Awful Noise

Hello All!

I just purchased a 2001 Jeep Cherokee with a 4.0 and an auto transmission. It apparently just needed an oil pump, which I replaced, but when I took it for a test drive I found another issue.

The engine starts and revs fine in neutral and park, no issues in drive either, but when I rev it in reverse it makes this awful sound. See the video below.

I have been told it could be a cracked / loose flexplate but I wanted to get your opinions. The flexplate doesn't appear to be cracked but I've only examined 1/3 of it.



https://www.youtube.com/watch?v=R4TiMw1K6ew

Thanks!

The flex plate does not know if it is in Drive or Reverse. My guess would be a broken motor mount and the sound would be the fan hitting the radiator.

Motor mounts appear fine, no damage to the fan or radiator.

Tom is right, the flexplate spins the same direction for forward and reverse (neutral and park too). It could be the reverse drum inside the trans, noise is very loud like its right there with you

If it isn't the motor mounts, I would tend to say it is the tranny. I say pull the tranny. If the flex plate is shot, stop at that point and replace it. Otherwise, start looking for a replacement tranny.

I'd pop the hood and put it in reverse and have someone stand on the brakes and give it a bit of gas to see if you can hear where the noise is coming from. it sounds too loud to be inside the trans.