I have a 96 SE 5spd with 96,xxx miles. A couple of days ago, I started hearing a humming noise coming from the engine/transmission. It starts to get real noticeable around 70MPH. It sounds like a bearing gone bad and its dependent on vehicle speed not RPM. When I'm cruising and hold in the clutch to let the RPMs drop, the sound stays the same. About 4 months ago I rotated the tires, changed both axles, and replaced pads and rotors all around, and I've driven a couple thousand miles since, so those things are ruled out. Is is common for a 4th gen manual tranny to go bad under 100k miles? The car is all stock and rarely gets beaten on. I dont even like downshifting to slow the car down.

 

Almost sound like a wheel bearing man. Raise the car up and check for any play in the hubs.

 

Probably diff bearings, one of the more common problems in Maximas. Incorrectly set up pre-load from the factory, from what I understand.

 

I was thinking that too, but at low speeds, say I'm in second gear, I'll hear like the gears almost meshing. Funny thing is all the gears go in no problem, and it never pops out of gear either. I've been in school since the noise started, but I have work tomorrow, so I'll definitely put the car on the lift and double check everything.
I can accept if I need to get a new tranny, just dont want it to happen right now while I'm going to school.

 

Whats the worst that can happen if this is the case, i.e. would the tranny sieze? And how long would it take to happen?

 

Sounded like mine. Alot of clatter in neutral and while driving. Eventually, 1st and 2nd went out. Rebuilt it, no problems. I just have the whine from the wheel bearing

 

I just hope I have the option to rebuild it before I get stuck somewhere. BTW, lifted my car today and everything in the front end is nice and tight. It was really hard to tell if the tranny was making noise though, cause of all the other noises I gotta fix first.

 

Did you check that the axles were tight? (push up/down on the axles where they enter the transmission...there should VERY little movement, <1mm) Are you leaking transmission fluid at the axle seals?

If the noise is speed dependent and the above two things check out fine...you have one or more defective wheel bearings.

Edit: Also, did you change the MTL when you did the axles and what did you use?

 

I'm gonna say wheel hub assembly as well. that happened on my old eclipse. I used the slide hammer to get it off and it came off in 2 pieces and the bearings were crushed.

 

from what you describe this sounds like a wheel bearing, not transmission related.

 

OP, do you notice these sounds when you turn? Do they get louder or almost shake your car?

 

had a problem like this, replace the bearing

 

check the axels to, possibly the brakes too

 

Just an update

It was the wheel bearing. Thanks for all your replies. It was mostly the driver side one, left some brown spots here and there due to heat. I replaced both though, including the seals. I would say it took a good 2.5 to 3 hours to do at the shop I work in using a lift and air tools. I had to use a bearing tool though because we don't have a press.

Just outta curiosity, I checked All Data and the labor time is listed at 5.1 hours. One of the perks of my job is using the lift/equipment at no charge

Old Bearings:


One of the new bearings packed: