a low moan

Tut · 09-06-2005, 03:57 AM

I've recently hear a low moan coming from the front of my '87 Carerra when I turn the wheel. Can hear it when I turn the wheel as little as 90 degs. I only hear it at low speeds, but that could be a function of too much engine noise at other times. A PPI last November when I purchased the car revealed that the tie rods were shot, so turbo tie rods were installed. Nothing done to the front end since. I did install a steering column bushing recently, but can't imagine that's the cause. The moan doesn't seem that close. The steering seems fine. No binding. Not hard to turn the wheel.

Thoughts?

Thanks.

IROC · IROC's Garage

A "moan" is typically a low-frequency vibration, so what you might be hearing is brake pads groaning at low speeds. I've heard this on my car when pulling away from a stop on occasion.

Moaning noises during turns typically point to wheel bearings, though. Does it happen only when you turn a certain direction? For instance, turning right will load the left front wheel bearings a little higher and cause a "moaning" sound that will disappear as the wheels straighten out. If this is the case, the you can check for excessive wheel bearing play or disassemble the front wheel and visually inspect it.

Does the sound occur only when you're turning the wheel or for the entire duration of the turn? More details about exactly when you hear the sound will make it easier to diagnose.

Mike

JeremyD · JeremyD's Garage

Ahh - That would be a sticking brake caliper...

Tut · 09-06-2005, 05:27 AM

The moaning occurs in either direction, and only when the steering wheel is moving. After I've completed the movement of the wheel, even if the road wheels are still cocked, as opposed to being pointed straight ahead, there is no moan.

JeremyD · JeremyD's Garage

Does it go away if you apply the brakes?

Tut · 09-06-2005, 08:25 AM

Haven't tried that. I'll check that out.

Drago · Drago's Garage

Wheel bearing, no doubt.

goat · goat's Garage

My bet is in IROC's courner.
grab your front wheel at the 12 oclock position and shake any knocking sound then you know for sure.

Tut · 09-07-2005, 03:25 AM

We have a winner! IROC was correct . . . wheel bearings need to be adjusted. Hands a 12 o'clock, push-pull, movement when there shouldn't be any. Hope to have time to do the adjustment tonight. Looked at the Bentley manual. Any other words of wisdom? Hope its only an adjustment, as I'm scheduled to drive to the Glen on Sunday for the vintage races.

Thanks for the help.