BMW 3 series Owner's Manual page 278

Do not tow the vehicle with just the rear axle
raised as this may cause the steering to turn.
With a tow truck: vehicle with xDrive
Do not tow a BMW with xDrive with just
the front or rear axle raised; otherwise, the
wheels could lock up and the transfer case
could be damaged.<
Have the BMW transported on a flatbed surface
only.
Tow-starting
Avoid tow-starting the vehicle whenever possi-
ble; instead, jump-start the engine, refer to
page 274. Vehicles with a catalytic converter
should only be tow-started when the engine is
cold, vehicles with an automatic transmission or
Sport automatic transmission with double
clutch cannot be tow-started at all.
1. Switch on hazard warning flashers, comply
with local regulations.
2. Switch on the ignition, refer to page 60.
3. Shift into 3rd gear.
4. Have the vehicle tow-started with the clutch
depressed and slowly release the clutch.
After the engine starts, immediately
depress the clutch completely again.
5. Stop at a suitable location, remove the tow
bar or rope and switch off the hazard warn-
ing flashers.
6. Have the vehicle checked.
With xDrive: do not activate Hill Descent
Control HDC when the vehicle is being
tow-started, page 97.<
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