My 2000 TL started vibrating while going 50-60 m.p.h. under mild acceleration like when going up a small incline on the highway. It goes away by simply letting off the gas pedal but annoying when trying to pass a truck or something on the highway. There's no Check Engine Light happening. I have replaced the following with no luck:

Engine mounts (front & pass. side)
Spark plugs
Front Axles (both)
Wheel bearings (all four)
Tires balanced

The brake pads and rotors are new and the engine operates fine otherwise so I'm stumped. Anyone have more ideas?

 

I had the same problem, but mines was @ 40MPH. It was the innerjoints on the axle drive. It only vibrated while acceleration. Check your axles, if thats the problem then your going to have to replace both left and right axle drive shafts, so they can wear evenly.

 

There's another thread going on about this. I checked the wheels and changed motor mounts...bearings and axles are next.

 

The car has about 180k miles so I already replaced both front axles and all the popular things that cause this.

 

if i'm not mistaken, its the transmission. my car did the same thing at 20-40 mph, and after the transmission replaced, everything works fine now. well mine was still 78k, and was under the 100k warranty on transmission. so you might have to spend a few grands to fix that if u're willing to. in your case, it might be the 5th gear.

 

This sounds to me like the classic symptom of the lockup torque converter. If it is indeed the torque converter, then it is basically trying to lock-in/lock-out the overdrive gear. It tends to toggle back and forth around the 50MPH range, I bet if you downshift teh vibration will go away.

 

On some Acuras its because of the ball joints wearing out.

 

Gear has no effect. It's only under acceleration...meaning it will go away during automatic gear shifts, if I let off the gas, or if I shift to neutral.

 

yeah, my car does the samething it shakes when i hit 50-60mph.. then when i hit 70 and up it stops.. so i also wats wrong wit the car.. i guess it could be the wheel bearings..

 

is it just doing this when the car is cold?
mine does that only when i drive and the car is not fully warmed up.....

 

Mine is more pronounced when it's warm and has been driven a few miles.

 

mine does it cold and warm. I've thought about the coil packs possibly going or a clogged fuel filter.

 

mine does it when its cold and warm

 

If it only does it during a certain range, like lets say 20-30, or 40-50, and never happens when u go higher than that, i'd say it's ur transmission. that's when they shift the gear, and u feel the vibration. if it continues after that range, then that's a different story, might be what other people suggested. but like i mentioned before, definitely get ur car checked out if it's still under the transmission recall warranty (7 years/100k miles). My dealdership charges $125 for labor if no problem is found. but they found the problem after a few test drives n fixed it for free.