That is a very good point, retgwte, and I didn't mean to be overly critical of the Myvi's seemingly light build. I didn't have to adjust the rear-view mirror; it was fine as is, as luck would have it. So it could have been 'wrong' from the off.

However, over poor surfaces not quite a rattle, more a resonance, could be heard (felt?) from the Myvi's tail-gate area: totally absent in the Sirion, which I have since driven.

I'll post further comparisons and contrasts, later.

AF.

Careful! What the towbar supplier really means is "has the car got a canbus/multiplex wiring system", which I'm pretty sure your car has!

If so, then you cannot simply wire in the old fashioned towbar electrics into the lights like the good old days. Modern wiring systems like those I refer to above carry the main power down one wire and very low voltage signals in the light wiring to tell which light to switch on. There isn't enough power to light the towbar electrics from these wires. Plus, if you start tampering with the wires you risk the computer getting confused thinking that tail bulbs have blown. It may then start compensating by lighting the brake lights at low voltage to emulate the taillight, for example. In short, it won't work!

There's two options, either you can fit a bypass relay that powers straight from the car battery and gets a signal from the lights as to when to activate without messing them up, or you can buy a vehicle specific wiring kit that usually plugs straight into the rear fusebox and often requires activation from a dealer.

Guess which of the two is more expensive!

If in doubt, ask a Ford dealer and then buy the right electrics from your towbar supplier.

This explains it better than me:

www.towsure.com/bespoke/wiring_chooser.html

It's possible the wheels need balancing again. If not, there may be a tracking problem. But I would think the balance of one or both front wheels may be a bit out.

A badly out-of-balance rear wheel can also cause vibration, but it won't come through the steering wheel.

M25 this morning:
I looked over to my left and there was a woman in a brand new BMW doing 75Mph
With her face up next to her rear view mirror putting on her eyeliner.
I just looked away for a couple seconds !
And when I looked back she was halfway over in my lane, still working on that makeup.
As a man, I don't scare easily..

But she scared me so much; I dropped my electric shaver,
Which knocked the meat pie out of my other hand.
In all the confusion of trying to straighten out the car using my knees against the steering wheel,
It knocked my mobile phone away from my ear which fell into the coffee between my legs, splashing, and burned big Jim and the twins, ruined the phone, soaked my trousers, and...............disconnected an important call.

Both my sons have found that if you are a younger driver having dad named on the insurance gets you a reduction even, in one case if he's 120 miles away.