Hi. I have a 1991 Dodge Ram W-250 diesel 4x4 that's Red. I am wondering about putting an AC unit in it. It has factory AC but it doesn't blow very well. I don't see a lot of options for this truck specifically, but Vintage Air looks like it might fit. The truck is all original (mostly anyway) I am not an expert but everyone I have shown it to thinks its original. It has power side mirrors and cruise control which I was surprised to see. It's been sitting in my garage for 3 years and I either need to get it drivable or sell it, I guess. The AC is really the only thing I need to drive it. Well, that and put in the new seat belts that I found out I didn't really need to get. LOL.

 

Does it not move much air, or does it just not get real cold? Is it still R-12? Or has it been converted to R-134?

 

Factory A/C is usually the best. Does yours need a recharge? I'd convert it to R-134. Personally, I just recharge the older systems but I still have a case and a half of R-12.

 

It doesn't move much air, the air is cold just not a lot of it. I should have been more clear about that point. I don't know if it's been converted or not. Is there an easy way to tell?

 

See if there are adapters on the pressure ports, and maybe for the switches.

Does the heater blow good? If not, may just be debris that accumulates in there, clogging things up. So far as I know, ALL the air goes thru the evaporator core regardless of what setting the temp is at.

 

That is a good point and I need to check the heater core. I wish I had more time to work on that truck.

 

The air on my '96 only blew out the floor vents. The blend door had a broken. Rather than pull the dash to replace everything, I drilled a hole and ran a wire to the inner door. At full blast, the pressure holds it in place. From what I remember on my '84, there may be vacuum hoses that actuate the mechanism.

The original A/C system on your truck is R-12. The connector ports are the same size. If your truck has been converted, there will be adapters put onto the ports.These will ONLY fit particular connections on the gauge sets. The low pressure adapter is smaller than the high side. Either way, the R-134 is larger than the little R-12. If it's been changed, you can use the charging kits sold at the parts store. They will ONLY fit the low side.