I just wanted to know if anyone knew what causes my truck to produce which almost smells like roofing tar once and a while. The thing is i had the smell also come from old 05/4.7 and my one of my fathers vehicles which is an jeep liberty gets the same dam smell at first it was in summer and i was ok someone is retaring a roof but next time it happend was in the dead of -40 weather and on 3 different vehicles all dodge brand also. One of my fathers friend said it could be the transmission vac line ? this one stumps me!?!?

 

Msybe sticking brakes or oil-/trans fluid dripping on exhaust.

 

If you're smelling it in multiple vehicles... it's your breath.

 

 

Haha but being serious iv had it happen on both my rams only cruising at slower speeds say 50km hr and my father gets the same thing going up hills .hes friend mech said its the trans vac lines he had them fixed but still gets the same thing what ever it is it come threw the heat vents?