I have a 2002 dodge ram 1500 4x4 with the 4.7L v8 with 246,000 miles. The knock/ tick started about a week ago and is loud when warm; it is still there a little when cold, but it sounds intermittent, but when warm, it increases with engine speed. I also know that the back bottom bolt in the exhaust manifold is broken and the gasket is broken. A little more info the noise is very quiet or nonexistent when looking under the hood; it is the loudest standing beside the front door on the passenger side. The belt tensioner is a little loose and was making a ticking noise, and the belt has started squealing recently, but I don't think it is the noise because you can't hear the noise while looking under the hood, but could it be? I did the screwdriver sound trick with the oil pan, and you can listen to some sort of knock/ tick. I also did an oil change recently I put 6 quarts of 5w 30, and the dipstick says well; if there are any questions, please ask and please contribute any information you may have. I will add a video audio clip for it and a few images tomorrow.

 

A knock/tick sound can be caused by a broken exhaust bolt.
You should also address your belt tensioner. The tensioner has a scribe mark and two limit marks ("I" and "II"). Check that the scribe mark is in between the I and II. If scribe mark is all the way to one side then either your tensioner has a weak spring, or, your belt is stretched.

 

is there a way I can test that the exhaust manifold is making the noise like sticking a pry bar on it and prying it away from the engine carefully and do you know of any ways to solve the problem if it is the manifold? also, I will replace the belt tensioner and maybe the belt I just haven't had a day that I am free and it is not freezing outside.

 

You will need to replace the broken manifold studs and the exhaust gasket. Can you tell whether the stud or bolt is broken? Is there any stud sticking up that you can grab with vise grips?
What would you be checking by prying the exhaust manifold away from the head? I don't think there is anything to learn from that and may make the problem worse.

 

when I get home I will take a picture of the broken stud from what I remember it is flush with the manifold so I will have to remove the manifold grab it with vise grips or weld a nut to it to remove it. furthermore, my idea with the pry bar is to pry it away from the engine so it if making the noise will stop contacting the head and stop making the noise. that is at least my idea and frankly, I think it is maybe stupid enough to work but I don't think it will work and may make the problem worse.

 

You aren't going to flex a cast iron manifold. Unless of course, it just breaks...... Also, if you were able to pry the manifold away, it would get worse, not better...... you would be opening up the exhaust leak.

 

I will not do that now thanks for the input and telling me how bad of an idea it is. do you have any ideas for testing if the manifold Is the cause of the noise? quick side notes why would it be very quiet or not there when cold but loud when hot? please tell me any ideas thanks for your help

 

Grab yourself a 3 or 4 foot section of garden hose. Let the engine idle, and when it starts making its noise, stick one end of the hose to your ear, and use the other end to 'sniff' around trying to localize the noise. If it's loudest right near the manifold by the broken studs, that is highly likely to be an exhaust leak.

 

Thank you and I will do that thanks for letting me know.

 

I tried the hose trick I couldn't hear anything around the exhaust manifold but the bottom end is very noisy. I am going to attempt to put new bearings in it I will update at some point. thanks for all your help and a couple of tricks!