Please Help...chatter while shifting

[1QuikV6]

I have a knowledgable mechanic that says my drivetrain noise is coming from the crank. What I want to hear is that it is tranny related. When shifting gears, there is a clatter that sounds like lifters knocking, I doesn't happen all the time, only when hot chicks are in a car next to me (it seems). aka Intermittant. We recently replaced all the rod and main bearings hoping that would quite the knocking sounds eminating from the motor. No help

The motor has 87k miles on it and it's mods are in my sig. I'm just hoping the noise COULD be coming from the tranny and not the bottom end. Wishful thinking?

I'm turning to you guys because I'm hoping someone else here has had a similar situation.
My tranny is flaring and starts bucking when I mash on the gas. Having trouble going into passing gear and raising hell doing it? I'm using a Jay Carter street chip. ATV is NOT at factory settings because the darn thing is stretched too baddly. I've adjusted it till I have firm shifts.

Thanks in advance gents.

 

[1QuikV6]

Nobody has any insight?

 

[turbosam6]

Sure sounds like tranny to me. I would think the crank making noise wouldn't be dependent on shifts, it would most likely do it all the time. Hows the oil psi on the motor? Is this at WOT only? On my car if I don't secure the cooler lines just right they rub and usually around the shift they will vibrate and make a buzzing sound. If this is at WOT only, could it be valve float, i.e., original springs are weak? I had a knocking noise that would come and go on my car, but it turned out to be an exhaust leak. Drove me nuts, it was so intermittent.