I have a 2015 EX-L 3.5. Between 40-45 mph the car vibrates just cruising. Looking for causes.

 

These are kind of hard to figure out on the internet....please don't take that the wrong way.

The list is long. It could be an issue with the tires, an engine/trans mount, something in the drive line (cv shaft), ect.

Should still be under warranty (?), you could take the service manager from the dealer for a "ride along" and let them feel what you are feeling and see what they say from there.

 

i've been to the dealership. They claim they didn't experience the issue during test drive. Vibrated on the way home. My next thought is to rotate tires front to back. Know someone is wrong.

 

Rotate and balance the tires is something that should be done every now and then so doing it to try to narrow down the issue isn't a "wasted" expense....so to say.

If you know the right conditions to make it happen. Go to the dealer and YOU drive while the tech/service manager rides in the pass seat. I've done this before when I was having an issue with one of mine.

Wish we had better answers for you on this.....someone else might chime in with more suggestions.

 

My 2014 EX V-6 also has a vibration but it's related to RPM. At between 1500 and 1800 I get a slight but noticeable vibration, regardless of speed. I've become used to it but sometimes it bugs me.

 

Check the outer edges of your tires, see if they are cupping or scalloping, ie. sections raised or lowered. This causes vibration and not only on turns.