Flowmaster 17428 American Thunder Cat-back Exhaust System

Ok so here is the deal, after months of reviewing similar products I chose this one for its price and the reviews, this fit my 2002 gmc sierra with an extended cab and a standard bed and a 5.3 vortec engine, I love the look of the dual exhaust and it sounds good, nice low rumble and peak noise at 1700 rpms so its quite at highway speeds, the only reason I gave this 4 out of 5 instead of 5 is because when I put this on I didnt have a way to remove some of the old bolts to bolt it together ended up costing another 100$ to have a shop remove the bolts and finish the job, if you habe a torch or a way to remove the original pressed in bolts this is perfect, overall a great exhaust

I will confirm the installation woes that others indicated. I had to weld the exhaust to keep it on the truck. The hangers that come with the exhaust are not very well designed. I decided to weld washers on the end so that the system would not vibrate off the hanger. If you don't weld, I would suggest you plan to have a muffler shop do the installation. Now the good part, it sounds great on my 5.3L HO. Low rumble at idle, low and mellow on acceleration, and an aggressive rumble when you downshift.

I used the fitment tool to purchase this product and I have a 2007 Chevy Silverado New body style 5.3L. The fitment tool does state that this product fits my truck but it does not. the first pipe that connects from the flange you bolt on to the muffler is bent too much making it impossibe to fit it to my muffler. The rest of the system fits perfectly using all of the pieces and pipe hangers. I paid 558.00 bucks for a bolt on system that wont bolt on! I had to use the existing stock pipe first and put on a 12" extention piece to fit to the muffler. The issue is the 1st instructions say CUT OFF YOUR EXISTING PIPE BEHIND MUFFLER AND REMOVE. BY THE TIME i FIGURED OUT IT WOULDN'T FIT I HAD NO MUFFLER AND PIPES I JUST CUT OFF MY TRUCK. I think the fitment tool should be updated. Sense part of the system fits I should have to pay part of the price!!! This way a huge inconvienience I love the sound and performance just wish it would of fit without mods.

Completely woke up a sleeping beast. Sounds like a Chevy V8 should now.

We ordered the incorrect unit number. It is very difficult to choose the correct system using most WEB pages. We reviewed several other competitive sites to obtain the correct system number for a Chevy Silverado Step Side, Standard Cab and Short Bed model. Amazon exchanged the unit for the correct unit as researched. We also found that you have to dig deep into Flowmaster WEB page to confirm a correct fit description. We would advise future purchasers to Go To an automotive parts store if any doubt about compatibility exists.

I purchased this cat back vehicle specific system believing it would be an easy install. Only it wasn't for my vehicle. I've got a regular cab long bed they sent a extra cab short bed system. Before I removed the old I matched up the pipes and found the pipe after the cat was a foot too long and the hanger bracket a foot too far off. The rest looked ok so I decided to have to cut 12 inches off the pipe and relocate the hanger before the muffler. Other than this order mishap It seems fine.

This exhaust bolted up easily on 2001 GMC Sierra. Everything fit perfectly with no modifications. Only took us about 1 hour to remove old system and get the new system installed. Has a nice deep tone now.

I’ve bought Flowmaster my whole life. Their quality is going down hill fast. Their tailpipes rust within 2-3 years. This kit will be the last one I ever buy. None of the hangers were welded in the right places. The pipes were bent in the wrong places. I had to cut and modify it. I’ll never buy this brand ever again.

Fit and finish was great, didnt take long to install. Was missing a piece but seller made it right. One complaint is I wish they sent better clamps, but they work

Wow what a nice kit thanks I would buy this again