While working on an old 110 chassis I removed the hubcaps and beauty rings and came across something very puzzling on the right front wheel. As you can see in the picture it is just covered in grease. At first I could not figure out how that could have happened. After further diagnosis the cause became obvious. Hard to believe it is related to the brake caliper.
Problem & Solution
Common among these chassis:
I ran a little contest on this website. A number of customers wrote in with an answer. Only two had the single correct answer. Some guessed a loose cap, lack of grease, or wheel bearing too tight. Although these can be a problematic, none of them would create the EXTREME heat required to melt the wheel bearing grease to the point where it could leak through the grease cap and spin all the way out and onto the tire! This condition was caused by a seized brake caliper allowing the brake pads to drag against the rotor. This is a SERIOUS condition and can cause the grease to boil. I have seen the front grease on a Mercedes catch on fire due to dragging brakes.
MORAL OF THE STORY:
- If you see grease like this forming on a wheel, stop driving the car and inspect the brakes immediately.
- If you purchase an old Mercedes DO NOT drive it home (unless you have it thoroughly inspected it first). If you are purchasing remotely have it trailered to your location. It is just not worth the risk of breaking down in Timbucktoo... Even if the brakes on this car had been inspected and were passed, there were still numerous problems with crack fuel hoses and an empty power steering pump due to a leaking hose. An engine fire can even be worse than a brake fire!
- ALWAYS flush the brake system with fluid every two years. Old brake fluid absorbing moisture is the leading cause of frozen brake calipers.