[brian37]

Hello,

I have a 1991 Astro, the AWD version. I'm trying to replace the muffler & exhaust pipes, and I'm confused about the necessary parts.

So I found this: Muffler Exhaust Pipe System Fits GMC 1985-1991 Astro Van 4.3L Rear Wheel Drive | eBay

And it seems very specific that it is for the RWD version. However when I search for the individual parts for my VIN# on Advance Auto Parts, the same extension pipe, muffler, and tail pipe part numbers come up, and the other part numbers listed I can't seem to find.

Just to confuse me even more, the only video guide I could find for the job was this:

- but it's on a 94 model, so I'm not sure if the clamp sizes he mentions (two 3inch and one 2.5inch) are correct for mine.

And finally, the pipe off my catalytic converter definitely doesn't look like the one in the video guide (please see mine in the picture below) - is it supposed to look this way on a 91?

Thank you in advance to anyone who can help,
Brian

 

[markmitch]

Certain years of the first gen vans had what was known as an HO exhaust system, which was only a bigger tail pipe, but the rest was pretty much the same. If you order the parts and some don't fit, you can buy adapters to make it fit.