Yes i think a strenth ten troll plus can lift a sedan minimum the front half of it.
The ballance and such are just my flavor text as thier is no stated improvment in the stat block.
Your being limited on how seating can be arranged in a vertical manner.
A strength 10 troll has a base lift and carry of 100 kg. He can roll (str+body) and use additional hits at 10 per kg more lift and carry. So on an average day a body 8 str 10 troll is going to lift and carry 160 kg. That same troll can lift (deadlift, basically) 240 kg.
A vehicle's mechanical arms have a (base) strength equal to the body of the vehicle (AR 102). The maximum augmentation is +5 STR.
Your vehicle with augmented arms would have 19 str, 14 body. That's 190 lift and carry base, and 33 dice means an average expectation of another 110 for 300 kg. If you can turn it to a straight lift that goes to 450 kg. Your vehicle weighs between 1000 and 1500 kg - simplify it to 1200 kg.
With load balancing and locking the arms so they're basically crutches instead of limbs you could do this. I'd require a maneuver test, it'd be slow anyway, but it's within the realms of possibility.
Using the arms as crutches doesn't let you go down building hallways. It lets you pass under lower bridges.
The base lift and carry limits are 15kg per strength lift from ground, 10 kg lift and carry, 5 kg lift overhead, with hits from STR+Body adding additional increments. (SR4A 139) I would rule supporting the body for crawling equivalent to lift and carry.
At 19 (14 body +5 augmentation) STR that's 190 base kg. 19 dice is nominally 60 more kg, making your vehicle capable of supporting ~250 kg for crawling. At a typical weight of 1000 to 1500 kg for a sedan, you're not using your mechanical arms for crawling. Even allowing for mechanical load distribution (three limbs down at all times) you're still going to be short.