XK140 front control arm bushings

I am starting rebuild on my 56 XK140 suspension. I have removed the previous Metalastik bushings–which wasn’t easy as they were tight on the carrier shafts. I have ordered two sets of new bushings. The first was loose; the second snug but not nearly as tight as what came off. I assume these bushing sleeves are not supposed to turn on the shafts–but am I over emphasizing this? Have others had similar issues? And opinions on rubber vs poly? Thanks

Snug is about right. I had to cut my originals off with a hammer and chisel.
I prefer rubber. The new parts have been on there 25 years and will outlast me.

Since the shaft has splines on it, I assumed the bushing was not supposed to turn on the shaft. Is that correct? Thanks

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Yes, that’s correct.
I should have mentioned my old ones were pretty rusty and hard to get off.

Yes, when I removed the old ones on my car I had to burn the rubber off, then carefully saw through and peel off the old ones. Shaft and bush were splined. The new ones required pressing on and are firm on the shafts.
I really don’t like polybushes on old cars. The suspension was all designed to work together, so changing one element can change the whole character of the car, not for the better. A rubber bush twists in action (hence the splines), whereas a Polybush won’t, so something must be giving somewhere. Why you might want to make an XK stiffer is not something I understand - I tend to think that if you’re looking for BMW levels of flat cornering, grip etc. it might have been a better idea to buy a BMW… A modern Mini will run rings around an XK anyway, no matter what you do to it.

Hi Roger…not all poly bushes are the same so its not correct to say that rubber twists but poly bushes dont…the black poly bushes sold by some of the usual suppliers and named as “Polybush” fit and operate in the same way as the originals and the poly compound is as close in characteristics as the original rubber…however beware what “poly bushes” you purchase as some are very hard and are made not to twist but instead slip/rotate around its central metal inner sleeve…Steve

Interesting, Steve - I’ve not seen any with enough ‘give’ to twist through full suspension travel. But that may be because I haven’t actually looked! Do they come with the splined steel bonded metal parts to ensure they don’t move? Personally I’ve always found buying them a bit of a quality minefield, and have always felt a notably harder ride with the ones I used to buy for TRs and Healeys etc. As I’m not racing, I decided long ago to stick with the closest material I could find to the original metalastiks etc.

Hi Roger…i used them quite a few times on E types…and have them for my 150…and know plenty of other’s thst use them…they arnt splined but the shafts arnt splined either… the shaftes have serations and tightening the nut to fully grips the inner and hold the sleeve…the sleeve is bonded to the outer poly…Steve