I have a 2002 Nissan Maxima 3.5L V6 SE with 61k miles on it. I had the car for about 14 months with zero issue but randomly it started making a rhythmic thumping noise from directly under the driver side footwell only in SELECT conditions, this started at about 59k miles.

These conditions are:

• Heavy acceleration from stop like 3-4k RPM from idle will make a continuous rhythmic thumping consistent with RPM until let off the throttle.
  
• Heavy acceleration while at highway speed (60+ MPH), same thing.
  
• Going over sharp bumps like pot holes, speed bumps, deep grooves in pavement, will make a noise from the same location.
  

I have had almost the entire suspension gone through by 3 shops and they can't find anything wrong.

Here is the list of things I have been told are good and I have inspected myself as well to find no issue.

• CV Axles have been inspected, boots are fine, no play in the axles, no clicking noise when doing circles.
  
• Sway bar links and bushings have been replaced at 60k miles on both driver and passenger front side.
  
• Wheel bearing / hub replaced on passenger side at 60k miles, no issue on driver side.
  
• Sub-frame bushings are intact with no sign of failure/degradation on both front and rear part of front sub-frame.
  
• Struts and shocks were inspected and are intact with no leakage, no excess movement when car is moved at a stop, rebounds just like it should.
  
• Brake pads and brake rotors were replaced at 50k miles.
  
• Front and rear engine mounts were replaced at 52k miles.
  
• Driver side control arm / bushing & housing replaced at 52k miles. No issue with passenger side control arm / bushing.
  
• Transmission fluid / filter changed at 60k miles, shop reported no metal on filter or in pan. Car shifts beautifully smooth.
  
• Tires changed when purchased at 50k miles. Rotated every 5k miles since, (55k miles and 60k miles)
  
• Oil & Filter changed when purchased at 50k miles, changed every 3k miles since, no metal in pan or on filter.
  

The only thing that even looks remotely wrong is there is a tiny bit of play on the flex pipe exhaust hangar. It is close to the sub-frame but I can't push it remotely close enough to hit it, so I don't think it is that. It resonator also sits close to a stabilizer bracket, but again, there is no play at all with the resonator.

The only thing I can realistically think of is something internal is beginning to age on the driver side CV axle or the driver side sub-frame bushing is worse than meets the eye.

I appreciate the help since I am a graduate student strapped for cash and have always loved 5th Gen Maxima's so I really want to make this work, but can't spend a fortune having the whole front end gone through.

 

Welcome to the forums!

I'd say attach a GoPro or other camera on the underside of the car and go for a ride. Hopefully that will help in pinpointing the source of the noise.

 

when you changed the front and rear lower engine mounts did you replace the 2 upper mounts? as well as the bushings on the beam that the mounts attach to? even though the car has low miles rubber is no match for time..

when changing engine mounts it's best to do the whole set at once. the upper mounts on these cars aren't designed as solid as the lowers.

is your car automatic or a manual?

 

I vote for exhaust. Engine mounts are flexing on acceleration causing exhaust to contact.

 

I feel your pain - had this with my 1st car (not a maxima). You say heavy acceleration but that is not 3-4k, its 5-6k. are you certain about that RPM? I also second the idea of a gopro but I would put it inside the engine bay with a light but be sure to make sure it is held tightly and there is plenty of light. The things that come to my mind is the belt tensioners, tires for many reasons, Sorry if I am steering you wrong.

 

I think you hit the nail on the head. The trans-mount and passenger engine mount (side engine mounts) are probably just as shot as the front and rear engine mounts were when I had them replaced.

Also probably the reason, none of the shops saw them is that the side ones are buried under a ton of **** with covering discs on them. Hell the trans-mount is UNDER the air intake for crying out loud.

It just makes the most sense, also I noticed that the car bucks a bit when you are at highway speed and give it a little gas (aka shifting from 4 -> 3) as well as going from D -> R.

 

If it vibrates, sounds like CV to me