The problem with independents is that sometimes they are not up to
date with the factory recommendations, and they work on older cars.
Most BMWs built before 1990 probably had such low specs (heck I think
for the 2002ti, it was only 60 lb-ft).
The factory recommendation for the E46 is 120 Nm +/- 10 Nm (88 lb-ft
+/- 7 lb-ft).
Torqueing itself won't warp rotors, but the expansion from heat buildup
will, and to what I have read and heard the torque spec is devised to allow
expected expansion without warping. I know on certain cars with certain
composite rotors, the WJ grand Cherokee for example, torque levels at the
lugs is a huge issue with keeping rotors true. So I don't think bfd's
concern is unfounded, I just don't think it is well premised if the
specified, or close to specified, torque input is used.
Sure it does. Had no problem with my 328 when it was new. After the dealer
took the wheels off during service, the steering wheel would jerk to one side
as I applied the brakes when coming to a traffic light. Went back and told
them to torque the wheels properly - no more problem. (Could have done it
myself, but I was pissed) Turns out the dealer couldn't properly balance the
tires either. I decided to end our relationship.
You risk warping the rotors mostly when you have uneven torquing. I
don't think 10 ft/lbs one way or another will make any difference. You
toirque wrench is not likely to be that accurate anyway... Repeatable,
yes, but absolute accurate, no.
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