Ok, after my spat with Skoda UK about the hard suspension on my L&K Estate I'm looking to replace springs and shocks with the popular Eibach / Koni FSD combination. Looking at the Koni website I seem to have three choices of model number for the FSD shocks - either 4015 for original strut at 50mm, 4016 for a 55mm front strut, or 4090 for RS suspension.

Given I'm going for the Eibach springs which lower by ~30mm, do I need the RS spec 4090 shocks? If not then how do I find if I need the 50mm or 55mm spec? Is this the diameter of the shocks in place at the mo or of what they attach to? (Numpty question I know, but thought I'd ask here first before I go asking my mechanic idiotic questions... )

Thanks in advance for any help.

Which engine is in your L&K? This will define whether you have the 50 or 55mm strut size. Also, check the sticker on the passenger door slam panel, which will list the axle load weights and report back with those.

The 4090 model is the one to go for, as these are the newer, revised FSD model. I have these on my PD140 Elegance and they're spot on.

If these hadn't been available I would have gone for the Bilstein B12 setup instead, as there were too many instances of the earlier FSD models going soft and leaking.

It's the 1.8TSi, axle weight from the passenger door sticker is 1050kg.

Thanks for the help, I didn't even know the sticker existed and was trying to figure out where to find the axle weight...

No probs. It's a useful sticker. Took me a while to find it as well

With the 1.8 that's a bit trickier I'm afraid, as I don't know anyone using 4090s with that engine. The loading for my PD140 and the vRS (both petrol and diesel) is 1100Kg you see. It might have to be a question to Koni.

Also about the estate application too, as loadings for the rear might well be different too?

Alternatively, a decent Koni agent like Awesome or JKM might be able to provide you with more info.

As for the strut diameter - I'd be confident that they'll be 55mm. I'll try to find some more info to back that up

Thanks for that Wardy, really useful. I think that the Estate spec shouldn't be a problem as the Koni website has the 4090 model for VRs hatch and estate so I'm guessing it's more to do with the lower springs but I'll check with one of the Koni agents to see what they think.

Cheers!

OK, just wasn't sure if the estate layout meant a slightly different rear damper design would be required.

Might well just be a case of getting the right loading for the springs then