Thank you guys for running a great forum, you've helped me with a lot of my projects, but I wasn't able to find anything on my particular question.

I'm replacing the exhaust on my '93 S10 Blazer from the cat back and all the tubing from AutoZone fits neatly together, but the exhaust guide on their website said I need some sort of grease or joint compound around the ends of the tubes before I slide them together. The guy at the store had no idea what I was talking about, so I'm asking the real experts.

Do I need a joint grease or is just clamping the pipes enough?

 

I finally found what you were referring to on their website. It's 'GM Sealing Compound No. 1051249 or equivalent'. I only clamped exhaust pipe one time, and learned better. I've always had them welded since then, but I've never known anybody to use any compound, grease, etc when clamping exhaust pipe.

 

The coumpund actually works pretty good. It is a paste that you put on the pipes before sliding them together, then you clamp them. When the putty dries, it forms an airtight seal, sealing any small leaks from the clamping.

 

I owrked in a service center for a couple of years, we never used any compounds on the exhaust work, clamps work well and have for decades. What ever you use on the exhuast will burn off over time. They do make a compound to seal against leaks and it may help when assembling the pipes, but its not really needed unless your pipes aren't round or tight. I like to use some sort of spray lubricant when slideing pipes together, generally they are a bear without some sort of lubrication, again it will burn off so don't be alramed by the smoke or funny smell, unless it doesn't go away.

Happy clamping.