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Old 11-21-2012, 07:38 PM
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lbjgh lbjgh is offline
Officially Welcomed to the 'Fest
Location: North of Toronto
 
Join Date: Dec 2011
Posts: 712
Mein Auto: 2013 X3 M-Sport
The following response was from a former member on the other forum.

I trust his response.

Quote:
The "nominal" value is 89 lb./ft, but any value within the range of 85 to 101 is acceptable. As I recall, those values came from a translation/conversion from the German Owner's Manual. Any value you set with a torque wrench will likely have an error associated with it. The best "analog" torque wrenches (bending beam) are accurate to about +/- 5% and the very best ($200 and up) digital wrenches (Gearwrench or Snap On) are accurate to about +/- 3% or so when recently calibrated.

That "nominal" torque reading is for clean, dry, but NOT greased or oiled lug bolts only.

Also, because of the bolt thread pitch as compared to the E83, (M14X1.25 compared to M14X1.5) the actual bolt tension (and the force holding the wheels to the hubs is 20% higher on the F25 chassis. A F25 bolt at 89 lb./ft. is actually putting more holding pressure on the wheel than a E83 bolt at 101 lb./ft.

As always, it's best to approach the final lug bolt torque reading in a couple of stages. IE: First torque all bolts to 10 or 20 lb./ft, then all to 50 lb./ft. and finally all to 89 lb./ft. in a standard "star" pattern.

Of course, with alloy wheels, some settling-in due to "cold flow" always occurs. Most wheel manufacturers recommend re-torquing the bolts after 500 miles, but hardly anyone but serious racers ever do it.
Quote:
Originally Posted by gfeiner View Post
Not 90 for the F25. Torque is higher for the M14 bolts used by F25.
Its 140Nm which is approx 103lbFt
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