Two weeks ago I got shunted in the rear by another driver whilst I waited to enter a roundabout.

It was a fair old whack but the only visible damage was a slightly crumpled bumper (the other car, Skoda Citigo, looked untouched).

Drove 2 miles back home and during that time passengers at the back commented they could hear a droning noise from underneath them they didn't recall before.

So, tell the insurance company about the incident etc and they recover the vehicle to a repair shop via a lo-loader (thankfully other party had insurance so no cost incurred on my part).

The repair shop inspect and supposedly road-test the car and they diagnosed that all that was wrong was the bumper - which was duly repaired and I picked the car up today.

Driving 20 miles home just now, the car feels normal - no vibration etc.  But that droning sound can be heard - not loud, but definitely noticeable especially at above 40mph; pretty imperceptible below 30mph. 

Going to tackle the insurance company about getting another inspection done on the car but interested to hear opinions on what it could be.

Note, I'm one of the Sach's clutch victims so the Gearbox & Clutch was replaced in 2016 and the Dual Mass Flywheel in Nov 2017.  Car now on 61000 miles.

At a guess I'd say some heat-shielding has been knocked a bit loose underneath. I'd get in underneath and check all the fasteners on the exhaust heatshield as a first step. Those fasteners are a little spring type clip that pushes on over a threaded shaft: they push into place but can be unscrewed to remove them. I'd hazard a guess that the shunt you got made some of them pop down and leave the heatshield a bit loose.

Could the alignment have been knocked out rear wheels?

Surely something has to give when hit from behind by another car? 

 

57 minutes ago, gav_is_con said:

Could the alignment have been knocked out rear wheels?

Surely something has to give when hit from behind by another car? 

 

Not necessarily. There's a lot of thought put into the crash structures at both ends so that the important bits underneath don't suffer in a minor tip like this.

Our this could all be coincidence and you have a wheel bearing on its way out. 

 

Is the noise there when you are stationary and rev the car in neutral? Possibly something to do with the exhaust ( something loose and resonating )

 

Other than anything obvious hanging off, something to do with the rotation of the wheel is a likely bet.

 

 

13 hours ago, Shaunieboy said:

Our this could all be coincidence and you have a wheel bearing on its way out. 

 

Is the noise there when you are stationary and rev the car in neutral? Possibly something to do with the exhaust ( something loose and resonating )

 

Other than anything obvious hanging off, something to do with the rotation of the wheel is a likely bet.

 

 

Many thanks to everyone for their quick replies - this forum is really helpful.

I checked the heatshield this morning and its solid as far as I can tell.

Driving this morning I am leaning towards there being an issue with the wheel bearing - turning the car towards the right definitely makes the drone quieter.

Insurance company not being co-operative and refusing to do another inspection so I've got the car in for an inspection with my local garage tomorrow - going by them, failing wheel bearings is a common fault that they see in VAG cars.

If it's the wheel bearing it's going to be fun trying to get that linked to the shunt.

How long should the bearings last anyway and should they be replaced in pairs?

 

3 hours ago, Donbrig said:

Many thanks to everyone for their quick replies - this forum is really helpful.

I checked the heatshield this morning and its solid as far as I can tell.

Driving this morning I am leaning towards there being an issue with the wheel bearing - turning the car towards the right definitely makes the drone quieter.

Insurance company not being co-operative and refusing to do another inspection so I've got the car in for an inspection with my local garage tomorrow - going by them, failing wheel bearings is a common fault that they see in VAG cars.

If it's the wheel bearing it's going to be fun trying to get that linked to the shunt.

How long should the bearings last anyway and should they be replaced in pairs?

 

Yeah generally in pairs unless there has been a knock to a single wheel which has damaged the bearing and the mileage is low.

 

My superb is on 110k and still on original bearings, my old golf had them all done around 100k - 120k.

 

I wouldn't replace both if the car had only done 20k for example.

Well, garage came back and they have diagnosed that a faulty rear wheel bearing is making the noise. 

Also found the front brakes need replacing which doesn't surprise me going by the MOT advisory earlier this year which mentioned the discs were badly scored (mind you, pretty poor that the front brakes are needing replacing after just over 20k miles/25months).

When asked about replacing the bearings in pairs the garage said there was no need. 

Their view was to wait until there was an issue with the other bearing as replacing now gave no real cost benefit as they didn't get any part discount for buying two hubs instead of one and it would take basically the same amount of labour time to replace the other bearing.

Get the car back on Monday so we'll see if things are all okay when I give it a drive.

Really get feeling this machine is jinxed going by the amount of mechanical issues there have been over the last few years!

 

15 hours ago, Donbrig said:

Also found the front brakes need replacing which doesn't surprise me going by the MOT advisory earlier this year which mentioned the discs were badly scored (mind you, pretty poor that the front brakes are needing replacing after just over 20k miles/25months).

When asked about replacing the bearings in pairs the garage said there was no need. 

Their view was to wait until there was an issue with the other bearing as replacing now gave no real cost benefit as they didn't get any part discount for buying two hubs instead of one and it would take basically the same amount of labour time to replace the other bearing.

Regarding the break disc wear: You should look at your driving style. My pads and discs have never been replaced since new, and the ODO is at almost 100.000 km (60.000 miles). Wear is still only minimal. They can easily double this number.

Regarding the bearings replacement: Your garage gave you a bad advice. Replacing two hubs will only take about 50% more time, since many things only have to be done once (driving the car onto the bridge, raising it, finding the right tools, storing the tools, cleaning up, making the bill etc, paying for the loaner car). And it saves you one more trip to the garage.