I have 4 torque wrenches, 1/4" and 1/2" Snap-on digital, a 3/8" Snap-on Digital Tech Angle and an inch pound dial type Snap-on with follow up needle (for Pinion Bearing pre-loads). I highly recommend the Snap-on digital torque wrenches, but they don't come cheap at all. I use them all frequently, (except the one for differentials). BMW does use a good amount of torque-to-yield bolts, (where the torque spec is a certain amount plus certain degrees of rotation.) But I think a 3/8" digital Torque Angle wrench will cover almost all of those. I also have an adapter dial for measuring precise torque angle that can be used for the 1/2" wrench, but so far I've made do with my 3/8" Tech Angle. FYI, CDI makes many torque wrenches for Snap-on, so that may be a less expensive route to get a really good torque wrench.

FYI; having a good torque wrench is NOT the only issue. You must rotate them smoothly and not too quickly when approaching the proper torque, (waiting for the beep or click); or you could overshoot as much as 20%. Some things really can not tolerate that much extra torque. I just recently had a tire shop change the tires on my wife's 325xi, and insisted on the tire jockey using a torque wrench. He did comply, but gave each bolt an extra push after his torque wrench clicked, (what an idiot!) So I had to teach him how to use a torque wrench. The first few he put on, I retorqed at home and found them over 160Nm; spec is 120Nm. Even after I showed him, the rest were off by 10-15% in varying directions. (Just a crappy wrench I guess). With the digital wrenches, you can easily measure breakaway torque as well. Thankfully BMW lug bolts are very strong; 20% overtorque will easily snap a stud on most Japanese cars.

If you do get a digital torque wrench, unless you use it constantly, leave the batteries out. You do not want a battery leakage in a $600 torque wrench. It's interesting that the Snap-on digital wrenches remember your last setting indefinitely even with no batteries.

And if you decide to buy a used one, unless you really know it was never dropped, have it recalibrated. If you do critical stuff like engine building or differentials, have it calibrated regularly.

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2014 BMW 328i Xdrive
2011 BMW 335i M-Sport
2008 BMW X5 4.8i Sport
2000 BMW 528i 5sp