k20z1

hey all. my parents have a 2000 3.2tl nav. the car has approx. 119k on it now, and the transmission was replaced under the warranty extension at ~99k. right now, the car seems to make noisy rattling/gear buzzing type noise usually associated with a bad differential. the sound is definitely directly connected with the vehicle speed, NOT engine speed or gear changes. usually around 35-40mph it gets audible and gets louder as you speed up.

i did a search, and came up with another person posting up similar complaint as mine. there was a few responses about it being a possible wheel bearing. although, i have a little hard time believing it's a wheel bearing because the noise isn't a wobbly woosh'ing sound usually connected with a wheel bearing. also, there was no response by the threadstarter in regards to what fixed his issue.

i just thought i'd get some insight because i didn't want to go the dealer and end up paying an arm and leg for diag time. i was curious if there was anyone here that could post a possible relation to this problem or has experienced it before themselves.

Kmizzal00TL

I have the same car with the same noise. It's definitely speed related. Once I hit 55-60 mph the buzzing begins from the front drivers side, in the vicinity of the tranny. It's not the tires or the wheel bearings (both are new). Through a lengthy process of elimination, I'm convinced it's the differential bearings.

Has anyone else experienced having a bad differential in a 2 gen TL? If so, what were the symptoms/noises? I would hate to spend the bread on having it replaced and it not be the problem, but I'm at the point of just doing it and hope for the best. I started hearing it roughly 4 months ago, and now it's becoming unbearable.

01tl4tl

welcome to the forum Our TL wheel bearings make a whine not a whoosh as they fail

Have you used a mechanics stethoscope to locate the noise
that will usually pinpoint it very quickly
Dealer is NOT the place for a noise diagnosis- 1.5 hours charge @ $100-140 per hour! and hope the oldest tech there has seen it once in his lifetime to know what is happening.

A private owner- not big corp store- trans shop can put the car on a lift and use the stethoscope to ck things out

Put aside what you have a hard to believing and get the car looked at,
Wheel bearings are a common problem, a diff failure = nearly unheard of!

Chojun

Just thinking out loud but a failing differential might have other symptoms than noise. Check for leaks under your transmission/axle. The c/v axle has very specific clearances with the differential. Is your alignment off? Also, check the heat/dust shield around the rotors, I've heard people having grinding noises when it ended up being a bent shield.

I'm willing to bet it's your wheel bearings that are the problem. Mine are bad (front driver is bad, front passenger is going bad). Here are my symptoms:

My wheels will predictably make a speed-related grinding noise when I get above certain speeds - around 50mph. The noise typically appears when going around bends on the freeway (bends sharp enough to be banked, for example freeway on/off ramps and junctions, etc). The sound is a grind-esque 'wub-wub-wub-wub'.

My mechanic put a stethoscope on and sure enough, bad bearings just as I had thought. I haven't fixed them yet as they want $250 each. I'll probably end up doing them myself, if I can rent a press for the bearings.

Hope this helps.

Kmizzal00TL

Thanks for the input guys!

When I first heard the noise I replaced the drivers side front wheel bearing and hub. The buzzing/whining/humming noise is still there, it's not like a cyclical wub-wub-wub noise. I've had the axle/boots/joints, passenger side wheel bearing, the dust plate and even the half shaft bearing on the drive shaft checked. All are good. No tranny leaks either. That mechanics stethoscope seems promising though. I'm pretty sure my mechanic doesn't have one, but maybe my tranny guy does I'll post an update.

01tl4tl

do you have a Harbor Freight Tools in your town? go there and buy 2 mechanics stethoscopes, under $5 each
Keep one and gift the other to you mechanic

or go to any local parts store and buy 1 for under 10 dollars
Looks like a Doctors stethoscope on top half, and the end is a pointed rod that looks like a meat thermometer tip. Place the tip on areas you want to listen to, practice on alt, and ac belt tensioner to know various bearing sounds.
That tensioner likes to wear out-
Listen for smooth vs gravel sounds to know bad bearings