How to Replace wheel bearing kenworth truck?

Answer 1

You didn't specify which axle, so I'm going to take the liberty to assume you're referring to a Dana-Spicer drive axle.

Here's what you'll need...

22mm socket

4" steel socket

Tire removal tools... either a 3/4" or 1" impact (or ratchets, if you're patient) and 33mm socket

Torque wrench(es) capable of measuring 50 ft/lbs - 300 ft/lbs and capable of mounting the 4" steel socket

Slotted screwdriver.

Brake adjustment tools (depends on which style slack adjuster you have)

1/4" hex (Allen) socket and corresponding ratchet (typically a 3/8" drive)

Dry solvent tank or brake cleaner (and plenty of it... personally, I prefer to use a pneumatic Sure-Shot over aerosol cans)

Ratchets

Impact wrench for the 22mm socket (optional if you have a ratchet which works with it)

Gasket removal tools - either an angle or die grinder with surface conditioning pad or wire brush, or else a gasket scraper and spray-on gasket remover

Chock a wheel which won't be lifted off the ground. Raise the axle with the wheel where the bearings are being replaced. Remove the tires and wheels.. you'll need either a 3/4" or 1" drive impact and a 33mm socket for this... set those aside.

Release the brakes, and adjust the slacks all the way off... what you need for this depends on what type of slack adjusters you have... Haldex slacks require a 7/16" wrench or brake adjustment tool, while the Bendix ones typically, require a 9/16" tool, plus a small slotted screwdriver or set of sidecutters to pull the pin back to allow adjustment.

Once you've got your slacks backed all the way off, hit the brake drum with a heavy hammer until it dislodges, then remove the brake drum. If you want to remove the brake shoes at this point, although you really don't have to unless the shoes are contaminated (such as oil from a blow wheel seal).

I believe it's a 22mm socket you'll need to remove the nuts for the axle shaft.. set a drain pan under it before you loosen them, because gear oil will spill out.

Pull out the axle shaft and set it aside.

Once you do that, you'll see the hardware which holds the spindle on. You'll need a 4" steel socket and a ratchet to turn it... a 3/4" or 1" ratchet works best, but I typically use a 3/4" drive steel socket and a long-handled 1/2" Snap-On ratchet with a 1/2" to 3/4" adapter.

First, you'll notice a sprocket-like ring behind the nut with flaps folded over the outer nut. Fold those back with a slotted screwdriver. Then you remove the nut with your 4" socket and ratchet. Once that's removed, you'll pull off the aforementioned sprocket-like ring, as well as a perforated round ring with a plastic oil agitator ring atop it. Then you'll expose the inner nut. Use your 4" socket and ratchet to remove that.

At this point, you'll have to shake the spindle around and possibly use a slotted screwdriver to get the outer bearing out. Once that's done, you'll have to pull hard on the spindle to get it off the axle.. this will also push the cone forward, which you can remove either before you take the spindle off, or afterwards.

Once you have the spindle off, lay the outer end down on the ground, and you'll have to remove the wheel seal... you can use a regular carpenter's prybar to remove this... pull it out, and, once that's done, you can take the inner bearing out.

Sometimes, a part of the wheel seal will remain affixed to the axle... a set of channel locks is a good tool to remove this.

Now, you clean the bearings and inspect them.. use either dry solvent or brake cleaner. If you see pitting in the rollers or difficulty turning the rollers, yep, they gotta go. In which case, you also have to replace the races, as well.

Driving out the races can be a real PItA... I use a MIG welder to run an arc along the inner edge of the races.. this lets the spindle expand enough to make it a lot easier to remove the races. Drive them out with a race punch and hammer.

Now, if you've already decided you'll be replacing the bearings, go ahead and do two things: first, let the bearings soak in some 75W-90 gear oil. Second, put the races in the freezer, and let them sit in there for at least an hour.

Clean out the spindle really well. Remove the axle flange gasket (you might need a grinder and surface conditioning pad for this, or a gasket scraper and some spray on gasket remover will do). Afterwards, wash thoroughly either with brake cleaner or dry solvent, and wipe dry.

If you don't have a tool to drive the races in, grind the outside corners of the large sides of the races down and at an angle.

Now, you install the races. Take them out of the freezer.. larger race goes to the inner side of the spindle, smaller goes to the outer. Use your modified races and place them atop the new races... you can use a hammer and your race punch to drive them in, but make sure you drive them in evenly.

Once that's done, install the inner bearing. Once that's seated, you have to install a new wheel seal.. for 20k Dana-Spicer axles, I don't have a cross reference handy, but we use the Stemco 393-0173. You'll also need a driver and rubber mallet to drive this in, and, again, make sure you drive it in evenly.

Make sure you've cleaned off the axle, and it wouldn't hurt to give it a once over with some emery cloth. Me, personally, I like to lube it up with some 75W-90 gear oil before I put the spindle back on. Once you mount the spindle, push it in as far as you can get it.

Now take the cone... clean it off with some dry solvent or brake wash (if you're using a dry solvent tank, go ahead and clean off all the parts, and keep them wrapped up in some clean shop rags afterwards).

Install the cone.. small end to the outer part of the spindle... then you install the outer bearing (the smaller one).

Once that's done, you'll take the inner spindle nut (you'll be able to tell the difference because this one will have a nipple on it, which goes through one of the holes in the perforated metal ring I mentioned earlier). Make sure the nipple points towards the outside (away from the wheel seal). Now you'll need a torque wrench... with your torque wrench and 4" steel socket, torque the inner spindle nut to 300 ft/lbs (approx 407 Newton Meters). This will seat the spindle.

Once you've done that, back the inner spindle nut off (don't use the torque wrench for this), then re-torque it to 50 ft/lbs (68 Newton Meters). You may have to torque it slightly past this point to adjust for the perforated metal ring... the perforated metal ring goes on next... the nipple on the inner spindle nut should seat perfectly into one of the holes in that ring... if it doesn't, torque the nut again slightly until it lines up.

The plastic oil agitation ring sits atop the perforated ring, lettering facing out. After that, you put the sprocket-like ring on, then the outer spindle nut. Torque the outer spindle nut to 250 ft/lbs (339 Newton Meters). Then fold at least two of the flaps from the sprocket-like ring over the outer spindle nut with a slotted screwdriver.

Next, you put your new axle flange gasket on over the studs for the axle shaft. Then you insert the axle shaft (you'll need to manipulate the inner end up a bit to insert it). Once you've got the axle shaft installed, put the washers and nuts back on the studs, and torque them down tightly.

The fill plug is on the spindle.. rotate the spindle until it's on top, and loosen it with a 1/4" hex (Allen) bit and ratchet. Put two quarts of 75W-90 gear oil into the spindle, then rotate it to where the fill plug is parallel to the ground. If oil comes out at this point, you have enough. If not, add another quart and repeat until oil comes out of the fill plug when parallel to the ground.

Replace the fill plug.

The rest from here is reinstalling your brake shoes (or replacing the brake shoes altogether).. if you're keeping your existing brake shoes, I'd recommend you still replace the hardware kit (S-cam rollers and springs).