yeah,bigg boss is right,at first i tried with sketchup too but everything was really boxy and it was just horrible,i suggest you 3ds max because with some tutorials i found (also posted in 3ds tutotials section) i can actually model on my own (not really good but waaaay better than sketchup)
Added 4 hours 7 minutes later:
Here's a compare sketchup VS 3ds max,both modeled by me 😃
Sketchup:

3Ds:

Note: 3Ds exhaust looks solid filled but it isn't,unlike the sketchup one