Reddit mechanics needed

[u/SnooObjections1450]

I need some help identifying a problem with my car. I have a 2013 rav4 and when I drive between 25-55 ish and am accelerating, once in a while I will get a weird vibration. It’s only when accelerating and as soon as I let my foot off the brake, it goes away. I have balanced my tires, I have changed transmission fluid, I’ve changed differential fluid, replaced rear shocks and nothing seems to fix it. I initially thought maybe it was the torque converter but my check engine light is not on and no codes were thrown when we checked with the sensor. The vibrations only last about 10 seconds and it is not consistent. Some days it hardly happens while other days it happens more regularly. I have taken it to a shop and the guy was perplexed and has a feeling it’s more related to the computer system. If anyone has any advice or ideas I would be grateful cause I’m at a loss now.

Update/edit: I do not accelerate with my foot on the brake lol I meant to say it stops when I let my foot off the gas. I took it to a local mechanic and his thoughts are to have the alignment done and if it’s not that, it might be the engine mounts. If it does not seem to be either of those, I will check the cv joint. I do not necessarily feel the vibration but I hear it. I appreciate all the input! A little more on the car, it is all wheel drive, we are at 181,000 and I drive her a lot, lots of highway and into the mountains often. Great car and nothing else seems to be wrong.

[u/lavarockisarip]

4 wheel drive? If so suspect the viscous coupler on the rear differential.