Car shaking

nails1

I got a reconditioned Abs unit in my car a month ago after my original part failed. A couple of times since then I have noticed my car shaking on the motorway at certain speed ~50 mph. It would shake or vibrate for a minute or two then stop. It doesn’t always happen just sometimes. Mechanic said that because Abs was inactive for so long (around 12 months) that problems involving the brake system may have developed that wouldn’t be noticed with an inactive Abs unit. Is that possible? Car is 2006 bmw 525i.

Alanstrainor

Check the basics first. Are your wheel nuts tight? Check your tyre pressures all around. It could be something simple like your wheels needing to be balanced, perhaps a weight was knocked off? There are more possibilities here though.

As for your mechanics excuse. Nonsense. If you're travelling at 50 and not braking then the ABS unit, nor your brakes are doing anything.

biko

If it only a couple times in a month then it's not purely the tyres or it would happen all the time.
You need to troubleshoot more, but start with the above suggestions.

elbyrneo

biko wrote: »

If it only a couple times in a month then it's not purely the tyres or it would happen all the time.
You need to troubleshoot more, but start with the above suggestions.

Had very same problem and wheel alignments sorted it for me.

rizzee

Flywheel?

Cee-Jay-Cee

nails1 wrote: »

I got a reconditioned Abs unit in my car a month ago after my original part failed. A couple of times since then I have noticed my car shaking on the motorway at certain speed ~50 mph. It would shake or vibrate for a minute or two then stop. It doesn’t always happen just sometimes. Mechanic said that because Abs was inactive for so long (around 12 months) that problems involving the brake system may have developed that wouldn’t be noticed with an inactive Abs unit. Is that possible? Car is 2006 bmw 525i.

That mechanic speak for 'I haven't a clue what wrong with it' Did he put the car on a lift and check the wheels, suspension, brakes etc or did he simply offer that little nugget of useless information?

Before doing anything else I would check that all front wheel nuts are tight.
After that you need to get the car up on a 2 post lift with the wheels off the ground and check steering joints and ball joints etc as It could be any one of a number of different things.

biko

elbyrneo wrote: »

Had very same problem and wheel alignments sorted it for me.

The car would shale only very occasionally like twice in a month?

50 mph is 80 kph. Classic tyre shake is at 110 kph or thereabouts