2007 Toyota RAV4.
So the car (suv) has around 180,000 miles on it. It’s my moms and has been a good car so far. Not too long ago it started making a noise. She (my mother) took it to several shops and best anyone could come up with was a “transmission” issue, without any fix. I’ve noticed when driving it that the noise only happens when the car shifts down, like you’re going up a hill and it shifts down. It makes a rumbling noise kind of like when you sit your cell phone on vib and it goes off on a table. It doesn’t seem like it hurts the cars performance any just a bad noise. Any help would be great.
Note the RPMs when it downshifts. Then rev the engine to that RPM in neutral or park and see if you get the same sound.
Have you checked the level/color of the transmission fluid?
Here’s what to look for when checking the color.
http://myautomatictransmission.com/transmission-fluid-color.htm
Tester
The drive train of a Rav4 is complicated because it is 4WD. Transmission, transfer case, 2 differentials, and lots of CV joints. Have the fluids the transmission, transfer case, and differentials ever been changed? If no, at 180K miles you might have some bearings starting to go bad, hence the noise and vibration.
A bad CV joint is also possible. You can inspect the CV boots and if any are torn and show leaking that CV is then suspect.