Mobil Mobil SHC 639
ISO VG 1000 extreme pressure gear oil
Buy
No retailer listing is on file for this oil. Email us and we will point you at a distributor. A quote form, and Zoro, Walmart, eBay, Grainger, MSC and Global Industrial, wait on programs that are not connected yet.
As an Amazon Associate, Evolvent Design earns from qualifying purchases. McMaster-Carr links are not affiliate links.
Key specs
| Spec | Value | Method |
|---|---|---|
| KV40 | 1000 cSt | ASTM D445 |
| KV100 | 98.8 cSt | ASTM D445 |
| Viscosity index | 184 | ASTM D2270 |
| Pour point | -42 °C | ASTM D97 |
| Flash point | 222 °C | ASTM D92 |
| Density at 15 °C | 0.87 g/cm³ | typical |
Grade checks
- KV40 is inside ISO VG 1000 (900–1100 cSt).
- Computed viscosity index is 191 from the stored KV40 and KV100 (ASTM D2270). The listed index is 184, more than 2 points away.
Viscosity and temperature
ASTM D341 (Walther) fitted to the published KV40 and KV100. It is an interpolation between those two points, and it is not meaningful below the pour point. Move the control to read a temperature.
Classification
- Category: Gear
- Attribute: Extreme Pressure
- Synthetic: Synthetic
- AGMA class: AS
- FZG fail stage: >=13
- Copper: 1B
- Note: Meets AGMA 9005-F16.
Sulfur, EP additives and yellow metal
Extreme-pressure gear oils use sulfur compounds so steel teeth do not weld under shock. That same sulfur can tarnish or pit copper, brass and bronze: a bronze worm wheel, a brass cage, a cooler tube. ASTM D130 sits a polished copper strip in the oil and scores the colour. 1A and 1B are the ratings to keep when yellow metal shares the oil. The strip below is that test at room temperature.
How lubricant-induced copper corrosion works
Equivalents
| Oil | Score | Why |
|---|---|---|
| Shell Omala S2 GX 1000 | 50 | same ISO 1000, VI 110 vs 184, additive ep, synthetic, AGMA AS |
| Chevron Meropa 1000 | 35 | same ISO 1000, VI 106 vs 184, additive ep, AGMA AS |
| Castrol Molub-Alloy GM 300s/1000 | 35 | same ISO 1000, VI 100 vs 184, additive ep, AGMA AS |
| Shell Omala S2 G 1000 | 35 | same ISO 1000, VI 85 vs 184, additive ep, AGMA AS |
| Castrol Optigear 1100/1000 | 35 | same ISO 1000, VI 83 vs 184, additive ep, AGMA AS |
Scores use published typical data. This is not an exact equivalent, and it is not an OEM approval. Confirm the substitute with the machine builder.
Documents
- Product data sheet
- Specs last read from the data sheet on 2026-09-09.
Related: Mobil, Mobil SHC 600, viscosity index calculator, ISO / SAE / AGMA chart.
Questions
Is Mobil Mobil SHC 639 an ISO VG 1000 oil?
Yes. The catalogue lists it as ISO VG 1000, which is a kinematic viscosity of 1000 cSt at 40 °C, plus or minus 10 percent (900 to 1100 cSt). Confirm the current data sheet before you fill a machine.
What is a Mobil Mobil SHC 639 equivalent?
No other brand in this catalogue clears the equivalents bar for this oil yet (same application, same grade, compatible base oil, and a score of 60 or more). That is not proof that nothing else works. Check the machine manual.
Can Mobil Mobil SHC 639 be mixed with another oil?
Mixing two oils that share a base family is sometimes done and sometimes a mistake. Do not mix this oil with a PAG. For any other mix, follow the maker's change-over guidance and the machine manual.
Report a data error
The report is stored for review. It does not change the page by itself, and it is not emailed anywhere yet.