The front driveshaft spline issue is at the TC so when it happens the front drive shaft doesn't spin.

The symptom describe a loose CV axle or perhaps a blown CV joint (depends where the turning stops).

If the front drive shaft (propeller) is turning it means the TC is working and also means that power is being applied to the diff. the front side is bolted unlike the back side which is just spline poked into the TC.

Replaced doesn't mean fixed. If the CV axles are locked in, the symptoms described a defective dif.

Odds are far better a CV axle is not fully installed or the splines in/out of the dif are worn .

Put the car in N and allow all motion to stop before P. The grinding is the parking prawl. But you should not need to use the engine power to resolve.

If one of the CV not engaged, you'll likely be able to turn that wheel by hand. When you try to power from the engine side if either side slips neither side moves. It should be a little easier to turn the side that's not engaged as well as the pop from the spline slip should be much easier to feel on the CV axle that's slipping.

About once a year these symptoms come up on xoutpost. It has almost always come out to be spline engagement out of front dif. One time was a blown dif.

Worth car in park attempt to turn one of the floating front wheels.

When working properly the other wheel will turn the opposite way. The front drive shaft from TC shouldn't turn.

Pre 04 the TC doesn't disengage the front axle but I can't remember if it's locked with the parking prawl but I do know that anytime I've turned a front wheel by hand the opposite wheel turns the opposite way so that's the test to perform.

If you don't get that result the problem is at the dif.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)