Hello. I have been told (supposedly by experienced shop) that the front upper and lower ball joints for an XJ40 are "upgraded" ones that are also for the 420 (s-type, later MkII, etc.) and are an exact fit. Do you agree? Thanks.

Rob

 

They are absolutely right, its a no-brainer to use these Lemforder units to replace top and bottom.

The top one looks the same as the old one without the greas nipple and is a simple swap out, but the lower one is completely different. Replacing the bottom ball joint with the new type is very simple, I did them on my old XJ6. You undo the old joint and remove, then carefully knock out the ball seating ring in the hub carrier, (you must do this or the new joint won't fit properly) then replace with the new joint. New joints should come with the shorter bolts with blue thread lock on them, the old tab washers are not used any more.

The new joints cost less and last almost forever, what's not to like ?

 

Ill be doing this on my S-type soon. Yay!

 

Thanks guys. Let me know if I can help with anything - ran restoration shop for years almost all Jaguars. Take care.
Robert

 

Guys, old thread but hopefully someone can answer. I took out the old lower ball joint and there's a bunch of shims under it. Are these reused with the upgraded ball joint, or no? I heard on a youtube video that they where taken out as the ball joint wears, another states they are for suspension angle adjustment?

-David

 

No, you throw them away, they are only there to adjust the ball clearance in the socket. You must also tap out the ball-joint seating ring that is a light press fit in the hubcarrier. A few taps from the top with a hammer will get it out. The old-type ball presses against this at its upper side and against the Railco socket insert on the lower side. The Lemforder joint just bolts on and then lasts forever, (or almost !!). The fixing to the wishbone protrudes through the hole where the ring was, but there is no contact, all bearing surfaces are internal to the joint. The newer balljoint needs shorter screws which should come with the joint. No tabwashers are used, the bolts will have a blue coating of thread lock on them.