I'm pretty much baffled at this point. I'm still getting the sloshing/water running noise near the firewall at startup and sometimes when I accelerate. I've had a pressure test done, nothing out of the ordinary. Bought a new radiator cap, didn't do anything. I burped the system and it's still doing it and it is still using coolant. In 2 days the overflow will be empty from when I filled it up. There is no coolant in the oil so I can eliminate a head gasket problem I'm assuming and the water pump was replaced last year in April. The floor board on the passenger side isn't wet either and I don't get a coolant smell when the heat is on. Does anyone have any suggestions on this. I still say I have a leak somewhere because of it using the coolant and the idiots that did the test lied to me...or didn't do it at all. Also my rear main seal is starting to leak and so is the seal on the back of the transmission. Does anyone know what the official name for the seal on the back of the transmission is? It connects to a circular like part which is in turn connected to the driveshaft.

 

Output shaft seal.
If it is still sloshing then burp it again. Check all of your freeze plugs for coolant, especially the one hiding behind the motor mount on the driver side. If they aren't clean and dry then clean them off and see if they get coolant on them within a couple days.
My heater core had a bunch of pinholes in it and was leaking for quite a while before it finally started to fog the windows, the floor was dry too, it was leaking into the evaporator case (hvac case maybe, can't remember the name for sure).

The rear main is an easy enough job. You won't have hardly any oil dripping on you if you drain it out and wait about a day before pulling the oil pan. Make sure you get anaerobic sealant for the rear main bearing cap, it's loctite 518 (summitracing is the only place I've seen it) or permatex anaerobic sealant (at advance).

 

It must be my heater core then. My window's fog up if I don't have the ac on. Thanks sheriff.

 

Yep. I had the same problem with pinholes in the heater core.

 

I've heard mixed reviews on how hard it is to replace this. Some say you have to remove the dash. Others say you can remove the screws and move the dash just enough to get the core in and out. What do yall say? Also, would this solve my problem of the truck using coolant? I just looked at the freeze plugs and they are all dry.

 

It is easier if you remove the steering column and dash, but it can be done without removing them.
Yes that is where your coolant is going.
Do the windows fog up immediately if you kick on the defrost on heat?

 

Yep. If it's raining and I have just the air blowing the windows fog up completely. Have to have A/C going or the defrost on cold when it's raining.

 

Then your heater core is definitely shot.
I bet it smells like a wet basement when you kick on the heat too.

 

It doesn't though, thats the weird part. But I'm tired of putting coolant in the radiator every 3 days so I think I'm gonna have to try and tackle this one. I hope my dash doesn't crack any more than it is.

 

When I did mine I just snapped off all the pieces and threw a molded plastic cover on it (take that dorito dash!).