For those wanting a good sound without the full cat back system, installed flowmaster 40series, single out and was surprised how well it sounded on H3 3.7L. Left on resonator for now (afraid of cabin drone if remove)but may take off once the muffler breaks in. Will try to post sound later.

 

I have that setup on my H2 & am very pleased with the sound!

 

have a flow master on my 3 and the resonators removed... sounds mean when i get on it and quiet when im just driving normal... little bit of a dron but when i get on it its meannnn.....

good choice on the flow master..

 

954 can you post a video or audio clip of how your truck sounds? Ive been wanting to do a new exhaust for a while, just been waiting to hear the right sound!

 

Yeah, from what I've heard on youtube and a few in person, you can't go wrong with the sound of the 40 series on the I5 motors.

 

What muffler part number did you go with? I've been wanting to go with the series 40 but didn't have access to my rig to figure out if it was 2.5" or 3" inlet and whether it was offset or not. What did you go with?

 

tagged.............

 

There's quite a few vids on YouTube for the Flowmasters on th I5 or Alpha.
Here's some of them:

I-5
Hummer h3 with Flowmaster - YouTube

2006 Hummer H3 flowmaster 40series - YouTube

Alpha
HUMMER H-3 with Flowmaster.mpg - YouTube

 

not to be stupid but how are you guys putting these on? you cutting off the old one and clampping the flowmaster on or welding it on? I want to put on on mine but i dont want to cut off the factory put this one on and if something goes wrong with my truck they tell me i voided my warrenty cuz i cut the original off.

 

You can have your exhaust guy weld on a sleeve or transition piece right after the cat so that you can just clamp either the stock setup or aftermarket setup. Personally I'd rather weld it on because once you do anything to your exhaust, you've voided the warranty anyways. Just MHO here, gotta "Pay to Play" so to speak.