I'm late (again), to my ears it's like it's had a blanket pulled over it. Great suggestions from everyone who got to the party early. 

It just occurred to me: you might look into phase problems, too.

Really good tune.
 
I agree there's something funky w/ the low end (maybe low-mids).  Have you tried looking at it w/ a spectrum analyzer?  There's a good, free one here: http://www.voxengo.com/group/free-vst-plugins/ (span and span anspec).  You have a lot of vibrato on your voice (sounds great, but it's a reality).  If I were mixing this, I'd try trimming the low end of your vocal and seeing if that helps.
 
Peace,
 
Ian
 

There's a wide upper mid that almost  hurts.  Sweep with your eq and find what jumps out and reduce.  Kick need more volume and punch .  Vocals are a bit washed into the mix.   Sounds like phase/flange which makes it a little weird on the ears.    Some mentioned phase.. could be

I always had a problem going from studio to truck till I got a sub in the studio. In the mean time A/B your mix with a commercial track that you want a comparable sound and see if you can make up the difference in the mix.
 

Ok, spent sometime this week...wondering if I am really hearing it anymore, I have heard this about a million times.  Hopefully this version is better....
 
http://soundcloud.com/bla.mire/iou-mix-16-03302014

This sounds pretty good.  Traditionally, the vocals would be a little louder and the watery guitar turned down a hair (they are both in the same vague range but guitars and vocals always fight).  Sometimes I'll use the channel tool to place things out of the center and more confined in the center.
 
But it sounds pretty good to my ears otherwise.
 
@

if you had more of a bigger chorus in the track it would bring more of an emotion in your voice! just my 2 cents! good song.

To my ears, this mix sounds balanced and natural coming through my Rokit 8's.  I don't drive a truck, but I think it would sound good in my 2000 Honda Accord.  Sometimes you just have to take a break from listening to a song over and over so as not to skew your perspective.  Move on to something else, and then come back to this at a later time, and I think you'll be surprised at how good this sounds.

thanks all! I think this version is much better than the first. I made changes based on all of the comments. I will give it a few days and listen and see what I think.