Rear Wheel Bearing Problems VW Passat '94

Hello everyone!

'I'm having major problems with the rear wheel bearings on my Passat TDI, manufactured in 1994. They seem to fail after about 20,000 to 30,000 kilometers. The inner bearing then becomes completely rusted. The remaining grease turns brown. The outer cover was sealed with silicone, so water shouldn't be able to penetrate from there, and the outer bearing is much less affected. If the vehicle is parked after a drive in wet weather with the handbrake engaged, the handbrake will be seized solid the next day due to rust. The brake pads are also heavily rusted. So, it must be that water is getting in somewhere significantly. Has anyone else observed something like this?'

Best regards, Ide.

Hi Ide.

Hey, where are you parking? In the swimming pool?

Just kidding:
That much moisture cannot penetrate to the axle shaft if the seal is intact, causing the wheel bearing to rust. I assume that a generous amount of grease was also applied to the bearings. Did you perhaps forget to install the seal behind the inner bearing?

Regards,
Hermann.

Hello Hermann,

vielen Dank fuer die schnelle Antwort. Ich weiss, dass ich den einzigen Passat habe, der Radlager frisst. Der erste Satz (ab Werk) hielt ca. 100000 km, danach ging das Elend los. Es wurden immer der komplette Reparatursatz eingebaut. Der Simmerring wurde zusaetzlich noch richtig dick mit Fett einbalsamiert. Die letzten haben etwas laenger gehalten, da wir ja einen trockenen Sommer hatten. Ich habe die Lager bestimmt schon 5 mal getauscht bzw. tauschen lassen. Ich werde jetzt mal ohne Lager versuchen mit dem Wasserschlauch das Leck zu finden. Last idea!!!

Best regards, Ide.

Hi Ide.
If the grease is in place and there's enough lubrication, the wheel bearing can only seize up if the axle journal is worn or damaged.
Measure the exact strength of the wheel axle or have it measured and compare it to that of a new one. Perhaps you're just looking in the wrong place.

What do you want to achieve with the garden hose?

Regards,
Hermann.

Hello Hermann,

The axle shaft looks good visually, and it also seems okay when sliding it in. However, I should measure it to be sure. Both sides are affected. The idea of using a water hose is definitely extreme. My theory is that the water must be entering through the openings in the brake caliper bracket, the handbrake cable, or through the gap to the brake drum, otherwise the entire brake wouldn't be so completely rusted. (it really looks bad, with proper corrosion). A seal could never allow that much water to enter. Also, the brakes seizing up quickly suggests a lot of water is involved.


Best regards,

The brake seizing quickly suggests a stiff brake lever or a tight handbrake cable. It's possible that the lever is stuck due to rust. However, these parts often become difficult to operate.
I find the idea of water flowing through the handbrake cable and into the drum to be quite vague. Furthermore, the cable ends in the lower part of the anchor plate.

Regards,
Hermann.

Hello Hermann,

The handbrake is extremely light when it works. For example: After driving in the rain, if you park the vehicle, after 2-3 days the brake becomes so tight that it needs to be 'released' while reversing. If you then engage the handbrake while driving, a rear wheel can lock up. To me, this is an indication that the drum has accumulated a lot of rust. Of course, the lever itself could also be stuck. My suspicion is that water is getting in somewhere significantly. This is certainly possible through the handbrake cable. The water enters the drum and is then evenly distributed by the rotating drum.
I'm also stuck and don't know what else to do besides swapping the components.
What is the price of a used rear axle?

Best regards, Ide.

...they actually don't exist at all!
Hi everyone!
If your wheel hub trunnions are indeed so worn that no bearing can be fitted on them, you definitely don't have to replace the entire axle. It is sufficient to replace the trunnions themselves. Caution: there are different types for the Passat, with varying camber values. Definitely do not (!) use those from the GT model, otherwise you will get a saw-tooth profile on the rear axle.
Okay, now let's talk about the rag trade...
Wenn du immer den kompletten Satz tauschst, sprich beide Lager, Simmering und Fettdeckel, dann dürfte dem Radlager Feuchtigkeit im Prinzip wurscht sein, es sei denn, du nutzt deinen Passi als Amphibienfahrzeug . Was aber nicht wurscht ist, ist das Fetten der Lager. Und da kommt es auf das WIE an. Ich habe bei meinem alten Passat auch mal die schmerzhafte Erfahrung machen müssen, daß eine große, namhafte VW-Vertretung in München (nicht MAHAG) im Prinzip auch zu blöd dazu war, nach 30000km war es mir nicht mehr möglich, das Spiel einzustellen, da die Lager aufgrund Fettmangel zu sehr verschlissen waren . Richtig fetten heißt, alle Zwischenräume zwischen den Walzen mit Fett zu füllen. Geht folgendermassen: eine kleine Portion Fett (etwa daumenkuppengrosser Batzen, das reicht für 2 Lager leicht) in die eine Handfläche, dann das Lager mit der breiten Seite immer wieder auf das Fett drücken, so lange bis auf der anderen Seite das Fett zwischen den Walzen rausgedrückt wird. Dann in den Zwischenraum in der Trommel/Scheibe zwischen den beiden Lagern auch eine ordentliche Portion Fett packen, ebenso auf die Lagerschalen noch eine dünne Schicht. Zusammenstecken und den Simmering rein, fertig. I personally think that applying grease from the outside to the sealing ring is absolutely not a good idea, especially with drum brakes, as it should be quite obvious that this could negatively affect braking performance .
It's actually quite normal for the rest of your braking system not to look perfectly fresh over time; I've even seen proper blooming effects like you described on various brakes, even on French cars, and the drums are so encapsulated that they should practically be floating... It's also completely normal; due to heating, condensation forms at lower outside temperatures, and high humidity will find its way in during longer periods of inactivity. Also, it's important not to forget that different metals may be used depending on the manufacturer, or perhaps a brake cylinder was replaced while keeping the rest of the mechanism intact, both of which promote corrosion . Question: How old are your brake pads? Even if they still look good in terms of thickness, if the rest is as deteriorated as you described, it might be a good idea to replace them. You should lubricate your handbrake levers and all other moving parts with plenty of copper grease; this will usually give you peace of mind for the next while.I hope you were able to find something useful in my text.

Best regards,

Dominique.

Hello guys,

First of all, thank you for your efforts. I'm not telling you any bullshit here.
'There's still a small amount of brown/white sludge in the bearings, otherwise there's nothing but a few water droplets. I do a lot of maintenance on my vehicles myself, but not everything. Some of the bearings were replaced by a qualified mechanic while I was present. He just kept shaking his head. Of course, this replacement process is also going to be expensive in the long run. Just for information: it's a 35i Variant, engine 1Z, 66kW, original, with 245,000 km and I drive about 120 km daily.'

Best regards, Ide.

Hi Ide,

It's very important to adjust the bearings correctly . It's better to set them a little looser, and if you encounter strict inspectors at the TÜV (technical inspection authority), tighten them again. Then the bearings should last forever .

It's normal for the brakes to get stuck. I haven't seen a car yet (even brand new ones!) that hasn't had this problem. However, it should only occur in winter, in wet weather and on salted roads. Drum brakes are particularly susceptible. Therefore, I never engage the handbrake in winter.

I don't even use the handbrake anymore (unless I'm parked on a really steep hill).

Best regards, WarLord.

Why don't you get a new rear axle?
I own a Volkswagen Golf 3 TDI Variant with a 1Z engine, and I bought a used rear axle last week for just €70. They're not that expensive.
In my opinion, the same axle should fit your Passat.
Best regards, Michi.