weird tyre defect [pic added!]

deian · Post by **deian** » 17 Jun 2007, 12:10

Ok thanks for that alan s, i shall investigate any issues today (if the weather holds up, i don't want to be washed away by the rain).

Out of interest, can anyone tell me about the rear arm bearings? does £10 for the bearings sound like i found the right item on gsf/ecp?

and if they are bad i will need the rear arm repair kit (38 from ecp)...

or should i just be generous and get new arms anyway?

how big is the job? are there any special tools needed, what about time?

thanks again

AndersDK · Post by **AndersDK** » 17 Jun 2007, 12:26

deian wrote:Ok thanks for that alan s, i shall investigate any issues today (if the weather holds up, i don't want to be washed away by the rain).

Out of interest, can anyone tell me about the rear arm bearings? does £10 for the bearings sound like i found the right item on gsf/ecp?

and if they are bad i will need the rear arm repair kit (38 from ecp)...

or should i just be generous and get new arms anyway?

how big is the job? are there any special tools needed, what about time?

thanks again

£10 is for the bearing only. You will need new seals, new spacer tube and new tubular plastic sealer together with the bearings.
The lot comes in ready packed 'rear arm repair kit's for Xantia (saloon version ONLY).

My experience is that removing the old bearing races from the arm bore is the biggest challenge. Usually the old spacer tube can be used as a sharp edged 'chisel' tapping/hammering the races out from behind.
Note that the bearing races are hardened and thus crisp steel. One lucky blow, and they crumble.

Another common problem is removing the cylinder lock pin from the arm. The lock pin will snap if you just try bodge it out. It must be treated as a rotten egg, with lots of rust solution and small wriggles to losen it up.
Red heating it may do the trick.

BTW : I seem to remember that for the Break versions its the bearings and seals that are different. Remaining bits are exactly the same. But trying to source the remanining bits from Citroen is more expensive than buying the complete saloon repair kit.
Meaning even if you buy the saloon kit and source the break version bearings and seals - its cheaper than the break version parts from Citroen.

deian · Post by **deian** » 17 Jun 2007, 15:55

http://www.flickr.com/photos/deiz92/560135864/

After swapping the front and back tyres, the tracking is more or less spot on no. With the bad firehawk tyres that i swapped over to the front it was pulling to the right (steering had to be held at 11 o clock), even though the second time ATS said it was spot on. I guess the laser doesn't lie if set up properly, but it cannot see tyre defects obviously. Fair play though, the second time I went to ATS they guy checked the tyre pressures. Still no1 takes it for a test drive.

I didn't check the rear arms yet, the clouds look threatening at the moment.

Post by **RichardW** » 18 Jun 2007, 07:51

The NSR tyre on my Xantia is worn exactly like that, which makes it rumble / vibrate a bit. No idea what has caused it, but probably rear arm bearings / odd hydractive behaviour. Mind you the tyre is only a cheapo, and has been on that corner since I bought the car 2.5 years / 60k miles ago, so can't complain too much.

deian · Post by **deian** » 18 Jun 2007, 15:42

I don't think it's caused by rear arm bearings myself. I had a check last night and all seems quite stable, the car isn't loose from side to side and the wheels aren't leaning towards the front nor are they leaning out.

My cousin has the same symptoms on his tyres on his Mitsubishi Evo 6. The guy at ATS reckons it's random and quite unexplainable for many reasons,

...as AndersDK mentioned earlier in the thread, thumbs up to him (...again), thats not to say it may not be caused by the rear arms either, just it's 'probably' not the reason in my case, just a weird tyre on a weird car.

Post by **admiral51** » 18 Jun 2007, 16:16

just a wild stab in the dark at this but does the rim itself run true without a tyre on it
not sure if they are alloys but they can take a bit of punishment without showing any visible signs of damage
picture shows possible cracking on inner edge of rim
would imagine you can balance a wheel/tyre but if rim is not true then you will get minute wobble which can give odd/unexplained tyre wear
like i said just a stab in the dark
colin

Brian UK · Post by **Brian UK** » 18 Jun 2007, 17:07

What you also have to remember is that with all these front wheel drive cars, the rear tyres last for millenia. 50k miles is not unusual, and with very old tyres like this other problems do occur, such as uneven wear.
Assuming it is down to Citroen suspension, or trailing arm bearings might well be a total red herring.
Since, as I previously said, I had the same on my 307......

Post by **admiral51** » 18 Jun 2007, 18:10

just been having a nose about on the internet and found this whether this helps or not im not sure but may provide some useful info anyway
http://www.carbibles.com/tyre_bible.html

just scroll down and see what what you think
colin

Post by **philhoward** » 18 Jun 2007, 21:21

The pic suggests manufacturing defect to me...but looking at the cracks on the bottom of the treads, they're funstered. What's the date code on them? Something like "2303" - first two digits are the week; 2nd pair the year. Anything over 5/6 years old and they'll start to degrade/possibly delaminate.

has the car spent long periods laid up (not moving)? You can end up with minature flat spots which then cause odd wear patterns...

rory_perrett · Post by **rory_perrett** » 05 Jan 2008, 19:16

Bit of an update on this one.

After writing off two lefthand (nearside) tyres with an uneven wear pattern to the outer edge (see above) I decided that the rear arm bearing might be the problem. As described above there was no sign of the typical Citron wheel lean that my BX used to get every 100k ish miles. There were no squeaks, creaks or groans from the back. Jacking the car up and checking for roughness and play showed no apparent problems or movement but I went for it anyway as the car had done 208k miles (and I need a bit of excitement in my life).

When I got the arms off the bearing were in very good condition and still well packed with grease. Back to my BX days, I was used to having a rusty mess of disintegrated bearing drop out of the arm as I took it off. I was beginning to wonder if I’d wasted my time and money. To be honest at that stage if I hadn’t already bought the bearing kits from GSF I wouldn’t have bothered continuing, as signs of wear were minimal. (At one point I had contemplated taking an arm off to have a look at the condition before buying the kit as the lack of wheel lean or play was making me doubt that the job needed doing).

Anyway did the job, unfortunately managed to kill an ABS sensor in the process, and now 9k miles further on there is no sign of any uneven tyre wear as before. Unlike with the BX there was no dramatic (or particularly noticeable) improvement in the ride quality or handling after the change.

If it was the rear arm bearing I can only conclude that there was sufficient wear for there to be some movement in the rear suspension giving the wheel some positive camber for example when going round roundabouts.

Regards

Rory