[Molarz]

I have a 2010 BMW 335i coupe M sport Xdrive with currently stock suspension

I am wondering whether anyone else has experienced a similar problem when going over a large depression in the road?

It seems as when I go over a fair to decent size depression (not slowing down) that allows for the front suspension to compress.... I often (almost always) here a thud sound in the front end? At first I thought my car was scraping something but it doesnt really sound like a scraping noise? I know we have the transfer case in the front end so suspected something may be contacting it during the compression of the front suspension?

Has anyone ever experienced what I am talking about or know of the problem? If so please chime in and thanks!

[CoralRed335XI]

Originally Posted by Molarz

I have a 2010 BMW 335i coupe M sport Xdrive with currently stock suspension

I am wondering whether anyone else has experienced a similar problem when going over a large depression in the road?

It seems as when I go over a fair to decent size depression (not slowing down) that allows for the front suspension to compress.... I often (almost always) here a thud sound in the front end? At first I thought my car was scraping something but it doesnt really sound like a scraping noise? I know we have the transfer case in the front end so suspected something may be contacting it during the compression of the front suspension?

Has anyone ever experienced what I am talking about or know of the problem? If so please chime in and thanks!

That would happen to me sometimes on my stock xi suspension. I assumed it was the suspension bottoming out and hitting the bump stops. Upgraded to KWs and thump is gone.

[rosica]

Stock xi suspension only has 1" of travel

[NEFARIOUS]

Is there also a rattle? Methinks it also might be the suspension bushing.

[Molarz]

Originally Posted by NEFARIOUS

Is there also a rattle? Methinks it also might be the suspension bushing.

I dont think I have a rattle..... more so just a thud/scratch/scrape sound.

If Rosica says the Xi suspensions only have an inch of travel than it is very likely that perhaps on hard compression that the front suspension is bottoming out early maybe to protect the transfer case?
Crap wondering whether this is going to be a problem since I just ordered my Dinan Stage 1 suspension for the Xdrive but I did get the corresponding bump stop kit so wondering whether I will have better travel in the suspension before it hits the bump stops?

Thanks guys for chiming in

[E93M3-08]

Originally Posted by Molarz

I have a 2010 BMW 335i coupe M sport Xdrive with currently stock suspension

I am wondering whether anyone else has experienced a similar problem when going over a large depression in the road?

It seems as when I go over a fair to decent size depression (not slowing down) that allows for the front suspension to compress.... I often (almost always) here a thud sound in the front end? At first I thought my car was scraping something but it doesnt really sound like a scraping noise? I know we have the transfer case in the front end so suspected something may be contacting it during the compression of the front suspension?

Has anyone ever experienced what I am talking about or know of the problem? If so please chime in and thanks!

Do a Google search for "pothole explosion". You will find that you are not alone.

I had the same issue on my e91 xi although it was more of a BANG!!! than a thud. The car had about 24,000 km on it when I got it and I experienced the problem from day one.

I recently replaced the shocks with a set of Bilstein B6 HD and the problem is completely solved. The ride is firm but not harsh. The car handles way better now too! Couldn't be happier.

[rg87]

I usually only get "thud" sound upon entering/exiting high driveways. Curious to know if this is the same....

[E93M3-08]

Originally Posted by rg87

I usually only get "thud" sound upon entering/exiting high driveways. Curious to know if this is the same....

I doubt it, unless you're approaching the step up (or down) fast enough to bottom out the suspension.

If you're hearing the thud at low speeds over quick changes in road surface height, the situation you mentioned, the noise could be coming from worn anti-roll bar links, worn top hat bearings, loose tie rod ends, thrust arms etc.

Do you feel any vibration in the steering wheel when suddenly applying the brakes at highway speeds?

[Molarz]

I can't imagine that BMW designed this Xi suspension that is arguably much higher than the normal BMW's but bottoms out sooner?? This is going to be fun when my Dinan suspension goes in

[NEFARIOUS]

Ah yes, and it's low enough as it is; even in the xi I find myself having to go through ramps and certain dips at an angle since I know it'll scrape heads on... At the rate I'm going, if I get similar shocks I'd probably have to get a lift mechanism like they do in the Lambo since in a car culture area such as SoCal, I'm surprised that not more is being done to make it friendly to sports-tuned cars.

[Nonecure]

Originally Posted by rosica

Stock xi suspension only has 1" of travel

BS!

