My question involves employment and labor law for the state of: Indiana

My employer pays me 17.00/hour
I have a take-home company vehicle and a credit card only for fuel

I am required, every day, to travel from my home, to my office, to retrieve equipment. I then drive 1 hour to a job site to work an 8 hour day. At the end of the day, I'm required to travel 1 hour, straight to the office to drop off time-sensitive samples and the equipment I picked up at the beginning of the day. I then travel 2 miles to my house and park my company vehicle for the night.

My employer pays me for 40 hours of work on a paycheck with taxes taken out and benefits deducted ect...

I get a separate check for $175.00 with no taxes withheld, this check is called "travel compensation"

I believe my employer should be paying me for 48 hours of work each week totaling $935. ((40 hours x 17.00) + (10 hours x 25.5))

Instead I get $855.00 (40 hours x 17.00 = $680) + ($175 travel money)

I feel like I'm being shorted, I'm also concerned about the $175 of untaxed income I'm receiving each week.

Is my employer breaking the law? I know this would be different if I was traveling straight from home to the job site each day, but I'm not, I'm going to the office first. I feel like the clock should start when I get to the office and begin loading equipment and it should end at the office when I unload the equipment.