Yes - LLC with several members is generally considered as partnership.
A partnership is the relationship existing between two or more persons who join to carry on a trade or business.
Each person contributes money, property, labor or skill, and expects to share in the profits and losses of the business.
A partnership must file an annual information return to report the income, deductions, gains, losses, etc., from its operations, but it does not pay income tax. Instead, it "passes through" any profits or losses to its partners. Each partner includes his or her share of the partnership's income or loss on his or her tax return.
Some additional information about partnerships may be found in IRS Publication 541 - http://www.irs.gov/publications/p541/index.html
The LLC may choose to be treated as S-corporation. You may read more about different business structures here - http://www.irs.gov/businesses/small/article/0,,id=200274,00.html
Members should not "sell" trucks to the LLC. If trucks are used for business - they are depreciated. If trucks are used partially for business and partially for personal purposes - the basis for depreciation should be prorated.
You may find more details in IRS Publication 946, How To Depreciate Property - http://www.irs.gov/pub/irs-pdf/p946.pdf
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