I'm sure this has been covered 100 times, but the threads I've found don't have satisfying answers. What are your thoughts on an AWD to FWD conversion for a failing or leaking PTU? I simply don't have $1,500 to drop on a repair to literally have it happen again, which we all know is the case. Physically, this is my idea. Starting at the back, you could remove both axle shafts, the rear diff, the driveshaft and stop there. The problem with that method is eventually when all the fluid leaks out, the friction will cause the gears to fracture within the PTU, and honestly it's a crap shoot if it breaks the transaxle-side gear or one of the others. Potentially it could resolve itself (once it breaks, if the transaxle side continues to spin in the case, you've won the lotto, you're free!) but more realistically it could lock up and keep the transmission from spinning, and toast the transaxle.
Alternatively, if you were to remove all of the above components, and in addition the PTU as well... then pull one or all of the gears out of it and then reinstall it... you would just have the transaxle shaft spinning alone inside the PTU case. Mechanically this is sound, no danger to other components. Remember that the whole AWD system spins idling at all times until the rear dif solenoid engages it and puts an actual load on it. But, this is where the problems come in though... the ECU will likely notice the lack of input from the AWD system. How? I'm not sure. Maybe the Rear diff solenoid would have to remain hooked up to some extent, just so the ECU is happy it can ground the circuit properly at will? How would the ECU know we've disconnected the system? The tires should all spin at the same rate for a given speed, so RPM signal would likely not be valuable feedback for if AWD is active or not.
I appologize for the rant, but I'm interested in salvaging the remainder of these wonder vehicles, despite the ONE glaring flaw of the PTU. So I guess one bit of homework is how does the Edge even differentiate the torque front to rear? If the AWD system right up until the rear diff solenoid is always active (spinning), and it's mechanically, permanently geared, to the transaxle, how does the car "split" torque? Some cars that have a center diff can split torque 20/80, 60/40, etc I don't see that happening here because there's no center diff. So would this even affect the driveability of the vehicle, and will this set check engine lights? (and how?). Thanks in advance, let the conversation begin!