 10w30 10W30
Purezone Premium Diesel 10W30
PURUS Synthetic Blend 10w30 10W30
Reliant 10w30 10W30
Rotella T4 Triple Protection 10W30
Royal Purple Duralec Super 10w30 10W30
Sinclair 10W30
Sonic D-MO SAE 10w30 10W30
Sunoco Super C Gold 10w30 CK-4 10W30
SUPER S FG-2000 SYNTHETIC BLEND 10W30
Superline™ 10w30 10W30
Superlube TMS 10W30
THRIVE HEAVY DUTY DIESEL CK-4 10w30 10W30
Titan SAE 10w30 10W30
TOTAL Rubia Optima 1100 FE 10W30
TOTAL Rubia Optima 1100 FE 10W30
Tune-It 10W30
Ultra Fleet HD Synthetic 10w30 10W30
United Super Diesel 10W30
United Super Premium Fleet 10W30
Universal Dezol 10W30
Wakefield Diesel Engine Oil 10w30 CK-4 10W30
Williams Titan 800 Synthetic Blend 10w30 CK-4 10W30
Xtreme Fleet 10W30 CK-4 10W30
So they have a blanket statement that
NO 10w30 meets their spec, but then give you this huge list of ones that are approved? I'd not want to own a brand new one of their pickups right now, I feel like there is no way to weave through this without "getting it wrong" somewhere.