Hello all. A few questions about a quick fix i have read about. I have the 1800 rpm howl in my '99. It only happens when the truck is warmed up. I have read that an easy fix is to remove the rubber restrictor washer from the fitting that connects the block to the heater hose. Apparently the washer sets up a cavitation at certain rpms that creates the noise - makes sense if you've heard it.

My questions are have any TDR members done this? Did it work? Why is the restrictor there in the first place? Is there any risk to removing it? Thanks everyone, JB.

 

Well, I couldn't wait any longer and just went ahead and did it. Good news! That aweful sound I've been living with till now has gone away. What a difference! I have ordered a new fitting that is supposed to cure the problem according to the TSB on it, but unless someone can tell me why I should not have removed the restrictor, I think I will cancel it. Anybody?

 

Mine has no restrictor, did not know that one belongs there. What does it do?

 

I don't know what it does, other than make a racket. When my brother drove in my truck for the 1st time he noticed the noise right away, thought it might be the tranny whining (it is louder on the passenger side). Inside the brass fitting on the cylinder head that connects the heater hose to the fire-wall is a little tapered rubber washer, kind of looks like a little garden hose washer. It is there to serve as a restrictor of some kind, as its bore is smaller than that of the fitting. I had to pry it out with a screwdriver. On Fritz's Dodge site, they list the TSB about the noise and the p/n to fix it, but others have written in and said they just removed the restrictor and the noise went away.

http://dodgeram.org/tech/dsl/trouble.../isb_noise.htm

That's what I did, and it worked, but I am wondering why the restrictor was there in the 1st place.