Difference between Bilstein B4-B6 shocks?
 

What is the difference between the Bilstein B4 and B6 shocks? When I was checking Rock Auto I saw they have them available for the XJR and also the Vanden Plas model. From what I read on their site the B4 is the oem shock and the B6 is the performance model, what does this mean? I knew there was a difference between the stock shocks on the Vanden Plas and the XJR but if you wanted to stiffen up the ride a little bit on the VP would the B6 shock be a better choice or the stock XJR shock? Has anyone tried the B6 shocks on the XJR model? This is for the 95-97 models.

Is the length of the XJR and the VP shocks the same so they would be interchangeable?

Hi Scotlad,

I have not tried the B6 version yet, but I've used the B4s on many normally-aspirated X300s, both short- and long-wheelbase, and they seem to provide the comfort and reasonably good handling we would expect from shocks that were original equipment on non-supercharged and non-sport models.

My assumption is that the B6 would provide a stiffer ride and improved handling at some expense of comfort, probably similar to the "sport" shocks that were original equipment on supercharged and Sport models, but tuned to work with the OE comfort springs rather than the stiffer springs that were installed on the supercharged cars.

Hopefully one or more of our members will be able to provide more knowledgeable answers.

Cheers,

Don

Don's answer sounds good to me.

When the X300s were actually being built Jaguar used several different shocks. I think all were supplied by Bilstein. I suspect that the differences might have been rather subtle in some cases.

As time goes by it's common to 'rationalize' several original choices down to just a couple, neither of which is exact match for any of the originals....but they're close enough.

Cheers
DD

Some years ago when I was rehabilitating the rear suspension bushings, I replaced my nearly 20 year old OEM green colored Bilstein shocks with the Bilstein B6 Heavy Duty after some research.

I have no idea if they are the exact same valving, etc that Jaguar specified for the XJR6 (and I'm sure they likely aren't), but as Doug says I'm sure it is close enough and they were loads cheaper than OEM.