A 'shocking' State

Titch LS · January 17, 2016

A good while back I had new steering rack bushes fitted to cure a jolt I could feel in the steering column when driving over bumps. The new bushes worked a treat at ironing out the jolt. Also at that time, for some reason, I opted for new shock absorbers on the front as well, (due to highish miles and my obvious ignorance of Lexus' quality)..... I bought some KYB's (OEM) replacements and they were great so long as the road was billiard table smooth. However, on an uneven road it was as though you could feel an ant through the steering wheel, the ride became that sensitive to bumps and thumps. Over time I was getting more and more fed up with it . What to do? Was it the shocks? No. It turns out that each coil spring top nut (the single one on the shock absorber piston rod) had been overtightened by the garage when they fitted the new shocks. With all the weight of the car on its wheels, I re-torqued that nut to factory spec (28 Nm) and that changed the ride back to what I remember it was like when I first bought the car. Far more Lexus-like. I was surprised that such a small adjustment could make such a difference. So, if you ever get around to changing your shocks, don't always blame them if the ride quality ends up not so good. It could be the wrong pre-load on your coil springs that's the problem.

steve2006 · January 17, 2016

You wouldn't think it would make such a difference but there you go, how did you discover this was the cause...new torque wrench for Christmas :) or a second opinion.

Beejay55 · January 17, 2016

So, I am not the only one who wanted a torque wrench for Christmas. I didn't get one

steve2006 · January 17, 2016

A torque wrench is not just for Christmas :)

Spacewagon52 · January 17, 2016

I have a torque wrench but......................... I do not know how to use it! We live in a crazy world!

Well done for finding that information on the shock absorber - that will be filed away on my computer - as the brain does not work as well these days.

Titch LS · January 17, 2016

Steve, the drop in ride quality was very un-Lexus and bugged me for ages. I was actually replacing the shocks myself but one of the bottom bolts was completely seized solid and I couldn't break it free, so it was off to my friendly garage. They ground it off eventually and fitted the shocks for me. Recently it occured to me that when they fitted the coil springs back on to the new shock absorbers they might have overtightened the top nut by using air tools to save time. I saw another garage do this once, years ago, on my Rover. This compresses the springs a bit too much and at the same time has the effect of forcing up the top mounts too hard against the bottom of the turret in the engine bay. This results in road vibrations being transferred through the car and not dampened sufficiently by the suspension. Backing it off and using of a small torque wrench sorted it.