Front Hubs

Unlike your car or light pickup truck the front hubs and bearings on our chassis are not sealed and good for life, they’re not even serviceable with a grease gun like your trailer, they are oil filled. And it’s on the list, items 33-05 and 33-06. Check at the first 6000 mile service, then every 12 thereafter. Change at 12, then every 24 thereafter.

Sounds daunting…. it isn’t. But it’s important. If there’s a leak and all fluid drains out 1: The hub will self destruct with the wheel possibly coming off…. And 2: All that oil will render your brakes on that corner pretty much useless. So…. check we do. And if you see a puddle there…. STOP and investigate.

Here’s how…….

Remove the center hub cap. I use a plastic upholstery tool, a plastic putty knife can work to get it started or just use a fine screwdriver and be careful

Now remove the rubber cap in the center. Look very carefully at the plastic “window”….. there’s two rings on there and they are labeled, with an arrow, as the min and max. Mine was a little low so I added. (Min to MAX is about a half a shot glass, so go easy). The book calls for an extreme pressure 80/90 gear oil. Use your favorite flavor, I used Valvoline, it’s a good brand. This is what it should look like.


Note the ribbed plug in the bottom right hand corner of the picture. That’s the drain plug which we will be using to change the oil next installment. For now, put the plug and the hubcap back on, give the wheel a polish and motor on!


And then it came time to change the oil. Pretty straight forward. I used the levelers to get the front wheels off the ground and get the drain plug UP. I removed it using a 5/16″ allen wrench. Then I turned the opening down into a “flexible funnel”.

Let it drip dry. Now, if you look at the plug you will see black “stuff”. If you wipe it off with a rag you will see shiny metal pieces. I am going to assume this is normal, just like a differential. The plug is magnetic and collects whatever wear and tear occurs. There’s some running in from new, and that leaves “shavings”. A blast with air will take it off.

I then put the hole back up and the plug back in. Book (33-05) specifies a torque, 25lb-INCHES. I don’t have the tool to get the torque wrench in there (it’s a tight spot) so I used what the Brits in the 50’s called “fitters feel” and put them in finger tight plus a quarter turn. (About how they came out.)

Now it’s time to fill. It is very important that the axle is level side to side. (Not the bus…… the axle). My driveway slopes quite a bit, right to left. So I used the levelers to bring the left side up enough to take the weight off the left wheel, and then I used a floor jack under the axle to get it level, using a 2′ level to verify. (Independent front suspension will have other requirements).

Then it was filling time. Took one big squirt and 10 or so little ones before it stopped settling down. How much? The white bowl in the picture is one hub so, not a lot. A quart bottle should do at least two changes. Put the cap back on and presto. Done.