I guess when I lowered mine by 2", I must now have a negative 1" travel. There is not a production car in the world with only 1" of travel. I would guess our cars to have around 6" to 8" of travel stock.

[rosica]

Originally Posted by Nonecure

BS!

I guess when I lowered mine by 2", I must now have a negative 1" travel. There is not a production car in the world with only 1" of travel. I would guess our cars to have around 6" to 8" of travel stock.

With stock bump stops travel is 1" you must have removed or cut bump stops.

[stevenh44]

I experience something similar. Just during normal driving, I hit bumps, imperfections in the road or even cracks in the road I hear a thud. the suspension is not even compressing that much because its not a hard bump. Sounds like it's coming from the tires but I put on Michelin NON runflats. Once my rear end goes over I hear same sound just maybe twenty percent of what the front is. The sway bar bushing, is this hard to replace? I'm thinking maybe this may be the cauae

[rg87]

Originally Posted by e9106

I doubt it, unless you're approaching the step up (or down) fast enough to bottom out the suspension.

If you're hearing the thud at low speeds over quick changes in road surface height, the situation you mentioned, the noise could be coming from worn anti-roll bar links, worn top hat bearings, loose tie rod ends, thrust arms etc.

Do you feel any vibration in the steering wheel when suddenly applying the brakes at highway speeds?

No vibrations in the steering w/ brakes at highway speeds. I only hear/feel the "thud" when entering (going up) a high driveway at an angle so the front bumper doesn't scrape.

[rg87]

Originally Posted by CoralRed335XI

That would happen to me sometimes on my stock xi suspension. I assumed it was the suspension bottoming out and hitting the bump stops. Upgraded to KWs and thump is gone.

Which KW's did you upgrade to?

[CoralRed335XI]

Originally Posted by rg87

Which KW's did you upgrade to?

KW V1. Got an extremely good deal too. PM for details.

[E93M3-08]

Originally Posted by rg87

No vibrations in the steering w/ brakes at highway speeds. I only hear/feel the "thud" when entering (going up) a high driveway at an angle so the front bumper doesn't scrape.

Sounds like the anti roll bar end link on one side, or both might be worn.

Worn links are noisiest when driving over uneven surfaces, i.e. one wheel goes over an imperfection while the other wheel doesn't.

[rg87]

Originally Posted by e9106

Sounds like the anti roll bar end link on one side, or both might be worn.

Worn links are noisiest when driving over uneven surfaces, i.e. one wheel goes over an imperfection while the other wheel doesn't.

It's seriously noisy when driving over uneven pavement or cracked roads. At first I thought it was just the horrible RFT tires, but now I'm afraid it's something suspension wise that need replacing.

[rlee134]

Originally Posted by e9106

I doubt it, unless you're approaching the step up (or down) fast enough to bottom out the suspension.

If you're hearing the thud at low speeds over quick changes in road surface height, the situation you mentioned, the noise could be coming from worn anti-roll bar links, worn top hat bearings, loose tie rod ends, thrust arms etc.

Do you feel any vibration in the steering wheel when suddenly applying the brakes at highway speeds?

THIS is exactly what i have been experiencing and trying to diagnose -- i have a new set of sway bar end links (are these the same as roll bar end links?) but when i looked at them they werent loose..

but i definitely get some wheel vibration when braking at high speeds and the thud coming out of the driveway. what do you suggest i check first? thanks

[Molarz]

OK this is sort of reviving my current post but driving my car alot today and going over depressions in the road at decent speeds (that somewhat compress the front end)..... I definitely hear more like a SCRAPE/clunk noise. It happens so often that I can't really believe that it is my suspension bottoming out that frequently.

Im wondering whether whether it is sway bar end links or sway bar end bushings? Someone here mentioned the strut tower hat bushing and Iguess it could be that as well?

However, the most notable sound seems to be a definitive SCRAPE or something but my car is so high off the ground I cant see this happening anywhere on the car?

Any other opinions? Thanks

[AWD Addict]

Sounds like a front end issue like a thrust arm bushing. Could also be a blown strut.

[Molarz]

Originally Posted by AWD Addict

Sounds like a front end issue like a thrust arm bushing. Could also be a blown strut.

How would I know if it is a blown strut? Any other symptoms to look for indicating something is wrong with my front struts since I need to reuse these struts for my Dinan stg 1 suspension?