Flowmaster 70 Series Muffler

Price Paid:  $119.00 from Jegs

Year / Model Reviewed:
1997 Gmc Yukon

Strengths:
Great mellow sound at idle, but growls pretty good when you accelerate. Nice improvement in horsepower at cruising and passing speeds.

Weaknesses:
Not an easy install to the original tailpipe, had to go have an internal sleeve built to make it fit.

Summary:
Great sound, not overbearing at all in the cab, which is good since this vehicle is used primarily for towing. Definite improvement in h.p. from 2-3k rpm's.

Price Paid:  $116.00 from Autopartswarehouse.c

Year / Model Reviewed:
2001 Dodge Ram 1500, 5.9L

Strengths:
Excellent quality product. Good welds, heavy. Nice sound outside the truck.

Weaknesses:
Lots of in-cab resonance at 1800-2000 RPM. Very annoying.

Summary:
Good quality muffler with a nice performance sound. Loud inside the cab. No change in performance or mileage over the OEM muffler.

Similar Products Used:
Flowtech Afterburner, Cherry Bomb, OEM.

Overall Rating
 4 of 5

Value Rating
 4 of 5

Used product for
More than 1 year

Visitors rate this review
5.00 of 5, 1.00 votes

Price Paid:  $115.00 from Gordys

Year / Model Reviewed:
2003 hummer

Strengths:
deep rich sound

Weaknesses:
none

Summary:
I had the 40 series installed and now with help of my new hearing aid I can tell the 70 series is by far my new choice for the 6.0L vortech. It gives that deep low tone at idle, and almost no in cab noise.

Similar Products Used:
40 series flowmaster

Overall Rating
 4 of 5

Value Rating
 4 of 5

Used product for
Less than 1 month

Visitors rate this review
3.67 of 5, 3.00 votes

Price Paid:  $99.00 from Ebay

Year / Model Reviewed:
2003 Flowmaster 70 Series

Strengths:
Great Price on Ebay $99.00 with shipping

Weaknesses:
Drones somewhat. Inside resonance not a plus.

Summary:
This muffler is not loud but drones a little bit in my 2003 GMC envoy 4.2. There was a definite increase in my low end torque and the car takes off quicker. Along with the muffler I have an intake and OEM piping with a bullet performance tip and no back resonator. Many mufflers shops told me that any aftermarket muffler would drone inside due to the fact that GMC's 4.2 engine for envoy is a High Output engine. I had been reading and investigating for a long time on the quietest muffler I could possibly have on my envoy. So I ended up with flowmaster 70 series. The wife thinks it’s a little loud for her. To me all flowmasters are loud. I kind of got use to it. It really gives that deep grumble sound upon acceleration. When cruising its hardly noticeable. If you want quiet keep your OEM muffler.If you want performance be ready to sacrifice sound. At least on the Envoys.If I you don't care about sound or drone get a straight through muffler.

Similar Products Used:
Bullet Performance Muffler

Overall Rating
 5 of 5

Value Rating
 4 of 5

Used product for
1 to 3 months

Visitors rate this review
1.00 of 5, 1.00 votes

Price Paid:  $355.00 from Jegs

Year / Model Reviewed:
1998 Z-71 Shortbed Extended Cab 5.7L

Strengths:
Great sound, noticeable power increase.

Weaknesses:
Not as loud as I was expecting, but the tone is still there. Trust me youll like it!

Summary:
The 70 series American Thunder Exhaust System is actually more than I thought it would be. Besides an awesome sound, the performance gains are pretty satisfying. I noticed a small gain in torque and a definate increase in acceleration and passing power. When they say horserpower gains between 15-20 they arent kidding. I recommend this exhaust to all Silverado drivers.