One day i get in my truck lunchtime only to smell an acrid smell...smelled like differential oil with posi fluid to me. Really strong. Go through whole truck, check tranny,differential...u name it. No leaks anywhere. Finally bring to toyota.they say...it smells like cat piss. Interesting i say....dont have a cat,never did,never had one in the truck. Oh...they say. We can try an a/c refresher kit..killsmold etc. In system. Ok,...now the car smelled like cheap bathroom spray...for days. Finally wearing off. The smell is coming back. The heat and a/c seem to work fine. Toyota says its an organic smell and the next step is pull the dash for 1000 bucks.i dont think so! My 200k mile 4runner runs great....but that smell, i dont think i can tolerate long term. Anyone have a clue what to do?