I’m doing a conversion to outboard vented rear disc brakes on my 87 XJS using XJ40 hubs and axles. Does anyone have a picture of the two body mounted flexible hose bracket locations, or point me to a link with one? I’d like to duplicate what the factory did as much as possible.
Thanks.
Yes that helps. I get the general idea.
Thanks!
You’re welcome.
PS Make sure you’ve got the correct alignment “spacers” to set the camber. The shims you’ve got from the inboard setup won’t work
Yeah, I grabbed everything, including spacers from the XJ40 when I pulled the hubs and axles. I’m rebuilding the hubs now. The lower wishbone pivot bearings were a rusty mess.
Have you been through this? I’ve found several threads where people talk about various aspects of the conversion, but nothing complete. I’m trying to document what I do, especially trickier aspects such as the spacers for the outer wishbones for the smaller pivot bolt on the XJ40, the parking brake setup, and adapting the hard brake lines fittings on the XJS to the outboard caliper flex lines.
No, my car has the factory setup, being one of the last v12’s with 6.0L.
But, the spacers you’ve got from the XJ40 are unlikely to give you the correct camber for the XJS.
Here, instead of adding/removing shims, one needs to swap spacers. Say you need to correct too negative camber to make it close to -1.0°. The existing spacer is 5 mm. Then, depending on how far off the actual value is, the 5 mm spacer should be replaced with 5.5, 6.0, 6.5 or even 7.0 mm.
The parts used in the XJS with TEVES III and TEVES IV (outboard brakes) are not compatible. Solid vs vented rotors, different caliper design, brake lines, pads, shoes - everything.
Not sure about XJ40. Won’t be surprised if it is also a mess in the catalogs.
Hah! The rear X brace goes under the axle! That makes sense! The description I got was that it went under the trunk, which made no sense to me.
I just recalled that Alan (aka lockheed) did the conversion to MY 96 brakes on his (or his wife’s) 89 coupe. He has certainly posted the notes and might be willing to do it again.
Paging @lockheed1
Fortunately, my 87 doesn’t have ABS, so I don’t have to worry about that. I figured out the various brake line adapters I need, and they are on the way. They use the same size brake line, but the end fittings, and sometimes the flares, are different.
Some places imply you can use the XJS half shafts with the XJ40 stub axles, but the u- joints appear to be different part numbers. Still need to figure that out. I’ll be pulling the IRS out in the next few days, and I’ll find out then when I pull off all the inboard brake stuff.
That’s a true statement by Steve. Attached is summary of what I did, and a few photos. More photos and commentary if needed.
XJS Outboard Rear Brakes conversion.pdf (77.5 KB)
Your car does not have an ABS, but what I wrote was with regard to the donor car, which did. Beware!
Lockheed1, those pictures help a lot. Thanks!
When I did my conversion I contemplated the XJ40 route, but ended up using a complete rear axle from a 1994 car. Rusty as hell, but I only needed the lower arms, half shafts, and hub carriers. I binned the solid disks, and found that the later X308 XJ12 had vented rotors and calipers that would fit my hubs. Not sure what you have on the XJ40 hubs, but is worth while considering an upgrade.
I’m fitting later vented discs and calipers to the XJ40 hubs. Only slight mods to the backing plates are required. Parking brake setup is the same.
Please correct me if I’m wrong: if I want to replace my solid rear discs with vented, I think I could use JLM20342/C2C41251 discs with JLM12426 & JLM12427 calipers. JLM2209 handbrake shoes appear common to both outboard rear brakes XJS & X308 models. That should only leave selecting the correct rear brake hoses as the X308 cars appear to be a squared off banjo type fitting whereas my existing rear brake hoses thread directly into the calipers.
Rgds.
Andy.
You also have to mod the backing plates, taking off a spot welded-on ridge on the face of the backing plate, and also open up the opening for the caliper slightly to clear the bigger caliper.
This link has a photo to the mod to remove the spot welded piece.
I’d like to say for certain what part numbers I used but it was a long time ago. One problem I’ve had in the UK, is cross reference of Jaguar to standard brake parts. Whatever third party part numbers you see, they are invariably wrong when cross referenced with OEM. I have a nice set of EBC yellow stuff pads to go on that outboard rear axle - DP4940R. They are labelled as front pads for a Daewoo Nexia / Lanos Espero. Took ages to reverse the parts look up and figure out that they are also the same as X308 XJ12 rears. And those handbrake shoes - invariably you will get handed something that is for a Peugeot/Citroen. But in this case they are different items, totally messed up cross reference in all the books.
Thanks for the responses. I’ve been down the road of Peugeot (605 I think) handbrake shoes which do not fit as they are obviously too wide just from looking at them.
The Jaguar price of £374.84 (inc. VAT!) for JLM2209 is nothing short of a hilarious attempt at daylight robbery. The items in question are worth about £20.00
Good advice regarding the backing plate modifications - thank you.
Rgds.
Andy.
Andy:
You got the shoes for the vented rotors, when you in fact have solid (both outboard). We have been discussing this for ages.
Here (of course the tiny url’s are no long good)
and here
For posterity. Solid outboard rotors - JLM2209 → the correct shoes are CENTRIC 11108260.
I verified that Jaguar’s electronic parts manual specifies JLM2209 for both vented and unvented outboard parking brake shoes. The vented rotor could accommodate a wider shoe. I tried looking up the Beck Arnley part number that was listed for the wider shoes, but most links say unavailable. I think I’ll stick with the Centric JLM2209 equivalent. BTW, Rock Auto lists the Centric 11108260 shoes for the vented outboard discs.