[Bob with the 66]

Trying to figure out what the ticking noise could be. It started a couple months ago.

Can only hear it when the engine is driving under load, at idle no noise. In park no noise.

Seems like it could be coming from the passenger side of the engine. I tried running premium gas, no help.

Tick gets quicker as the truck get faster, I laid under the truck while running in park and do not hear any exhaust leaks.

Wouldn't a lifter tick all the time?
Engine runs and idles great, has always been a gas hog.

What could it be, all input welcome, Bob

[Chief of the 60's]

You are in a rusty area. Rusty areas are known for exhaust manifolds and/or exhaust manifold gaskets. It is common on Ford, Chevy, Dodge, Toyota, etc. in rusty areas.

[Bob with the 66]

Originally Posted by Chief of the 60's

You are in a rusty area. Rusty areas are known for exhaust manifolds and/or exhaust manifold gaskets. It is common on Ford, Chevy, Dodge, Toyota, etc. in rusty areas.

Chief,

I hope your right, I'm hoping external and not internal fix. The trucks exhaust is probably the rustiest part, it does sit outside all year on the drive way.

[Chief of the 60's]

Originally Posted by Bob with the 66

Chief,

I hope your right, I'm hoping external and not internal fix. The trucks exhaust is probably the rustiest part, it does sit outside all year on the drive way.

LOL! You may regret it being that too. If you are going to tackle it yourself, the best way I found to do it is to knock the heads off the bolts, pry the manifold off and remove the rusted bolt like a stud. You will have a nightmare on your hands if you try to remove the bolt as a whole and it breaks off in the head.

[77 Canamman]

This is a common problem with every single manufacturer's trucks from that period. Bad quality manifold bolts and salt spray do not mix..

[Chief of the 60's]

Originally Posted by 77 Canamman

This is a common problem with every single manufacturer's trucks from that period. Bad quality manifold bolts and salt spray do not mix..

GM and Toyota manifolds are also known to crack. I think Ford too but can't remember.

[ponchjoe]

If not manifolds I’d check the cat conv to make sure it hasn’t broken loose and started rattling.

[Bob with the 66]

Well I'm happy that it could be just a gasket and not a lifter. I do not know if this is something I want to tackle without a lift and a welder in case I break a bolt.

Now that I know where to look, tonight I'll get a better picture on how rusty the manifold and bolts are and determine my next step.

Thank you to everyone that has given guidance, the Pontiac community is full of great people.
Bob

From U Tube, it looks like heat from a torch is also required.

[Bob with the 66]

So I finely had a chance to slide under my truck and look for an exhaust leak. First thing I notice is a wet spot on the frame, attention has quickly changed to what's leaking.

I have a brake line leak above the gas somewhere, so the exhaust leak is now on hold.

Needs brakes, I can live with an exhaust leak for another week or two.

Bob

[steve v]

Rusty brake lines are pretty common on these trucks. My '04 2500HD had a line go right next to the fuel tank a few years back, rusted thru. Looking at the rest of the lines going to the abs unit under the drivers floor area was an awakening also....everyone of those lines look like they're ready to go next. Was a little surprised they rusted this bad seeing as we live in NC with very minimal exposure to winter weather/salt brine on the roads here.

I bought a complete pre-bent steel brake line kit from GM that had every line in it for right about $100. Seems like they were a plastic coated steel line so hopefully they'll last a little longer. I was able to replace the line in between the tank & frame w/o removing the tank. Good luck with your repair!

[marxjunk]

Originally Posted by ponchjoe

If not manifolds I’d check the cat conv to make sure it hasn’t broken loose and started rattling.

this is exactly what mine did, and no one could diagnose it..pulled the converter loose for something else and it had broken apart and was ticking inside the case...

[77 Canamman]

Originally Posted by steve v

Rusty brake lines are pretty common on these trucks. My '04 2500HD had a line go right next to the fuel tank a few years back, rusted thru. Looking at the rest of the lines going to the abs unit under the drivers floor area was an awakening also....everyone of those lines look like they're ready to go next. Was a little surprised they rusted this bad seeing as we live in NC with very minimal exposure to winter weather/salt brine on the roads here.

I bought a complete pre-bent steel brake line kit from GM that had every line in it for right about $100. Seems like they were a plastic coated steel line so hopefully they'll last a little longer. I was able to replace the line in between the tank & frame w/o removing the tank. Good luck with your repair!

Stainless steel and vinyl coated prebent kits are readily available. I've done so many of these I can do them in my sleep. Fortunately, the 2007-up trucks all have the vinyl coated lines.

[Chief of the 60's]

Originally Posted by 77 Canamman

Stainless steel and vinyl coated prebent kits are readily available. I've done so many of these I can do them in my sleep. Fortunately, the 2007-up trucks all have the vinyl coated lines.

They rot too. GM needs to recall that junk. But then, it took them awhile to recall cars that were killing people, brake lines are not important.

[Simple Man]

Is there a way to dump maybe some ATF in the throttle body? All the smoke 'should' pinpoint a leaky exhaust.

[Chief of the 60's]

Originally Posted by Simple Man

Is there a way to dump maybe some ATF in the throttle body? All the smoke 'should' pinpoint a leaky exhaust.

That would probably cause more harm than good on a computerized, fuel injected vehicle.

[Bob with the 66]

Update, my truck was leaking at two exhaust ports on the passenger side. Repair went well, I heated the head with a torch around the bolts and took all out without breaking any!!!

Manifold was warped, new Dorman manifold, ran a tap to clean the threads, a little copper ultra on a new gasket and new bolts.

I also had to replace the down tube, as it fell apart when I removed it from the manifold.

To all, Thank you for the help, your input helped me greatly!
Bob

[Chief of the 60's]

Good deal! I figured that was the problem.