5.9L Freeze Plug Problem leaking coolant

[HansonM]

I am continually having a problem with the rear freeze plug blowing out on my 04' Dodge. It only has about 56K miles on it, but the rear freeze plug has blown completely out twice within 2 months. Someone said that there was a TSB out on this, but I am not sure. Does anyone possibly know what is causing this or if there is in fact a TSB issued on this problem? I have to drop the transmission to get to this thing which is a pain.

 

[R_Painter]

I have heard that the repair can be done with trans in place. The reason it is blowing is a lot of pressure on the coolant system with the thermostat closed. If you pull the trans I put a couple of big washers in the recess of the freeze plug and put asteel plate over it. There is two bolt holes back there that helps alot. Inbetween the washers and the plate I put a sealer to seal everything up.

 

[jwilliams3]

Is your truck modified at all? If so list the mods.

 

[Shadrach]

Check out this in the 12v forum https://www.turbodieselregister.com/forums/showthread.php?t=154204

Shadrach

 

[CTD 600]

There was a TSB on this back in 2004

 

[rbattelle]

Here's a long discussion about it...



Link



Ryan

 

[HansonM]

Yes my truck has Dr. Performance Injectors, Module, Super 62 Turbo, and the module stacked with a PPE. It is putting down 564 at the rear wheels so i would assume that is part of the problem because of the pressure.

 

[jwilliams3]

Here is some info you might appreciate:



Dont get on the truck until the engine has cycled the thermostat. This will prevent pressure build which can cause a plug to leave the engine block.



Check for a blown headgasket. This could be a helper in pressurizing the coolant system and cause a blown plug.



Another thing:

Since you have had your plug replaced it makes me wonder if they did the install correctly.

If you dont have the right tools for the job you can easily damage a new plug or install it canted or incorrectly. Not something I would let any joe schmoe do to my truck.

 

[HansonM]

I have head studs in and there does not seem to be any blown head gasket or any other gaskets... I do remeber that I romped on it pretty hard and had it running about 124mph when the thing blew out... It was also about 10-20 minutes after I started the truck and got on the highway, and it was about 27 degrees outside so mabye the thermostat had not cycled yet. . I am thinking of trying that plate issue fix I see other members doing on my year model.