Problem:  Oily smell, greasy wheel hub and rim

Solution Difficulty:  Difficult

It had been a while since I'd had any trouble out of my Passat. Then a few months went by and I began to notice a distinct oily smell from the car. I would only catch a whiff of it every now and then so I figured it wasn't a serious oil leak. Just incase I kept and eye on the level of engine oil so I could avoid any serious damage.

The oily smell continued for a while and then one day when I had the car in the shop to change the oil I made a discovery. While checking the brake pad thickness on my driver's side I noticed that the inside of the wheel hub was incredibly dirty. In fact it was all greasy, more so than if I'd just splashed some gunk up from the road. So I removed the tire and took a look around. To my surprise I found wads of grease everywhere. On the wheel well, on the spindle and all over the brake caliper.

Further inspection revealed that the rubber boot around the CV joint had broken loose and the grease inside had been flying out. Evidently the grease would be thrown on to the brake caliper which would heat up after a while and cause the oily smell.

I was happy that I'd figure out the problem, but now I was pretty concerned about the health of the CV joint. Since this had been going on for a while I figured that the inside of the joint had long been contaminated with dirt and grit so the joint would eventually fail. I didn't want that to happen while I was driving down the road so I immediately hit Auto Zone to order a replacement.

A week later I replaced the entire CV axle, as the joint is permanently attached to an axle or half-shaft depending on how your engine is set up. Unfortunately, the newly re-manufactured CV axle later had a problem, and a few months later I discovered it. The rubber boot was fine but for some reason the metal clip that clamps down the boot had broken free. Again the grease was slinging out as I drove, although not nearly as bad as the first time.

I joked about the problem saying that after several thousand miles of slinging grease, at least all the metal parts were well lubricated against corrosion. At the very least I gained a lot of experience changing out CV axles. Before I made the second change-out I inspected the passenger side CV joint and found a small crack beginning to form. Dead set on preventing another grease-out I ordered a replacement for that side as well.

The primary thing you need to do in order to change the CV joint is to raise the vehicle. The more clearance you can get the better. Second, be very careful about inserting the splined end of the CV axle into the wheel hub. I managed to wreck the wheel speed sensor on the driver side wheel when I forced the replacement part into place.

The opposite end of the CV axle is a piece of cake, and in this case was held into place by five torx headed bolts. The real challenge is to get everything into place which will require you to either flex the CV joint or turn the steering wheel or possibly both.

After making this change I can honestly say that I have a real respect for the WRC mechanics who frequently change out joints and drive shafts under cars that are only suspended by a set of metal ramps. It's really hard to maneuver a huge piece of steel with a bulky bit on either end, especially when your flat on your back. It's not impossible but it can be a bit like a Tetris puzzle at times.

This article contributed by ERSWeb
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