[Andy198712]

Hi,

2010 325d E91 RWD 150k miles
Recent PS4/5 tyres and balance.
Reasonably recent shocks and suspension overhaul.

This first happened on a long drive at cruise control 70mph. Felt like I drove over very rough tarmac or rumble strips and slowly increased.
I slowed to about 50 and it slowly went away then stayed away for the rest of the 200 mile trip.

A month later (had only done shorter trips in the mean time)
Did 240 mile drive last night, no issues
Came back today. Same drive same speeds 70mph
I got this vibration about 3 times.

Again, feels like rumble strips I can feel it in the car and the seat.

It’s an auto, knocked it into N and no change. Tried speeding up and slowing down and it just changed the vibration. Slowed to about 50 and it faded away

Then back up to 70 and all good for about an hour till it did it again.

Accelerates fine.
Not engine dependant.
Doesn’t seem to be brakes.


Does this sound like the centre bearing starting to go? And getting some resonance going on and getting worse till I drop enough speed to stop it and then it smoothes out?
Or more the rubber flex disc?

Cheers
Andy

[Andy198712]

Had a look under the car today, checked front and rear rubber flexis and the centre bearing, gearbox mounts and suspension parts

The rear flex has cracks in it which is going to be my first thing to change as the rest looked okay, front flex looked good, couldn’t feel play in the centre bearing or the UJ’s
I could deflect the rubber in the centre bearing a very small amount but I espected this as it’s rubber.

Here a pic,

[Andy198712]

And yes my diff input seal does weep but not enough to cause a drip yet, level has always been okay

[Andy198712]

Something I noticed after cleaning the car was my rear right wheel had more brake dust.

After a short drive I could touch my left hand disc but my rear right disc was too hot to touch! So seems it’s a sticking caliper.
Going to check the pins first and if it’s not those I’ll do a re man caliper

[bmwbob89]

Definitely figure out that brake problem first. Probably a bad caliper.

[Andy198712]

Originally Posted by bmwbob89

Definitely figure out that brake problem first. Probably a bad caliper.

Yeah deffo a smoking gun, going to check the pins tonight and probably just order a reman caliper if it’s not that, as even a rebuild kit and new piston won’t help if the caliper has some corrosion in it I guess.

And less down time of the car I guess. Will see how it looks

[Andy198712]

So stripped it down.

Pins seemed good, not hard brake dust ect.

Wound the caliper back in with a G clamp and it wasn’t much effort but maybe a little.

The rubber boot around the piston seemed a little crusty and a quick peek under from the piston end showed a bit of corrosion dirt in there. The end of the boot that’s seals to the caliper was bumpy and stuck down with rust.

So cleaned up the pins and carrier ect, ceramic brake grease on the pins and moving points and exercises the caliper a good few times and seemed okay.

Going to try a test drive but I reckon I’ll get a pair of rear remanufactured calipers as I doubt the other side will be much better

[Andy198712]

Also pads are a bit worn, not on the sensor yet but about 7mm left so I’ll put new pads in, the ATE discs are still good, no lip ect so probably just do the pads this time

I noticed the pads say BMW TEXTAR so if your looking for an OEM make then there you go