Rear wheel bearing replacement

[carrera]

A week or so ago I used the TTiD as a towcar, for which purpose it performed well. However on the way home I started to hear some grumbling noise 

I put her on the ramp to diagnose the source of the noise. Helpfully WIS comments that diagnosing such noises, especially on AWD vehicles can be challenging for the most competent technicians. Oh great.

No possibility to spin the rear wheels without spinning the rear driveshafts/diff as part of a process of elimination then. Anyway, I dediced that the right rear seemed a little grumbly so removed the brake caliper to eliminate pad noise & decided that was the source. On the basis that if one was expired, I might as well do the other side at the same time, after all, it's only 3 bolts holding the hub on.

I spend the whole day yesterday trying to do one side. Tights / rusty bolts everywhere, the most challenging of which was the bottom end of the droplink. The only way to unscrew this was by use of a long breaker bar, for the entire length of the protuding rod. Lots of PlusGas and wire brushing helped, but only a little.

This was necessary because the bearing assembly would not come out of the hub. Searches for advice on Insignias showed that this was a common problem.... unless you have the right gear. The right gear being very expensive. Like this https://www.youtube.com/watch?v=issx1ptVnSo

With the driveshaft now cabable of being moved out of the way, this meant I could use my 10t Portapower hydraulic ram to press the bearing out. With the connecting links back in place, a chunky bit of box section inseted between the ram and the inner chassis mounting points, with wooden supports in the right place force was applied. The bearing did not budge, even though upon removal the box section was deforming 

I decided to remove the hub, which resulted in sacrificing the ABS sensor. My fault, I tried to withdraw it from the outside instead of tapping from the inside. Of course the Saab ABS sensor is different & more expensive than the Insignia ones. They are even different part numbers if the car has adaptive damping !

Anyway, I'm open to suggstions as to how to get the bearing out. I have seen the method using nuts / bolts through the stud holes to exert force, I might take it to a garage for them to press out tomorrow (the main reason for removing the hub to make the problem portable). In the meantime I'm building up to another attempt, but this time with a bigger hammer.

I also considered cutting through the bearing, but concluded that the hardened bearing metal would simply laugh at hand tools. I do have an air chisel

Fundamentally, I suspect that what we have here is corrosion between the steel bearing outer & the aluminium hub EDIT: The hubs are steel, so no dissimilar metals here, but rust has allowed exchange of material between bearing and hub
     

[carrera]

Well after a little more thinking time & watching YouTube videos where there were comments like "garages near me won't do that type of work", I decided to do some field engineeering

It's been a while since I weighed the scrap in, so I have a few brake discs to play with.

Small lump hammer on the back of the bearing, long hammer being brought down on it with two hands, and she's off. Actually there was some hammering & application of fluids before the photo was taken, with increasing amounts of aggression. I spotted that it had moved, and it was out 3 blows later.

I sacrificed the backing plate to be able to provide firm support. The base of it was a bit crinkley anyway, so am now busy with the various tools bringing the inner face to a good condition. New one (Insignia) should be here is a couple of days.

At least I don't have to go round garages tomorrow asking for assistance, the ABS connector is the critical item. I'll speak to Bill Jones tomorrow & see just how quickly they can get one from Sweden 

Now, where's the anti seize compound..... and what will I do about the nearside rear ?

[carrera]

This is a good reference video for all the potential methods without custom tools. The Saab special tool 49400 seems to be designed to operate against the driveshaft ends. How that works with rear hubs on a FWD car isn't clear to me...

https://www.youtube.com/watch?v=JKcgXmX8oBo

[sgould]

Using all that force radially would worry me.  You could end up with a bent driveshaft.

On the early 9-5 the front bearings were replaceable.  Saab recommended a 12 tonne press.

[carrera]

Indeed... or smashed CV cages

Though I haven't actually seen the tool, so I'm just figuring it out from the illustration in WIS

I did the fronts of JeffTheChef's 9-5. They were nowhere near as challenging, and I don't remember removing the ABS sensors, so they must have been done on the car. Quite a transformation in NVH

I'm sure that the OEM tools are fine with new components. It's the corrosion that increases the forces required, which could be avoided if some anto corrosion product was added at the manufacturing stage. But that doesn't make volume manufacturing cheap.

[carrera]

Parts are ordered to get the car back o the road

Neither Saab or Vauxhall have the ABS sensor for the AWD in stock (I believe it's 25mm longer), so I have had to go aftermarket. Got a pair, just in case

New brake backing plate should be here midweek as well. I think I'll see how things are before considering tackling the left hand side

[Audax]

Just buy the parts so you're ready, then you can be sure it'll never fail... unless it's the day before you're about to go on holiday or a long journey

[carrera]

Some deliveries today, they're no good in the box, so best fit them

Looking nice, though it's a bit of a juggling job getting the various suspensions bolts in line. At least the rear springs don't have a huge potential for anger if they slip when refitting

Just awaiting the aftermarket ABS sensors, which were promised for today, but I was never really convinced by

[Geoff1951]

Nice shiny things!

[carrera]

Thanks 

Today I rebuilt the brake caliper as the dust cover was out of place, which caused the piston to be difficult to turn. I reused the seals, which seemed to be in OK condition, but I'll probably buy a set to have on the shelf

There was some corrosion on the rear wing, which I treated with Bilt Hamber, before zinc priming & putting a first coat of base colour on. There'll be some further painting & polishing, but it looks far better already

Still waiting for the ABS sensors ....

[carrera]

The ABS sensors arrived this afternoon

Nice easy job, put the sensor in place, one screw to fix, run the cable to the connector, 15 minute job ? Nah 

The cable is routed along a suspension arm, over a mount, down to another suspension mount, back out to the inner wing and up to the connector. There are 5 plastic securing clips which push through hole, where there is either zero, or very little arm access, let alone tools. I ended up snipping or sawing through most of the old ones. Getting the new ones located & pressed in place is not an easy job, but I just have one difficult one to do & was able to find where it needs to be located using my small angled telescopic mirror

Tomorrow, she should be back on the floor, but I may as well put the Summer wheels / tyres back on before I do

Fingers crossed

[carrera]

She's all back together, on Summer wheels & I bravely decided to give her a wash before venturing out on a road test.

All good, the noise is gone & no new gremlins 

As this is quite a substantial job, thanks to corrosion, I have decided to leave the other side until it is needed, additionally, the one in stock is also suitable for the front should that be the next one to go

[sgould]

The XWD 9-3 is the same. All four wheel bearings can be interchanged.