Permanent fix, Drill a small hole(1\8") in the thermostat. You will never have this issue again! The hole will allow the air to escape. You may also consider putting 180* stat in it to run cooler. Down side you will probably notice a slight bit less heat in the winter.

 

Drilling the hole in the stat makes it easier to get air out of most of the system, the problem lies with the heater core. It is slightly higher than the engine (inlet/outlet) and will trap air in there that is almost impossible to get out with normal burping methods. Really not sure how dodge though that was a 'good idea'.......

 

I drilled a hole in the stat when I replaced it a year ago. And this is the only vehicle I've had that the temp fluctuates so much. It will go up to 210 then back to 190 all day depending on what I'm doing. When I hook a really heavy trailer to it. It tends to creep up and not want to come back down. Especially when I'm backing it into my driveway. Low rpm trying to move it around is worse then anything. I've tried my hill outback to burp the system and it still seems to be about the same

 

What mix do you have in there? How old is the radiator? How old is the coolant itself?

 

I would have to wonder if your heater core isn't starting to plug up. My truck fluctuates a little bit but only during the first few minutes of driving. I've hauled about 5,000 lbs over 225 miles and never saw it get anywhere close to 210. It won't hur it to run close to 210. Your heads are probably already cracked anyways. You could put a 180 degree t-stat in it. I have one in my Dakota and the heat blows plenty warm. It just takes a little longer to get there.

 

Are you cranking your heat when burping it???

 

The heads definitely aren't cracked. I had compresson and leak down test dome before I bought the truck. I think it's just air in the system cause I can hear it gurgling\ waterfall in the heatercore. I just can't get it out no matter what. I've tried everything I know. The head gasket is fine. It doesn't bubble with the cap off. Plenum good. Dam things has a air locked bubble that don't want to come out. With a 180 stat won't the computer stay in open loop? Being a 94 idk . I'm not sure if the computer has to see 195 for it to close the warmup loop. Any ideas on that one?

 

Should go in to closed loop at around 108 degrees. The older trucks don't whine about 'engine too cold too long' either. Supposedly.

Disconnect the heater hoses, on the passenger side, right where the hose splits. (about the middle of the valve cover.) Disconnect drivers side hose from the steel tube into the water pump. (have something ready to plug that hole, as coolant will spill out of it.)

Raise both hoses above the level of the inlet/outlet for the heater core. Add fluid to the driver side hose, till it starts coming out the passenger side hose. Clamp off both hoses to retain as much fluid as possible, and reconnect them. Should take care of the air bubble.

Another option is to install a 'flush T' into the outlet side of the heater core. (drivers side hose) Start the engine, crack open the T, and it should purge all the air fairly quickly. Then, just top off the system, and you should be all set.

Will that change your truck running hotter under load? Probably not.

 

Okay I just got done putting a 180 stat in cause I haul a trailer alot with the truck. I took the camper for a ride for about a half hour I went down the mountain and back up and the temp maxed out about 195 with the 180 stat. I was trying to was put alot of strain on the truck. So I'll keep the 180 in but. I think it's just masking the real problem for now. But if u say the older trucks don't worry to much about running cooler. Then I'll be content. The heat is decent so I guess it's a temporary fix to a impossible perminent problem. I've been reading 100 topics about 180 stats and I think it will be alright. I have a empty cat so it won't clogg that up. I think obd2 trucks have more issues then obd 1 trucks do with it.

 

OBDI is a lot less picky.

How old is your radiator?

I have an old tractor..... yes, it's water cooled, that if the temp was above about 75 degrees, it would only run for about 45 minutes before it tripped the overheat shutdown circuit breaker. (at 220 degrees....) The radiator developed a leak, so, I took it in, and had it re-cored. Now, even when it is 90+ degrees outside, the temp never goes above 180.... (which, coincidentally, is the thermostat temp)