the following question has brought me to this site. Maybe one of you can help me! I have an 05 X type that I am about to change the rear lower control arms in but, I cant find any (real) information regarding this. The process seems to be extremely simple but I want to know if the new ones will need to be torqued to a specific poundage when they are installed. If they do, what is it? Thanks

 

The job is indeed pretty straightforward and like almost all nuts/bolts on the X Type, there are specified torques. For the front lower arm of the rear suspension (Which is what I think you're going to change - the rear lower arm is the spring carrier) the torque for the bolt at each end is 85lbf.ft/115Nm.

It's important to do the final tightening of these bolts with the weight of the car on its wheels.

 

Thanks for answering my question and also for the added information about lowering it before i torqued the bolts! The nesesity of that would have never occured to me.
Still, not sure why that would make a difference since the weight would not be on the nuts but, in the end "why" doesn't really matter so much.
Thank you.

 

The outer diameter of the bush is fixed in the control arm while the inner steel sleeve is fixed to the mounting point. As the suspension moves it flexes the rubber. If you tighten the bolt while the wheel/suspension is hanging in its lowest position on a jack or axle stand, when the suspension deflects fully under load, the nice new bush will be twisted way beyond its design range and will have a very short life

 

Brief back story: A while back (3,500 miles +-) I noticed some wear on one of the front tires. Brought the car in to have the suspension looked over and for an alignment if necessary. I was told that it was and I had it done. Problem (seemingly) solved. No, They only did a front end alignment (brilliant).....
Noticed wear on the inside of rear right tire. changed out the lower front (rear end) control arms on both sides. Car seemed to perform great but as advised, I Brought the car in for another alignment (different garage, presumably more competent). I also asked them to look over the suspension and see if there was anything else that either needed replacing or would soon. They called this morning and said the alignment was "done" and everything looked fine but the rear camber (and now front as well) are out of adjustment.
I realize the rear is not adjustable (thought the front was). Either way, to say this is "done" and the suspension is fine seems like saying "these cars came off the lot misaligned and there's nothing you can do about it".
Can somebody please tell me what the problem likely is so I can avoid any more un-necessary expenses?
For what it's worth I've attached a copy of the print out from todays alignment

 

By the way Astromorg, I really appreciate the reply regarding the reasoning for torqueing under load. That makes absolute sense!

 

Experience seems to point to the camber problem often being the result of using non OEM parts that are dimensionally not quite the same as Jaguar ones - too long or too short!

Many have resorted to using a Volvo part at the rear that is adjustable. Thermo can give the details on that - I think it was him that did the research.