On trail of wheel bearing failure

I have a 2004 Nissan X-Trail 4x2, which I enjoy driving, but I have had to replace the left front wheel bearing twice already, once at 65000km and now recently again at 90000km.

The vehicle doesn't go on farm roads, etc. In the latest incident I had to have the hub sleeved as it was badly worn. It seemed a bit odd that the second bearing packed up after only 25000km. But checking on the internet, worldwide everyone is complaining about the same problem. When I consulted Nissan SA, they claimed that they had never heard of such a problem. How strange.

Finding a bearing was a mission and a half in both instances.

My question is, why do Nissan not recall these vehicles? This is a design/quality control problem that they need to attend to. - David

I forwarded your letter to Nissan SA, and received a very speedy reply from Jacques Labotsky, senior manager: customer care. He reiterates that Nissan have not had any previous complaints in South Africa regarding premature wear of the bearings in question. He goes on to say: "Wheel bearings are considered friction items and are therefore considered wear and tear items. We kindly refer to Page W-5 of the Warranty Information and Maintenance booklet where it stipulates that Nissan should not be liable for costs of routine maintenance and service, replacement of consumable parts, glass, tyres or components subjected to normal wear and tear."

I find this statement rather puzzling as no mention was made of a warranty claim. I did ask Nissan to tell us what actually caused the failures on wheel bearings which their engineers have examined. They did not comply with this request.

The statement that wheel bearings are friction items and therefore wear and tear items, raises some disturbing questions. Friction is present in just about every rotating and reciprocating part of the engine and drivetrain. Are all these parts to be regarded as wear and tear items? I suppose Nissan would tell us that there is a difference between normal wear and tear and premature wear. But who decides where the dividing line is ?

In the case of the X-Trail's front wheel bearings, I spoke to an engineer at one of the biggest bearing manufacturers. Like almost all front wheel drive vehicles, the X-Trail uses sealed double row wheel bearings on the front hubs, not the tapered roller bearings commonly found on non-driven wheels. The sealed bearings are greased for life, have to be pressed out of the hub, and the new ones pressed back in.

Here's the hypothetical scenario that the bearing engineer sketched to explain David's experiences. I am not saying that this is exactly what happened in your case, David, but I am told it is sufficiently realistic to be of interest to many owners.

The initial failure at 65000km was probably due to impact damage, caused by striking a bad pothole at speed etc.

In such an event the rollers can make tiny indentations in the races, and, perhaps only some time later, the ominous "bearing rumble" appears. The state of our roads being what it is, 65000km is within the bounds of experience.

When the bearing was replaced the first time, either an inferior bearing was used, or, what happens more often, the installation wasn't done correctly. Removing and refitting sealed front wheel bearings is not a job for the amateur. It has to be done with a press, and, in addition, the operator has to know what he's doing.

Poor installation can easily lead to a bearing failure within 30000km. For this reason, owners are advised to stand by while new bearings are being pressed into a hub. A press is an expensive piece of equipment and a skilled operator should be a highly paid technician. If the workshop will not let you stand by, cancel the job card and drive away.

In view of these considerations, one has to conclude that Nissan have enough ammunition to reject a suggestion of a recall.