On my 2018 diesel there's a 2wd, 4wd (hi/lo) and auto. From what i've read the auto uses clutch packs in the transfer case to engage the front axle when it slips. But since there's a 4wd option does that mean it has both clutch packs AND a full lock for the front axle?

 

Nah. Your transfer case just has a large chain in it. No clutch packs. Your axles, usually rear axle, will have a positraction to lock up the wheels. You might have to use an oil additive, if you use a non-GM fluid for the axles however. Your TC uses an electral motor to switch from high to lo range.

 

visit GMC.com.when- to- use-four-wheel-drive
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