While driving over a bumpy road I hear a rumbling sound somewhere in the center of the engine compartment. I visited the dealer 5 time and they claim it is the brake system and I just have to live with it. Strange thing is however that at low speed and turning the steering wheel also cracking sound appears. I believe its some how related. What could be the problem? Thank you in advance. Adrian

You need to have all the suspension components checked for excessive wear. Also check the wheel bearing for noise.

Suspension needs to be checked !ball joints ,shocks,struts ,tie rod ends and be she's.

it rumbles as you are about to stop, well that depends.

if there is a vibration AS you are applying the brakes, and about to reach a stop, it could be that your brake rotors need machining, or "turned"; however, in this case, you would also hear a grinding, as well as feel the grinding through your foot.

there is also a "rumbling" associated with a strut mount gone bad; however, this is more of an audible clanking, and is also audible when driving slow on a bumpy road, and not really specifically in the process of stopping.

for either of these, please stop using your radio, and possibly open the windows, to better describe the sound.

IF the car shakes when sitting at a stoplight, or such, please watch your rpm gauge (tachometer), and see if the idle speed is exceptionally low or erratic.

if this is the case, it may be that your throttle positioning sensor, mass airflow sensor, or the like, is malfunctioning, and is giving a warm engine a fuel/air mix appropriate for a cold engine.

Sounds like a half shaft. Reach around behind each wheel and see if there is play in the shaft that leads from the wheel to the transmission. There should be no play. Other possibility is a bearing hub. Jack up car, grab the tire at 9 and 3 o'clock. Shake wheel if there is movement not from the tie rod then it is the bearing hub.

look at the front lower engine mount. I had similar noise which has been driving me nuts, thought may be thesway bar links, put it on friends hoist and saw that the front engine mount (mounted to bottom of lower radiator support) was cracked and the rubber bushing inside very worn with pieces missing. odd thing is that reving, or putting into gear never caused it to make a noise, just certain bumps. I ordered part from Autozone,hopefully it gets here before the holiday week end is over.
Good luck

look in the side compartments and see if there is a bottle moving around somewhere also any storage compartments in your vehicle

Check engine mounting rubbers or bushes. If worn or loose they can cause noises like this. Shouldn't happen in an 08 though. Check things like the battery strap is tied down and the fuse box cover is secured.

what kind of noise> check your oil first

Does it happen when you accelerate and decelerate? If so, it might be a motor mount or transmission mount. If it only happens on bumpy roads, check to see of the battery is held down tight, otherwise I'm at a loss.

the problem with your truck is your knuckle bearings. I just replaced them on a friends truck and it sounds like the same problem. Just look on the inside of the front hub close to where the front axel attaches to the hub. If the seal is gone you will have a ring inside the hub on the axel shaft.