540i: Bone-jarring ride

[RSK540iA]

Every since buying my E34 540i last year I've had to live with a hard and uncomfortable ride. The control arms and shocks have been replaced. Last month I replaced the tyres. I've now dropped the tyre pressures to 2.1/2.2... not much improvement. Any ideas? Thanks!

[Macv]

Springs? Bumpstops?

Give us some specs on things. Is it basically stock? Lowered suspension?

[BMWDriver]

What wheels are on ? Low profiles are absolutely rougher than 15 or 16 inch wheels.

[CharlesAFerg]

I've got a stiff setup with my springs, shocks and polyeurathane everything, replaced al the arms and links... etc
I'd hardly call it bone jarring, you must have destroyed bump stops, it made a nice bang in my old stock trash.

They were 1/3rd of the original length, lol - terrible.

[Rick L]

I couldn't feel the difference in ride comfort between 15" to 17" when I upgraded. But once I upgraded the suspension with Koni sports adjustable and Ebach springs then I noticed all the imperfections of the roads. I have my Koni at half turn. I prefer stiffer ride.

What wheels are on ? Low profiles are absolutely rougher than 15 or 16 inch wheels.

[RSK540iA]

Thanks guys!

The suspension is stock standard, as are the rims (alloy) and tyres (Bridgestone 225/60 x VR15 ER300). I just fitted Sachs touring shocks to the front, the bump stops are apparently inside the shocks so they're brand new. The ride height is also good. I suspect PU bushes were fitted when the control arm bushes were replaced. They absorb very little, if anything at all. Every little undulation is transferred directly to the chassis. My 1985 MB 230E gives me a better ride.

I spoke to another E34 540i owner yesterday. His ride is silky smooth.

[CharlesAFerg]

bumpstops in the front shocks...? What? Not on my E34, but a touring I wouldn't know.

I couldn't feel the difference in ride comfort between 15" to 17" when I upgraded. But once I upgraded the suspension with Koni sports adjustable and Ebach springs then I noticed all the imperfections of the roads. I have my Koni at half turn. I prefer stiffer ride.

I totally noticed a difference with my style-5s, I'm surprised you didn't.

[Tiger]

I had same problem as you... until I changed the sway bar links and then everything is silky smooth again.

[Rick L]

Maybe the difference in tires? I have Falken Azenis on BMW 17" BBS 42 with 235 (at 34 psi) fronts and 255 (at 38 psi) rears. Even with wider 255 rears, I couldn't really noticed the difference in ride comfort (from stock 15" 225). But definitely noticed the difference in performance wise.

I totally noticed a difference with my style-5s, I'm surprised you didn't.

[RSK540iA]

Sway bar, would that be the same as 'anti-roll' or 'stabilizer' bar? The car's going in on Tuesday, I'll ask them to check every single front suspension component and give me a full report.