Often with a big purchase like a car/truck a husband likes to know the specifics so he can make sure of the value and what can go wrong with said vehicle. That's something my husband would be concerned with especially wanting to make sure it's safe for me to drive. If used my husband prefers to have a mechanic he knows and trusts look it over to make sure it's ok.
I have a feeling it's more than that though and am not sure my statement will help much with the overall Thing that keeps bothering you.