98 Ram QuadCab. All air goes to defrost. Gets plenty hot but cannot get to dash vents or floor vents. Any ideas??

 

You have a vacuum leak. Do a search on this forum for vacuum leak. Lots of people have posted this problem and also posted were they found the vacuum leak to fix it. That will give you a good place to start because finding the leak can be a son-of-a------.

 

i have seen this problem before. it is the a/c switch. i had to replace mine. the top ****, the one which selects whether floor, vent, or both, ect. Mine would still turn but it blows out the defrost vents no matter where it is. I replaced the switch and it fixed it.

 

Ya actually, that sounds more like your problem then what I first stated, or you could have lost all vacuum. If it is only a vacuum leak like I first stated, it will switch to defrost only under load (like when going up a hill), but the rest of the time you are not on the throttle, it will blow out of the correct vent. So if you can never get it to blow out of the correct vent, then it could be your switch or you have no vacuum at all.

 

thers a fella on ebay sellin one right now for cheep to... search under dodge ram switch and youll get alot of search options to look for..