Pretty general question. It gets COLD where i live. Soooo I say check your antifreeze and other fluids. Check your battery connections. Put your top back on. Make sure you have gloves and jackets in your jeep. Check that your roll bar mouted Keg holder is tight, Oh and check your supercharger belt and toss on your boggers for all your snow wheeling runs im sure you'll do!
I throw a blanket in the cab, one for me and one for the kids. Not sure if it is folklore or science but I also put some cardboard in front of the radiator-Mythbusters is doing an episode on that one right now. MN winters hit below zero so we have to take it seriously.
Don't think that TJs are invincible in snow. They spin like a top if you go faster than you should on slick roads. I know first hand. Deep snow like 12"+, you'll be alone out there with the National Guard hummers, but that 1/4" stuff can make you over confident and do a 720 on the interstate going 70mph.
Install seat heaters $70 covers both front seats. Winter hit us today, high of mid 60s but driving at night when it was 60 going 65mph with the top down felt so good with the heaters on!
Thought you were going to say I put sun block in the Jeep...
ASSUMING you have REAL winter ie -20*... I change to 5w-30, switch to winter wiper fluid, check anti-freeze. Winter box goes in Jeep, gloves, hand warmers, Coffee can/ candle, Food that doesn't freeze, essentially things I would NEED to get me through an over night storm I may get caught in. etc. approx 200# of sand bags go in back. Chains etc.
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