ISO VG 320

ISO VG 320 collects 53 oils from Castrol, Chevron, Mobil, Shell in this catalogue. The ISO viscosity grade is the oil's thickness at 40 °C, plus or minus 10 percent. Match the grade the machine manual names before you compare brands. The figures below are the makers' typical values, not a batch certificate. Confirm the current data sheet before you fill a machine. Published viscosity indexes run from 92 to 240. A higher index thins less between 40 °C and 100 °C. That matters in a cold start and in a hot gearbox, and it is not the same thing as the ISO grade. Pour points run from -48 °C to -6 °C. The machine should still start at least 5 °C warmer than the pour point of the oil you pick. 23 are flagged synthetic and 30 are not. Synthetic here means the maker said so. It is not a viscosity grade and it is not, by itself, a reason to leave the ISO grade the manual asks for. 4 of these oils are PAG (polyalkylene glycol). PAG does not mix with mineral oil or PAO. Drain and flush before a change into or out of a PAG, and do not treat a PAG as an equivalent of either. 8 can be bought in a small package from the retailers linked on each oil page. The others have no listing yet. A missing buy button is not a comment on the oil. Use the table to sort the grade, the viscosity index and the pour point, then open an oil for its data sheet, its equivalents and its buy links. Equivalents on this site are other published oils in the same application and grade. They are not exact substitutes, and the OEM specification still governs.

Oil	ISO	KV40	VI	Pour	Buy
Mobil Glygoyle 320	320	320	240	-33	—
Castrol Optigear Synthetic 800/320	320	320	230	-30	—
Shell Omala S4 WE 320	320	321	230	-39	—
Shell Omala S3 A 320	320	319	200	-21	—
Mobil Mobil SHC Gear 320	320	320	181	-48	—
Castrol Optigear Synthetic X/320	320	325	179	-45	—
Mobil Mobil SHC Gear OH 320	320	320	178	-45	Yes
Castrol Optigear Synthetic PD 320 ES	320	330	177	-45	—
Castrol Optigear Synthetic CT	320	335	174	-45	—
Mobil Mobil SHC 632	320	320	172	-48	Yes
Shell Omala S5 Wind 320	320	320	170	-48	—
Shell Omala S4 GXV 320	320	320	169	-42	Yes
Shell Morlina S4 B 320	320	320	168	-42	—
Chevron Meropa Synthetic EP 320	320	304	165	-39	Yes
Chevron Tegra Synthetic Gear 320	320	304	165	-39	—
Mobil Mobilgear SHC XMP 320	320	335	164	-38	Yes
Chevron Clarity Synthetic Machine Oil 320	320	304	162	-42	—
Chevron Meropa EliteSyn XM 320	320	320	160	-36	—
Shell Omala S4 GX 320	320	335	159	-42	—
Chevron Meropa Synthetic WM 320	320	320	156	-48	—
Chevron Meropa EliteSyn WL 320	320	320	152	-45	—
Chevron Cetus Hipersyn 320	320	336	142	-34	—
Castrol Optigear Synthetic A/320	320	330	140	-36	—
Castrol Optigear Synthetic 1710/320	320	320	138	-30	—
Chevron Meropa XL 320	320	320	124	-30	—
Castrol Molub-Alloy GM 690/320	320	320	102	-15	—
Castrol Optigear BM 320	320	320	100	-15	—
Shell Omala F 320	320	320	100	-18	—
Shell Omala F Wind Oil 320	320	320	100	-18	—
Shell Omala S2 G 320	320	320	100	-15	—
Chevron Clarity Machine Oil 320	320	304	98	-12	—
Chevron Meropa 320	320	320	98	-22	Yes
Shell Omala S2 GX 320	320	320	98	-15	—
Chevron Aries 320	320	320	97	-18	—
Chevron Rando HD 320	320	301.8	97	-12	—
Mobil PM Ashless 320	320	320	97	—	—
Mobil 600 XP 320	320	320	97	-24	Yes
Mobil EP 320	320	320	97	-24	—
Mobil Vacuoline 537	320	309	96	-12	—
Shell Morlina S2 B 320	320	320	96	-12	—
Castrol Optigear 1100/320	320	317	95	-21	—
Castrol Optigear EP 320	320	326	95	-9	—
Chevron Regal R&O 320	320	304	95	-12	Yes
Mobil PM 320	320	320	95	-6	—
Mobil Teresstic 320	320	320	95	-12	—
Mobil Vacuoline 137	320	320	95	-9	—
Shell Morlina S1 B 320	320	320	95	-6	—
Shell Morlina S3 BA 320	320	320	95	-6	—
Shell Paper Machine S2 M 320	320	320	95	-9	—
Shell Paper Machine S3 M 320	320	320	95	-21	—
Castrol Optigear ALR 320	320	320	95	-9	—
Chevron Paper Machine Oil Premium 320	320	304	92	-12	—
Shell Air Tool Oil S2 A 320	320	320	—	-18	—