Doug Thorley Diesel Cat Back Exhaust System

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Features

  • The Doug Thorley Diesel Exhaust System juices-up Powerstroke, Duramax and Cummins diesel trucks with free-flowing power
  • Utilizes custom CNC mandrel-bent 16-gauge aluminized steel tubing to eliminate restrictions and backpressure
  • Doug Thorley Diesel Exhausts boast a massive 4" pipe diameter to accommodate high-displacement diesel engines
  • Bolts directly to stock mounting positions at the turbo or catalytic converter without any modifications required
  • Doug Thorley Headers' Diesel Exhaust Systems employ factory-style hangers for straightforward mounting
  • Exit pipes are capped-off by a whopping 5" chrome exhaust tip
  • Includes a high-performance Thorley muffler
  • Your Doug Thorley Diesel Exhaust carries a Lifetime Warranty for the original owner

Description

Your diesel rig came with more than enough horsepower and torque for the average driver. Doug Thorley Exhausts have never been much for average, though. Their decades-long mission has been to make stock exhausts look inferior.

This is where Doug Thorley Headers’ Diesel Exhaust comes in for your truck. Using 16-gauge aluminized steel tubing in a girthy 4” diameter, custom CNC mandrel bending and a free-flowing muffler, a Thorley Diesel Exhaust adds instant punch at the pedal. It provides loads of low-end pulling torque, too.

Doug Thorley Diesel Exhausts keep installation simple. All diesel exhausts mount to the original positions, and include factory-style hangers for straightforward mounting. Plus, each Doug Thorley Diesel Exhaust stays 50-state smog legal.

To top it all off, your Doug Thorley Diesel Exhaust is capped by a burly 5” diameter chrome exhaust tip and carries a Lifetime Warranty for the original owner—hardly an average deal on diesel exhaust.

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99 dodge cummins

Posted on 10/22/2007 by Rick L G. (Harrison,AR)

1 of 1 people found the following review helpful.

"I ordered the Doug Thorley turbo back 4 in. exhaust, but it was back orderd twice from the factory which was 4 week delay. I recieved instead was the Jardine exhaust . I,m happy with it . Seems to be a Quality product. Installation was real smooth and all the OEM hangers fit good. Has a real nice chrome tip and has a real nice throaty sound. It took me less then 3 hr. to cut off old and install the new exhaust in my driveway by myself. I beleive it was a good purchase and worth waiting for."

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Easy Installation

Posted on 04/18/2007 by Jeremy H. (Mcveytown,PA)

1 of 1 people found the following review helpful.

"The kit was very easy to install. I am happy with the sound!"

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OK

Posted on 04/13/2007 by James M. (Carbondale,KS)

"I ordered the Doug Thorley exhast, but the jardine exhaust was what I got. the picture was bolt up but this system was cut and weld. It did go on and seems to fit."

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Excellent

Posted on 04/06/2007 by Randall H. (Montague,MI)

"System was VERY easy to install. I suggest using a sawsall to remove the stock system in three pieces. I removed the stock, installed and welded the new, in 1 1/2 hours! Excellent system, sounds AWESOME! Really brought the 7.3 to life!"

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doug thorley diesel exhaust

Posted on 04/04/2007 by John B. - 1996 Ford F-350 (Mount Morris,MI)

"for money, the best value diesel performance system available. as good as systems costing twice as much."

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About John B.
Vehicle
1996 Ford F-350
I use my vehicle for
pulling a wedge three car trailer.
 
Great System

Posted on 03/10/2007 by James S. (Grand Bay,AL)

"The system sounds just great, can't keep my foot out of it enough to tell if it has helped my fuel mileage. The truck seems to have more power, I haven't towed a large enough load yet to really evaluate the pwer part of it. Being an old school hot rodder, I'd buy it again just to be able to listen to the pwerfull sound of it, I really enjoy it. Thanks"

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Wasnt so simple. But worth it.

Posted on 01/31/2007 by Alex M. (Carthage,MO)

"Well the shipping came in on time as promised. Everything was there, no missing parts. I have basic knowledge of mechanics but the instructions were not very clear at all. I have a 2002 Excursion Limited Diesel, I would have to say that the biggest problems with this were getting the rubber hangers of, and the down pipe would not come out at all. It will have to be hacksawed or you will have to remove the peice holding the transmission up to provide enough clearance of the downpipe removal. Also you will need to have a high jack or the cat back will not have enough clearance to be removed, but it can be hacksawed. All in all, if you can manage the removal of the old muffler, putting the new one will be much much easier. I hope this helps."

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Powerstroke

Posted on 01/14/2007 by Courtney D. (Fort Mill,SC)

1 of 1 people found the following review helpful.

"Great sounding diesel exhaust nice and throaty without being too load. Easy to install hardest part is getting the old system out."

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About Courtney D.
 
great sound

Posted on 10/15/2006 by Heath P. (Mesa,AZ)

"I was leary about getting a cat-back system, but w/ the new emissions in 2007 I had to keep the cat on. The system is very easy to install. The hardest part is getting the old system out. It's not too loud but gets you noticed. I only wish the tip was longer, it looks kind of funny with big exhaust and this short tip. Overall very satisfied with my purchase. The truck runs great and sounds great now. I did get better response with it also."

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PUREPOWER1

Posted on 10/05/2006 by Ted M. (Ankeny,IA)

"I HAVE 06 F250SD SCAB WITH 6.0L POWERSTROKE DIESEL AND PUT 4" CAT BACK EXHAUST AND HAVE K&N COLD AIR INTAKE. I LIKE THE SOUND OF IT AND NOT HUGH IMPROVMENT IN POWER BUT I DO SEE A LESS IN MY TURBO OUTPUT. WHEN I AM PULLING MY 33FT CAMPER TRAILER. IT HAS FACTORY BOOST GAUGE IN IT. OVERALL PRETTY HAPPY!"

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About Ted M.
 
Nice Exhaust

Posted on 09/17/2006 by Jason D. (South Jordan,UT)

"Very easy to install. Great exhaust for the money. Helps my diesel breath better."

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About Jason D.
 
diesel exhaust

Posted on 09/09/2006 by Brandon C. (Phelps,NY)

"the ease of instalation was amazing! great sound and loads of power.feel the difference of torque.Totally happy!"

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About Brandon C.
 
firecat

Posted on 07/08/2006 by Richard E. (Galloway,NJ)

1 of 1 people found the following review helpful.

"Love the cat back 4"exhaust system. I installed it in 1&1/2 hours that is removing old exhaust first.The next day we left for Florida,I gained 4&1/2 miles to the gallon with no other changes to my chevy.Thank You Rick."

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99 Ram Diesel

Posted on 06/22/2006 by Eric R. (Brush,CO)

"The sound is awsome and noticed the extra power right away. It only increased mileage 1MPG."

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About Eric R.
 
Thorley know how

Posted on 05/31/2006 by James M. (Carlotta,CA)

"The turbo back system fit near perfect. Haven't had it long enough to judge milage however did up the power just as promised. If I had a complaint it would be the instructions either left something to be desired, or I did not receive complete instructions. Still it was easy enough for even me to figure out. Thorley enginuity made a nice looking professional job on my diesel pickup. Everything was bent or shaped just in the right spot to make the job look professional even though I did it."

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About James M.