Black cars are a bitch to photograph in bright sun. That said- the first one is underexposed- the 2nd is better.
BMW pics look fine exposure wise though- some of them could use a little fill-light slider though.
believe it or not most of these were taken with the 70-200, so yeah i did zoom in, i guess not enough..
What was your aperture?
as for the background suggestion, since both of these cars are from the same era i didn't feel that the industrial setting was wrong for them, i went to these places because i like them, i like the way the sunlight hits the different spots at different times of the day.
The BMW is often looked at as a yuppie vehicle. A city scene or modern, glass & steel, office complex would've been a better location. The truck worked better where you were.
the last two pix of the bmw are odd to me. the car's fine, but the background seems so indecisive. like you'd have wanted to flash the car just to underexpose the background out more. it's a weird sort of limbo.
did you have a choice about when you shot these? looks like midday-ish, when light is harshest. good kill getting ANYTHING out of that truck. needs more flash to bring it out
it was a little later than mid-day, probably 2-3pm.. the last 2 bmw shots are actually underneath the over hang in the shade, i was trying to get the bmw to "stick out" vs the darker background.
That's most of your problem. Still too early in the day. Also, the BMW is white- it's going to naturally stick out from the background.