With the HIGH rate of transaxle failures of the earlier MDX's with the VTM-4 F/awd system how could even the MDX with the SH-AWD system have made it into the top 10...?
Almost all of these newer F/awd systems, SH-AWD system included, pre-emptive rear drive engagement systems, are experiencing high failure rates of the over-stressed drive line components as a result of "locking" the center "diff'l" even on the most tractive of road surfaces. And "locking" the center "diff'l" in turns, while turning, accelerating turns...
SHEER IDIOCY.
Driveline windup and/or tire scrubbing will be at its WORSE measure in tight accelerating turns, thoroughly over-stressing, HEATING, various driveline components. MDX transaxles' lockup clutch and Ford Escape and Mariner PTO's currently top the failure list.
But if you start out with a SOLID drive coupling to the front wheels then compromises in the name of safety MUST be made. Locking the center "diff'l" while turning in order to reduce the drive torque to the front wheels thereby allocating more front tire traction for lateral forces is then a MUST.
Or like an actual FWD you could make TC EXTREMELY quick and agressive, ALWAYS. Which it is anyway if wheelspin/slip develops even with the rear drive engaged.
This same post, with slight variations, appears on many discussion sites and under a variety of makes. No evidence supporting the statements has ever been provided for any of the makes.
Yes. I agree. I currently own a 745i, it's been 10 years. The driving is very additive and I really enjoy this car. However, it has issues and it's not cheap to keep up with it. I never had big problem with it but all the small little problems could unfortunately cost a lot more than a Toyota. I recently test drive a Acura RL (2010) and was actually very impressed by it. I had an Acura Legend, had it for 13 years and really loved the car. I thought Acura has the closest to BMW driving feel. I am seriously thinking about trading mine to the RL. My wife is looking for a SUV (used or new) and she is trying to choose between the MDX and Cayenna. I know they are very different but since i had never own a porche before, not sure if Porche makes good Suv and how expansive is it to keep up with the service and repairs ??? Any thoughts on this will help. Also, i am in L.A. and do porche dealers here sell it below MSRP?? thx
The older MDX' that used the VTM-4 F/awd system has had, is having serious driveline failure problems. Those seemed to be solved with the switch to the new SH-AWD system but now as of 2010+ transaxle failures seem to be rising again, recent "reflash" TSB even.
Comments
Almost all of these newer F/awd systems, SH-AWD system included, pre-emptive rear drive engagement systems, are experiencing high failure rates of the over-stressed drive line components as a result of "locking" the center "diff'l" even on the most tractive of road surfaces. And "locking" the center "diff'l" in turns, while turning, accelerating turns...
SHEER IDIOCY.
Driveline windup and/or tire scrubbing will be at its WORSE measure in tight accelerating turns, thoroughly over-stressing, HEATING, various driveline components. MDX transaxles' lockup clutch and Ford Escape and Mariner PTO's currently top the failure list.
But if you start out with a SOLID drive coupling to the front wheels then compromises in the name of safety MUST be made. Locking the center "diff'l" while turning in order to reduce the drive torque to the front wheels thereby allocating more front tire traction for lateral forces is then a MUST.
Or like an actual FWD you could make TC EXTREMELY quick and agressive, ALWAYS. Which it is anyway if wheelspin/slip develops even with the rear drive engaged.
But also no evidence against my position, just statements like that above.
But logic is on my side, clearly.
I currently own a 745i, it's been 10 years. The driving is very additive and I really enjoy this car. However, it has issues and it's not cheap to keep up with it. I never had big problem with it but all the small little problems could unfortunately cost a lot more than a Toyota.
I recently test drive a Acura RL (2010) and was actually very impressed by it. I had an Acura Legend, had it for 13 years and really loved the car. I thought Acura has the closest to BMW driving feel. I am seriously thinking about trading mine to the RL.
My wife is looking for a SUV (used or new) and she is trying to choose between the MDX and Cayenna. I know they are very different but since i had never own a porche before, not sure if Porche makes good Suv and how expansive is it to keep up with the service and repairs ??? Any thoughts on this will help. Also, i am in L.A. and do porche dealers here sell it below MSRP??
thx