jeeper31

Help all. I hear a thunping noise which I think is coming from the front. It seems to get faster when I pick up speed and is more of a slow shhh when just rolling. I checked all tires and they look good. Hard to tell where it is coming from however, I don't hear it when going in reverse so i am assuming it is from the front. I hear is when car is in gear or out of gear and just rolling.

Any ideas? Please help. All is appreciated.

DanD

I'd check for something in the tires. bolt or nail. A bolt will make a loud noise as you roll over it. Shsh as it leaks air. Check air pressure, if one's low, that may be the one.

jeeper31

The shhh is more of a scraping noise until the car speeds up and then it becomes a thump.

Danno

Run over any squirrel lately? They tend to stick to the tires and go thump, thump each time. Bigger cats and dogs are too heavy to stick.

Check the brake-rotors and pads. Then the wheel bearings. When in doubt, pull the engine...

jeeper31

What am I looking for?

MPD47

Well usually a thick bit of fur with some blood is a good indication of what to look for Sorry i couldnt resist.

Hans

Anything static (like shields, brake pads, btrake lines etc) touching anything rotating (like rotors, wheel)
Check the rotor edges for corrosion, if there, scrape it off.
Also check the brake pad thickness, if thin the lip on the rotor will touch the steel backing plate of the pad.
Lift car till wheels are free, helps a lot.
Tn case you have lock nuts on the wheels, then mark the position on the wheel AND THE HUB.
The lock nut weight differs from the standard, if you move it there is a fair chance you develop a balance problem.
TakeCare

Porsche-O-Phile

Dead babies are the worst - they tend to stick in the wheel wells and splatter where it's hard to pressure-wash 'em out.

(Yup, it's officially a race to the bottom)

Greg86andahalf

Babies-

Don't get me started.

I couldn't sleep the other night. Neighbor's screaming baby was keeping me up. Finally I went outside and shut the lid on the dumpster!

It a JOKE!!!

jeeper31

Love all the baby and squirrel jokes but now back on topic. I think the noise might be coming from the rear. Any suggestions?

MPD47

CV joints if it's in the rear. Definitly.

jeeper31

ok. this might be a stupid question. Is it ok/dangerous to put rear of car on jacks and start car and get the wheels moving to hear if the noise is coming from the rear?

Luis de Prat

Sounds like Ferris Bueller's ill fated way of trying to roll back the miles on his pal's dad's Ferrari replica...

Seriously, this sounds like your front wheel bearings may be suspect. Do you have a Hayne's manual? Checking/replacing them is pretty well explained there. Available at your local generic-chain Auto parts store (Autozone, Pep Boys, etc.)

Or, check here in the Garage Manual section: Clark's Super-Helpful-Where-Would-I-Be-Without-It Garage

jeeper31

I am having difficulty figuring out if noise is coming from front or rear. Just as i decide it is from the front it sounds like the rear and vice versa.

Luis de Prat

Yep. Wheel bearings. Try coasting with the car out of gear and weaving left and right, preferably down hill.

If the noise increases while putting the load on one side, that's probably where your problem is. With the early 944s like yours, the rear wheel bearings are considerably easier to replace than with post 85.5

BTW, don't do the weaving test drive right after having some brews with your buddies.

P.S. Running the car on stands wouldn't help you detect the bad bearings because it's only produced under load. You can, however, try turning the wheels with the car in the air. Also, any wobble/play in the wheel is a pretty sure sign of bad bearings.