The answer "buy a new truck" implies that such an action is easily accomplished and completely ignorant that one's personal financial situation is not the same as another's financial situation. Be polite and assume that the truck the person just purchased is likely the truck the person can afford and work within the confines of that situation.
On a similar note, the death of a forum for being useful can happen when those who have been around the longest post terse, answers based off of their tribal knowledge and experiences. Instead of just jumping to the least imaginative answer we should strive to make ourselves useful by taking the problem for what it is and doing our best to solve it based off of the variables provided. Only after we have exhausted all options and suggestions with no answer should we offer the suggestion that the vehicle in question may not be suitable for what he desires to do. The answer wasn't the problem, it is how it was said that was...
This isn't a hit against anyone in particular. Most everyone here seems to be pretty good about offering opinions that are both helpful and polite and these people keep this forum interesting and worth coming back to.