JB74 rear wheel bearing change

Although I’ve done this, I haven’t photographed it properly (yet) so it’s text till I do that. This is based on the official service guidelines

Sections

Things you’ll need

  • Wheel bearing, retainer ring, axle seal (parts listed below).
  • Silicone sealant: official spec is Threebond 1215
  • General tool kit with some spanners and sockets
  • Axle stands
  • Differential oil: see specs here
  • Brake fluid & a way to bleed the rear brakes
  • Grease
  • Slide hammer or a way to pull the axle out
  • Hammer and some way to protect the end of the axle when you tap it back in
  • A way to remove old bearings and seal e.g. angle grinder and cold chisel, or a bearing/gear puller
  • A way to refit bearings (e.g. press, or a long piece of pipe) and seals (e.g. seal driver or PVC pipe)

Genuine versus aftermarket / gen3 versus gen4

A common question is if the gen3 bearings are the same as the gen4 bearings, or if there’s any difference with aftermarket and genuine bearings or bearing kits.

After examining a bunch of parts diagrams, there appears to be little to no difference:

  • Bearings are the same part number (09269-35009; which is Koyo DG357222DW)
  • Retainers/ABS tone rings are the same part # as gen3 ABS parts (43485-76J00)
  • Axle seals are different part numbers (and gen4 superseeded from original parts diagram) but dimensions are reported to be the same +/- 1mm thickness on some gen3 parts diagrams (09283-48007 vs. 09282-48006 superseeded to 43491-82M00)
  • Seal protectors are the same part numbers (43588-73000)

Some of these parts are shared with other Suzukis beyond Jimnys, but I didn’t dive very deep into this.

The bearings themselves are interesting in that they are almost 6200 series metric deep groove ball bearings. A 6207 bearing is 35mm ID, 72mm OD, and 17mm thick; the Jimny wheel bearing has another 5mm of the inner race protruding out one side. This sets the bearing position along the axle to correctly fit in the housing. The Jimny wheel bearing is also steel seal on the diff side of the bearing and then a rubber seal on the wheel side of the bearing. The protruding inner race, plus the seal differences, means this is not a bearing you will find on a generic bearing shelf, although it is made by Koyo in Japan (as stated above, their OE part # is DG357222DW).

As you have to grind the bearing retainer off the axle to remove it, you require one to replace your bearing. This might be a difference with generic kits rather than genuine kits, as there are a number of specific features to the bearing retainer that make it a bit more complex than a simple spacer:

  1. The ABS tone ring presumably needs the same number of teeth to correctly work; there are 38 on the genuine retainer. This would need to match what the car is expecting not just for side to side comparisons but also front to back wheel speed comparisons for ESP/TC reasons.
  2. The tone ring end of the retainer has a 0.44mm protrusion, which ensures that the retainer only loads the inner race of the bearing without touching the metal seal. The distance from the inner race to the seal might also vary with non-Koyo bearings so might be worth investigating deeper
  3. The inner diameters vary. The diff/axle end of the retainer has an ID of ~35.10mm, whereas the ABS tone ring/wheel end is 34.90mm. This means that the press fit is only on half of the retainer (and critically – on the bearing end of the retainer).
  4. The outer diameter of the axle/diff end of the retainer fits inside the axle seal, so you need to make sure this matches the seal. The factory retainer measures exactly 48.00mm on my micrometer.

Factory parts

I bought a factory set of bearings, which included getting whatever parts have been superseeded according to the latest internal parts diagrams. The following is what I was supplied:

You potentially do not need the seal protector, but the other 3 parts are definitely needed. The axle seal is the only part that comes up with a different part number to a gen3 bearing set, and potentially is overall the same dimensions as a gen3 seal. Note that this seal is on the inside of the axle housing, so isn’t involved in mud/dirt/water getting into the bearing.

Potentially it is cheaper to source the genuine bearings direct from Koyo. They are ~$150 retail per bearing through Suzuki and maybe about $65 each through Koyo. If you’re on a budget but worried about non-genuine bearings, this would be the route I would go if you have the time to wait for one to come through a Koyo retailer.

Aftermarket set

I’ve currently got an aftermarket set on order to do a comparison. I will source a few of these from a few sellers to see if there’s any variance.

Diagnosing a bad bearing

The official procedure to diagnose a bad wheel bearing is to measure the end float at the axle, with the rear brake drum taken off. If the axle can move in and out more than 0.8mm then the bearing requires replacement.

