[km0hr1337]

Alright, so I've had this car for just over a year. I bought it as my first car and it had 96,575 miles on it. It is a 1-owner vehicle and the previous owner took good care of it. Since purchasing, I've taken care of it. I've taken the car to get its oil changed twice since I bought it, and recently, I got my car's automatic transmission fluid topped off. Now, I'm still in high school (I have four months left...yay), and other than knowing how to change lightbulbs and add windshield washer fluid, I do not know anything about cars. My car has been making this low-pitched humming sound when I accelerate, and quite frankly, it's been bothering me recently. The car used to make a rattling sound at low RPM and speed. I had a front bar mounted to the front bumper (I originally wanted to put some auxiliary lights in but I never got around to it). After taking it off, the sound got quieter, and stopped rattling often (it only does it from time to time again and honestly it's hard to say when because it does it at irregular intervals). I did some research and have come to the idea that it may be my exhaust heat shield being loose. What's worse, and what's really been bothering me, is the likelihood that I have a bad torque convertor. Now, mind you, the car shifts alright. It drives decent so I don't think it has to do with my torque convertor much less it being a transmission issue, but like I said, I do not know much about cars. I just want to understand what could be wrong with my car. I plan to take it into a mechanic soon to have them check it out, but I'm hoping this won't cost a fortune to fix.

I've linked a video below to what my car currently sounds like. It now has around 107k miles on the odometer. If anyone has an idea of what's wrong I'd love to know. Thanks for reading! (P.S. Sorry for putting this in the wrong forum section if I did, I am new to this forum site.)

 

[Flat6er]

1) please, don't say that because previous owner followed factory maintenance schedule - that's why you say that car has been taken care of?
it is called - abused car(that's probably another topic in future ))
but let's not focus on money hungry corporations, individuals and their actions.

2) the sound part is hard to identify, but first thing to check would be - is it RPM-specific or is it speed specific? it sounds to me like lower rpm sound... might be auxiliary belt or some tensioners. you might test it by removing said belt and try it out (just do it in safe conditions)!

3) about transmission - I would suggest get yourself FSM ( USDM Tribeca 2008 FSM ) and read FSM\Transmission Section\Automatic Transmission 5AT\ files - 4 Road test, 5 Stall test, 6 Time lag test and 7 line pressure test.
that might help you to understand what is your situation there.

also - if you would like to do stuff yourself (especially diagnostics) - get yourself cable/adapter and software to read error codes, live parameters etc etc (probably, again, another topic)

p.s. congratulations on car