Hemi MDS Ticking,…. Lifters or Exhaust Leak? You might get LUCKY!


If you are a Hemi vehicle owner who has a ticking engine, you are for sure not alone. There is the normal “Hemi tick” that just means you have a Hemi (that may do it forever with no real change) and then there are the more serious variety of noises that tell you “something isn’t right”.

The second type means you should probably be worried. If something is truly not right now, then it means things might REALLY go awry soon. If that something is a lifter ticking then you may be close to a serious failure that might take out the engine completely and you’ll be up for a replacement engine or a full rebuild of yours. In this case it really is best to diagnose the issue and possibly discontinue operation to prevent major problems.

But what if you have serious noise and the problem isn’t so dire? Many Hemi owners have discovered that a bad tick has turned out to be an exhaust leak caused by broken exhaust bolts on the heads. This is most common on the very rear most exhaust manifold bolts closest to the firewall.

This turns out to be much less troublesome than an internal problem such as lifter failure and cam lobe issues. On the above picture, (which is showing the rear-most exhaust port on a passenger side Hemi cylinder head) you can see the broken exhaust bolt and the black area on the head where the exhaust gasses are bypassing the exhaust manifold gasket.

The exhaust gasses getting by the gasket in this case will cause a sharp tick that mimics a lifter or cam problem. In a lot of these scenarios the tick is worst at start up and will slowly fade as the engine warms up and everything swells up with heat, causing the exhaust leak to eventually stop. I once owned a 2010 Challenger with the MDS 5.7 Hemi that exhibited this exact symptom.

I was very glad to find the right rear exhaust manifold broken (exactly as shown here).

My advice if you suspect this might be your Hemi issue? Grab a stiff piece of hose around the size of your finger, around 4-5 feet long. With the vehicle cold, have a friend start the engine. Being VERY CAREFUL, stand back a bit and hold one end of the hose up to your ear. Fish the other end all around the rear of each exhaust manifold, starting on the passenger side. If you have a decent exhaust leak and you hold the hose end right over it while the other end is in your ear, you will be able to distinguish it pretty clearly. MAKE CERTAIN YOU DO NOT MOVE THE HOSE END NEAR ANY MOVING PARTS SUCH AS THE BELT ETC. You’re going to be focusing on the rear of the engine so you should be fine.

If you suspect an exhaust leak, remove the exhaust manifold on that side to see if that is the case. Sometimes the bolts will just be loose or the gasket will be blown. Of course if you are able to see that any of the bolts are missing / broken off, and or the hose test comes up positive, you are probably on the right track and you probably got lucky and will not be requiring internal engine work.

A broken exhaust bolt in the head can be a pain but it’s much better than needing to go into the engine for lifters, camshaft, etc.

Knowing it’s an exhaust leak before you take it to your mechanic is helpful. Believe me, people have paid for a full job of lifters, camshaft, gaskets etc etc, when all they really needed was a stud extraction and new exhaust gasket.

Hopefully this post will help someone who thinks they have more wrong than they really do. It is not a good feeling to know your vehicle needs repairs, but it may not be as bad as you think!

If you do need lifters, we can help you there just click on “shop lifters” above.

Until next time! Have a good one!