not really or doesn't effect, you just needs to make sure that how is the car and its running condition. my both car has 4.6L V8 no problem till now. one has 128k miles and one has 54k miles.
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My friend, listen one thing, I had own many bmw, landrover, mercy benz, ford, and lexus.
BMW is expensive to fix. it is not good car for young driver. in this range you can look ford i have 97 T-bird 4.6L with 124000 miles and no problem till now, my friend has same car he has 279000 miles and...
if the car is in excellent or better condition DOn't drive go to the dealer.......... most of the time its trans problem......if it has high mileage. sale as is.