I have a first generation QX50, and since those forums are dead and this car shares basically everything with a G37, I figured I'd ask you all a couple of things:

• I know the 3.7 isn't a particularly smooth engine, but mine is a little bit boomy at idle. I doesn't vibrate an excessive amount; it's more of a low-frequency 'boom' at the 600-650 rpm idle, and is reminiscent of some 4-cylinders. I used to have a V36 G35 (yeah, much different engine), and that did not do this. Is this normal operation for the 3.7?
• When accelerating from a stop in first gear, the transmission has a slight high-pitched whine. Not always, but most of the time. I have not checked the ATF... because I can't. It seems to go away by 10-15 mph. Is this normal?

The car in question is a RWD 2016 w/32k miles. I'd assume plugs are fine, and air filters are new. I cleaned the TBs (they were surprisingly dirty, but does that even do anything in a VVEL engine?), cleaned the MAFs, ran a bottle of BG-44k through it, there are no codes etc.

Thanks.

 

SO in other words a QX50/EX37. Depending on the condition of the filters and how dirty you saw the the TBs I would suggest plugs.
You should still be under warranty so why not take her in?

 

Correct - a first generation QX50. Yes, the car is CPO and has plenty of warranty left, but before going to the dealer and saying something like "my idle feels kinda-sorta less smooth than I think it should" and likely getting a "no fault found" or whatever, I was curious if this is something that is characteristic of the 3.7. With regards to the whine, that seems easy enough for somebody with the same transmission to answer.

I thought about plugs, and I suppose I'll pull one out to check. Seems odd that 105k plugs would be worn enough to cause anything out of the ordinary at only 32k, but who knows how the original owner treated this thing.

Thanks

 

the RPM thing is normal. Not sure about the whine, never had it. Change transmission fluid.

 

My G kinda whines at idle and in 1st gear but from 2-7 it’s silent. Idk what it is Many people say they got it too.