Thumping noise & vibration coming from the front

[LuckyTaxi]

It just happened yesterday and it's annoying the hell out of me. When accelerating at low speed (30-40mph), i can hear and feel a thumping noise coming from beneath my feet. It's so obvious when I'm slowing down into a turn but not so much when I'm going above 50mph on the freeway. The steering wheel DOES NOT shake so I don't think it's the rotors or alignment. COuld it be the brake pads? If so, why would I hear it at low speed when I'm NOT braking?

 

[Bignate603]

What vehicle is this?

Does it only happen when you step on the gas after idling? Like if you took your foot on the gas and stepped on it again would it thump? The reason I ask is because I had a friend who's transmission somehow worked itself loose, the bolts allowed just a little bit of play because they had backed out a turn or two but didn't fall out. He would step on the gas and the engine would twist a little under load making the transmission thump against the body. Cruising it was fine.

Also, does it only happen in that speed range? If it only happens from 30-40 mph that screams transmission problem, most others wouldn't be so speed dependent.

 

[LuckyTaxi]

Ah crap, damnit hope it's not the transmission! It's a 02 lexus is300, the car shirts perfectly, no issue whatsoever.

I hear it regardless if I step on the gas or not. If i take my foot off and let the car cruise by itself, I feel/hear it beneath me. My gf thinks I'm nuts but she wouldn't know what to listen for anyways.
Once it goes over 50mph or so, the noise goes away. It's so obvious when coming to a turn or a bend with or w/o me stepping on the brakes BUT if I do apply the brakes, the noise is much more obvious.

 

[rdp6]

I had noise at low speeds, which was distinct 'lump lump lump' noise around 35mph around 30K on my Passat. New tires fixed the noise.

OT: I expected the OEM Continentals to last 40K, but tread was looking pretty low. I drive 90% highway, 60+mph. Are highway speed miles that much harder on tires than low speed miles? The roads I drive on are in pretty good shape (for N. Ohio, that is).

 

[LuckyTaxi]

Originally posted by: rdp6
I had noise at low speeds, which was distinct 'lump lump lump' noise around 35mph around 30K on my Passat. New tires fixed the noise.

OT: I expected the OEM Continentals to last 40K, but tread was looking pretty low. I drive 90% highway, 60+mph. Are highway speed miles that much harder on tires than low speed miles? The roads I drive on are in pretty good shape (for N. Ohio, that is).

Tires I have on the front are pretty new (< 1 yr). I'm hoping it's the rotors/brakes and not the transmission. Regardless, I'm taking it to the stealer to see what they say.

 

[bruceb]

If it is a front wheel drive car, I would suspect a bad axle half shaft or cv joint. Rear wheel drive could be play in the driveshaft of rear end gears.
It can also something as simple, but not always easy to change, as either a motor or transmission mount. And check the front struts bearing mount
plates at the top of the struts. When they are bad, it will clunk. Had this happen on my Pontiac.

 

[alkemyst]

also check the motor / trans mounts...make sure nothing broke or is loose.

 

[f1r3s1d3]

Originally posted by: bruceb
If it is a front wheel drive car, I would suspect a bad axle half shaft or cv joint. Rear wheel drive could be play in the driveshaft of rear end gears.
It can also something as simple, but not always easy to change, as either a motor or transmission mount. And check the front struts bearing mount
plates at the top of the struts. When they are bad, it will clunk. Had this happen on my Pontiac.

.

 

[bruceb]

f1 .. What was the point of just quoting what I posted without adding a comment or suggestion ?

 

[potato28]

Originally posted by: bruceb
f1 .. What was the point of just quoting what I posted without adding a comment or suggestion ?

I think it might be his way of QFT, which I also agree with you on.

 

[Bignate603]

Originally posted by: potato28

Originally posted by: bruceb
f1 .. What was the point of just quoting what I posted without adding a comment or suggestion ?

I think it might be his way of QFT, which I also agree with you on.

Yup, sounds like good advice.

 

[bruceb]

No offense meant or taken ... let's see what the OP finds after he gets it repaired.

 

[LuckyTaxi]

initial reports say it could be a bad strut. they are going to have another mechanic test drive it to see if they can get to the bottom of it.

 

[Blunc]

for gods sake, let the cat out of the glove box.