5C calls for 30w, what are you guys using? Thinking 15w 40? Thanks
Most owners use the Lucas hub oil cost 10 or 12 bucks a Qt.me personally I wouldn't use the 15 -40 engine oil
Yep what Clifford said. :^
I also use the Lucas hub oil. I've removed the hubs and checked the bearings after about 5000 miles and they are in great shape. I know 5000 miles is not a lot, but I also frequently check the temperatures of the hubs when we stop and no excess heat.
Thanks to all. I just ordered 4 quarts Lucas oil from Amazon $40 to my door.
Good move >>>Dan
Would 85W-140 GL-5 hypoid gear oil also work OK in front hubs? I don't know what's in mine, but I suspect it's GL-5 there now.
John
I want to change the front wheel bearing oil on an MC8. The manual states the front and trailing hubs should use engine oil? The drives use SAE140 of running above 0F.
Following is the spec for Lucas hub oil. It says 65-85 but later the comments state it is more like 90-140 so in the range for both drives, front, and trailing hubs.
4 quarts in the Amazon cart!
Lucas Hub Oil is a heavy-duty lubricant designed specifically for steering axles and trailer hubs. It is widely used as a preventative maintenance product because it can recondition seals to stop leaks and allow hubs to operate even if oil levels become marginal.
+1
Below are the technical specifications and typical properties based on the manufacturer's data sheet:
Technical Specifications| Property | Typical Value | ASTM Test |
| Viscosity @ 100°C | 65.0 – 85.0 cSt | D-445 |
| API Gravity | 23.6 | D-1298 / D-4052 |
| Specific Gravity @ 60°F | 0.9123 | D-1298 / D-4052 |
| Density @ 60°F | 7.597 lbs/gal | D-1298 / D-4052 |
| Flash Point (COC) | 430°F (221°C) | D-92 |
| Color | Amber | Visual |
| Odor | Characteristic Petroleum | — |
Export to Sheets
Key Features & Performance
- Leak Prevention: Formulated to "dry up" and stop most seal leaks in heavy-duty truck steering axles and trailer hubs.
- Viscosity Rating: While often categorized generally as a hub lubricant, some technical listings relate its thickness to an SAE 250 or a very heavy SAE 90/140 equivalent, depending on the specific application needs.
- Compatibility: It is a conventional (petroleum-based) oil but is generally compatible with other synthetic and conventional gear oils (like 75W-90 or 80W-90) if used as a top-off.
- Extreme Pressure: Designed to maintain a "tenacious" lubricant film that reduces friction and helps hubs run cooler under heavy loads.
Common Part NumbersNote: This product is intended for hub cavities. While it is an excellent gear lubricant, always ensure it meets your specific OEM requirements for gearboxes or differentials if using it outside of wheel hubs.
Materials used in the bearings and seals has changed a lot from a manual written 50 years ago. There are several different hub oils on the market Lucas is the most popular because it is sold everywhere and easy to find. I have a trailer that specs Morley's hub oil and I have never seen it except at the ABF truck shop here so I use Lucas