Rough ride on concrete motorway?

[Mothman]

Whilst driving on a tarmac motorway a week ago I heard a loud bang and it felt like something had hit the underside of the car, but as I didn't see anything in the rear view mirror bouncing down the road and the car continued to drive fine I thought nothing more of it and just assumed I must have run over something.

It may not be connected to the above but I had to take the wife & her friend to Gatwick last night and on the concrete sections of the M25 the ride was bumpy, noisy (seemed to be coming from the rear) and generally unpleasant to drive. I know concrete motorways are always a pain because of the way they are laid in sections this was far worse than I have previously experienced. As soon as we hit a tarmac section the ride would return to normal. Have shone a torch up at the rear springs and though difficult to fully check I can't see any obvious signs of a break and the dampers show no sign of leaks.

I cant see the front springs to check because of the undertray but is there anything else I should be checking for?

[marinabrian]

Originally Posted by Mothman

Whilst driving on a tarmac motorway a week ago I heard a loud bang and it felt like something had hit the underside of the car, but as I didn't see anything in the rear view mirror bouncing down the road and the car continued to drive fine I thought nothing more of it and just assumed I must have run over something.

It may not be connected to the above but I had to take the wife & her friend to Gatwick last night and on the concrete sections of the M25 the ride was bumpy, noisy (seemed to be coming from the rear) and generally unpleasant to drive. I know concrete motorways are always a pain because of the way they are laid in sections this was far worse than I have previously experienced. As soon as we hit a tarmac section the ride would return to normal. Have shone a torch up at the rear springs and though difficult to fully check I can't see any obvious signs of a break and the dampers show no sign of leaks.

I cant see the front springs to check because of the undertray but is there anything else I should be checking for?

Rear spring sounds a possibility, however having said that concrete roads are like driving on a piece of Ryvita

You can check the front springs without removing the undertray though

[Mickyboy]

Rear springs are often difficult to detect when they break, as most of the time it’s at the bottom of the spring on the end, by the spring isolator, removal of the wheel makes it much easier to see.
Mick

[Teflon]

Originally Posted by Mothman

................. on the concrete sections of the M25 the ride was bumpy, noisy (seemed to be coming from the rear) and generally unpleasant to drive. I know concrete motorways are always a pain because of the way they are laid in sections this was far worse than I have previously experienced. As soon as we hit a tarmac section the ride would return to normal.................

I live quite close by to that section of motorway, and hate it with a passion . It makes no difference what car we happen to be driving, the ride is always noisy and uncomfortable over the concrete parts - even by concrete road standards it's bad. I honestly believe the roads would have been smoother back in Roman days.

I doubt there's anything wrong with your car, it's almost certainly just the poor quality of that particular road surface.

Cliff

[stevestrat]

The first section of concrete I came across was a few years ago on the A1 south of Dunbar. It was (and still is) hellish, like driving on a washboard.

[Billyuk1]

Worse motorway for me is just past elsmere port. It always sounds like running on a flat tyre. Lucky I only go that way one a year.

[jackatesme]

There is a section of the A40 between Abergavenny and Raglan about 3mls. as you say very noisy, but i can't remember there being any repairs needed to be done in the 30 odd years it's been there.

[rockerbox]

Having heard a "bang" and then seeing these problems, the first thing to look at would. to me, be the rear springs. You have to get your hand in there and follow the coil down to the end, the pigs tail, as it joins the lower cup. You will find a break if you're dilligent (presuming one exists ! ).
My MOT man whom I've used for years employed a fresh faced tester who found both mine were broken, didn't notice any ride difference myself, but "that's because they've been broken for years" he said. Yep, apparently many cases of this go through MOT even without being noticed.
Have a good check yourself or ask your mechanic to be sure.
HTH, very recent problem I've had myself.

[willshot]

The A180 between Barnetby and Grimsby is horrendous.

[victorgte]

When the final section of the M42 was completed it was a shocking motorway. So bad there was a campaign to have it relaid in tarmac rather than concrete.
Instead without notice there was a skimming of the surface to give it a smoother ride. Eventually it was redone as tarmac but many years later.
I can’t see how any concrete motorway can be as safe as a tarmac surface.