Usually when a bearing is bad, you can diagnose it by seeing if the rear wheel has play. This is best done with the handbrake off, though if it’s really bad you’ll still feel it with the handbrake on. Grab the wheel at the top and bottom, or at the front and back, and see if you can move the entire thing. It’ll wiggle noticeably if the bearing is bad.

As an additional check, rotating the rear wheel with the car in neutral & the handbrake off can reveal a bad bearing as it might feel quite crunchy. This is the hardest thing to check/feel and also the hardest to illustrate here, but it can often be easier to feel it rather than see movement if the bearing is mostly making a whining noise rather than a clunking noise.

Destroyed wheel bearings mean that potentially the rear brakes will wear excessively – the play on the bearing means the drum ends up differently spaced to the brake shoes. As the brake adjusts up but one runs out of adjustment, you will find one side needs to be pulled more than the other. This manifsets itself as a ’tilt’ to the handbrake balance bar, which should be no more than 15º off perpendicular to the cable from the handbrake lever. While this isn’t diagnostic of just a wheel bearing (your brakes might have worn out on one side from lots of 4wding, or, your brakes have been stuck on from mud and stuff in the brake), it is worth investigating and going deeper than just replacing the brakes.

Pic from Trinity Vitetta – this is a nice example of a handbrake balance bar that is a bit unhappy

A final thing you might see with a badly failed bearing is the axle seal will start leaking and so you’ll have diff oil all down the back of the brakes. Once they get this bad, you’re not far away from the entire assembling yeeting itself out of there, though – and when that happens the wheel and the axle are going to go for a merry wander down the road.

Removing axle

Start by lifting the car up and supporting it on stands. Can be supported by the chassis or the axle housing; you will be pulling hard on the axle housing later on, but supporting it there means you don’t have to lift it as high.

Drain the differential oil. To make sure you don’t have a problem when it comes to refilling, first remove the fill point on the differential and then undo the diff drain plug.

Remove the rear wheel.

Remove the brake drum.

Remove the brake shoes.

Disconnect handbrake cable.

Undo the brake hose from the back of the brake, and plug it up with the rubber cap which covers the bleed nipple.

Remove the brake backing plate nuts

Pull out the axle – this can take some force and is easiest with a slide hammer attached to the wheel studs on the end of the axle.

Pull the oil seal out of the axle housing. This can be a bit of a pain, you need something to grab the inside of the seal.

Removing old bearings

Removing the old bearings can be a bit of a challenge. First off, the bearing retaining ring (which is also the ABS tone ring for the back).

The official method is to pull the bearing off the axle using a long puller, but you can also grind into the bearing with an angle grinder (again being careful to not nick the axle with the grinder) and then break it with a cold chisel. People suggest doing this to grind a flat into the bearing to make it easier to see when you’re about to break through – you will get ‘hot spots’ once you’re close to getting the axle. The wall thickness of the front part of the retainer is around 6.45mm, and the back part behind the ABS tone ring is 9.95mm.

Fitting new bearings and seals

Fitting officially requires a press. To make this job easier on yourself you can heat the bearing and the retaining ring up in the oven and cool the axle with some freezer spray or ice packs to use thermal expansion/contraction to help.

If you are lucky, it’ll just drop straight on. I’m never that lucky.

In theory, it would be possible to knock the bearing on with a hammer and a long piece of pipe that carefully fits just onto the bearing inner race, but you need to be careful to get it on the shaft nice and straight.

To press it on, you need a press tall enough to accommodate the axle. It doesn’t take a lot of force so a small shop press can do it, but you need to be able to accommodate the length of the axle too.

The required diameter of the pipe to push on the bearing and the bearing retainer is:

  • At least 35mm internal diameter, ideally 35.5mm
  • Ideal wall thickness around 4mm
  • A little under 46mm external diameter so it doesn’t press on the bearing seal, if not a little smaller

Refitting axle

Drive in the axle housing axle seal. The outer face of the seal should be between 35.7 and 36.7mm in from the face of the axle housing.

Grease the inner lip of the seal.

Apply sealant to the axle housing face all around the face

Tap the axle in using a hammer/piece of wood/soft bearing driver

Tighten brake backing plate nuts up to 27 Nm

Most of the rear brake is covered by putting things back together in my rear brake article, but you kinda do this:

Refit brake pipe to the brake wheel cylinder; this flare nut is torqued to 16 Nm if you have crows-foot adapters for your torque wrench

Reconnect handbrake cable

Reinstall brake components. This is really painful, the springs are a nightmare to get on.

Refill differential oil

Bleed brakes and adjust handbrake


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