Wanted XM rear rotors

[XMdownunder]

Hello gents I am looking for a set of rear rotors for my 1998 V6 XM hatch.
The fitted rotors are worn out and measure 232mm dia and 5mm remaining I suppose they started as 9mm.
Any suggestions most welcome.
Happy Christmas Stephen Tasmania

[DownUnderXM]

OK- here is a discussion from this forum about rear brakes:

viewtopic.php?t=9148

and here is a link to an exploded parts diagram for our cars:

https://catalogs.ssg.asia/citroen/?lang ... BwbGllcj09

Part # is 4246T3, or E169255 for a pair. Tried a few Australian on-line sites without success (I can and do get some stuff for my Pug 406 from local sites), so then checked my reliable supplier - Spareto (in Estonia).

https://spareto.com/products?keywords=4246T3

4 different brands in stock! Note that all pictures illustrate a pair of rotors, but the text says clearly that the quoted price is for one rotor.
As always, their prices for the items are very competitive - it's the freight that hurts! However you will find you can add other stuff to the parcel without having to pay extra freight, so it won't hurt so much...

Alvadi also has them, and I believe offers more freight options (although cheaper will be slower - the longer they sit around in transit, the more chance for things to go wrong).

Cheers
Alec

[XMdownunder]

Brilliant thanks Alec I had run out of ideas who to ask.
regards Stephen

[XMdownunder]

That discussion provided great info thanks Alec. The gurus say Citroen fitted XM with 288mm and 232mm rotors from ORGA 7483 onwards however my XM is ORGA 7476 and is fitted with 288 and 232 rotors. If the ORGA 7483 is an unbreakable rule I will assume my XM was factory built with 225 rotors and happily replace the existing 232 with 225 rotors. If the ORGA 7483 build is flexible and is possible my 232 rotors are factory fitted I would prefer to replace like for like. All the 4246T3 discs on spareto site are listed as 225mm, are 232 rotors not available anymore?

[DownUnderXM]

Ok - you got me there - I replaced all rotors and pads after I got my XM in 2019, and I have no recollection of any issues/arguments about the rear rotor size! I have no recollection of previously reading about that change during 1998. As you say, Spareto has no mention of alternative sizes (apart from 250mm for the wagons) - Autodoc (who have a huge range of brands on offer) also only specify 224 (or 223.6)mm. None are actually specified as 225mm, but I'll put that down to rounding error .

So you've forced me into a little research. I have just been out and gone through my stack of old rotors (not as much daylight as you get in Tassie, but we manage). I found a set of 224mm rotors and a set of 250mm - these would both be from Xantiae (hatch & wagon). I also found a set of 232mm - clearly off my XM.

So then I dug through my receipts - my replacement rear disks came from Autodoc (who were happy to ship to Australia pre-Covid and pre-Brexit) and are 224mm!! (BREMBO 08.5352.10 Brake disc for CITROËN XM Rear Axle, 224x9mm).

I know I fitted them, and did not notice any problem with the disk pad sticking out beyond the edge of the rotor.

Careful inspection (and measurement) of the old 232mm rotors has shed a bit of light - my old rotors have a wider lip than normal - actually 4mm on each side, so the rotor is effectively 8mm wider than required by the pads. Perhaps the larger rotors did have slightly larger pads supplied at the time, which are also not made any more?

[XMdownunder]

Mmmm you did burn the candle down a bit last night thankyou. Maybe I am being a bit special worrying about the difference between 232 and 224 rotors (apologies the 225 rotor was created by my failing short term memory) but I was thinking about the possibility of mismatch between rotor and caliper. Question did Citroen use a larger caliper post ORGA 7483 to match the 232 rotors or did they use same caliper as for the 224 rotors?

[DownUnderXM]

Here's the top level of the parts diagrams - gives choice of Series I and Series II, then you choose engine etc and drill down - these are copies of the official PSA parts diagrams.

https://catalogs.ssg.asia/citroen/?lang=en#

My own research showed different pads (& therefore I assume different calipers) for Series I & II, but I could not find anything on changes within Series II.

Just a further thought from looking at my old rotors. Since the car had only done about 170,000km when I bought it, and the rear brakes are not known for rapid wear, I would expect that the rotors I took off were original. As I said, the pads fitted did not use the entire disk area, but if these were replacement pads, and smaller than the originals, I would expect to see a 'step' in the lip.

Here are my observations: on one surface (of the 4) there is a very narrow, but quite clear, lip right on the edge of the rotor (ie on top of the 4 mm wide lip). The other three sides have just the wide lip. The thickness measured on the lip is about 8mm for the rotor with the stepped lip, and about 7.5mm on the other rotor. So I think there is some evidence of correctly fitting OEM pads from new, replaced at some point with the smaller ones.

What story do your rotors and their lips reveal?

The remaining rotor thickness on my 232mm rotors is about 6.5 - 7mm, so if they are better than yours you are welcome to them, but they are rusty, and if you are able to source the larger pads you would need to have the lip(s) machined off.

I don't believe there was a caliper change, or if there was, it was backwards-compatible, as I'm sure my calipers are original. Personally, unless you come across a supply of the original slightly larger pads, there is no point trying to source 232mm rotors - you are just going to have slightly increased unsprung weight for no gain in braking performance.

[Dieselman]

All Es9j engines saloons were fitted with 232mm rear disks, irrespective of Rp number.

I'm not sure why you might think differently.

[DownUnderXM]

All Es9j engines saloons were fitted with 232mm rear disks, irrespective of Rp number.

I'm not sure why you might think differently.

Point remains that, although they may be specified as 232mm in the parts diagram, what is on offer from the auto factors for part # 4246T3 or E169255 are universally 224mm rotors.

Do you know of a source of 232mm rotors? What about matching pads for the larger rotors? Does it matter? My experience is that it does not seem to matter...

I'll leave it Stephen to explain where he found a reference to a changeover to the larger rotors on an ORGA/date later than that of his car.

[citroenxm]

The rear discs are still fairly readily available on our eBay.co.uk but care needs to be taken on the quaility being bought.

I was under the impression that all HATCH/SALOON xm used the same rear disc and oad without any changes no matter what engine was fitted be it 2.1td, 2.0 tct turbo, 2.0i etc etc .. where the estate (Wagon down your way) had larger caliper and pads due to the larger load area...