Been awhile since I have posted... I am usually offering stupid advice, not asking for it.
The culprit is my 2005 PT with a 5-speed.
Background - this is most likely the most abused PT on the highway, as I am in semi-tractor driveaway services and tow this car behind tractors to delivery - hop in the PT and go to the next job.
After logging over two million miles in these things, I have been up against most issues more than once and do the lion's share of my own repairs and overhaul.
As such, this PT has logged 450,000 rolling miles and 210,000 under power. This is PT #5 for me.
BUT, this one has a pretty wild shimmy that exhibits itself ONLY on harder acceleration and around 45 through 60. Brake rotors are new and fine - no hot spots. Recently replaced both front axle bearings - all seems well and torqued properly. Front to back tire change? I discounted tires as these were rotated and balanced about 2 thousand miles ago. Seems to have been gradually occurring, so...
I changed out the CV axles last year but I am tending to blame the axles again or bearings in the trans. I have another trans in my shop. The weight of the car with me, the equipment and a tank of gas is right at 5 thousand pounds.
the steel I built and carry... and a typical hookup to tow the PT...