Muffler replacement - Diesel Forum

Bob Braam · 07-26-2001, 08:24 PM

Has anyone replaced the existing muffler with a straight through muffler. Looking under the X the factory pipes inlet and outlet pipes are offset. Searching this site I noticed several pickups have done this but I dont know if those pipes are offset. I would prefer the muffler to be 409 stainles steel like the factory system. I would also like a 403 stainles steel 4" tip. Any information woould be greatly appreciated.

bjornar · 07-27-2001, 04:05 AM

I replaced the muffler with a straight DynoMax 17224 muffler.

Raise rear of vehicle about 3 feet (forklift). Loosen right rear shock absorber to facilitate removal of pipe.
Cut right in front and rear of the stock muffler, the new muffler had the same overall length.
Twist the front pipe 180 degrees, so that it goes down 3-4 inches into the muffler instead of up.
TIG weld to front and rear portion of piping.
Replace hangers from orig. muffler to pipe on bend in front of rear axle.

I also replaced the 90-degree outlet bend behind the rear wheel with a straight double 3" out the back. Nice touch...

Tailgate · 07-27-2001, 05:11 PM

Bob:

If you want a "high quality" muffler, I would suggest a Flowmaster. It's not considered a straight-through muffler, but is designed in such a way that it has little to no resistance of airflow.

The problem with DynoMax mufflers is that they are made of tin (or seem to be). You can bend them with your hand in the shop. The Flowmasters are made of stainless steel and are extremely rugged. Call them for an exact model, but would suggest one of their mufflers that have 3.5" in, and 4" out.

I am wanting to put one on my X, but am thinking about also changing from 3.5" pipe to 4" all the way through the exhaust system.

ceferino · 07-28-2001, 01:03 AM

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Tailgate:
... If you want a "high quality" muffler, I would suggest a Flowmaster. ... <HR></BLOCKQUOTE>

If'n you don't mind waking up napping children, rattling windows, and keeping decent folks next to you from hearing their own stereos. I've tried FMs twice now and they were way too loud [img]images/icons/mad.gif[/img] Never again. I use Walker Super Turbos and have never worn one out yet.

Not to mention how loud exhaust attracts the local constabulary... [img]images/icons/shocked.gif[/img]

POLR BR · 07-28-2001, 02:08 AM

The Dynomax Ultra is stainless steel, very heavy, and surprisingly quiet. I recently installed one on my CC expecting some overall increase in noise. In fact, there was no discernable increase at idle or normal running speed. It is only louder, and not by much, when you accelerate hard and the turbo is whining.

tlphlps · 07-28-2001, 01:08 PM

Ditto the Dynomax. Love this muffler. I programmed the engine with the Hypertech months before installing the Dynomax, so I got the opportunity to see how much difference the muffler alone made in power and mileage. A wonderful improvement in power and more mileage difference than the PPIII made, especially towing mileage (increased about 1.5 mpg).

Terry

sail684 · 07-28-2001, 07:18 PM

You have a part number on that Dynomax??? I have the Walker BTM and I'm thinking of going back to stock due to the noise.
Thanks!!!!

ExcursionPSD · 07-31-2001, 04:54 PM

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by sail684:
You have a part number on that Dynomax??? I have the Walker BTM and I'm thinking of going back to stock due to the noise.
Thanks!!!!<HR></BLOCKQUOTE>

Myself and several others have the Walker Big Truck Muffler (#21470 3.5" in/out centered 7" diameter, 30" long body). I do not think mine is much louder than stock, except during cold warmups when the EBV is cycling, giving the 747 jet sound. I think you should check that they did a good job of using sound isolating muffler hangers and that no part of the exhaust system is touching the body or frame.

Good Luck!

BRUTYUT · 08-01-2001, 02:05 AM

I would like to change out my stock muffler to the Walker BTM. Where have you guys that have one got it? Will I need to put in a flex piece of line? If so where is the best place to get me one? and Is it necessary to cut the down pipe or can I add it to the exhaust line by the muffler?
Thank you for the help
Oley

mcadam · 08-01-2001, 02:10 AM

Straight exhaust, only way to go. Loud, but worth it. When I tow past whimpy gassers, worth every penny of taking out the muffler.

ExcursionPSD · 08-02-2001, 04:11 PM

NAPA has them, so does Summit. Since it is longer than the stock muffler, my installer did not need to add any pipe to do the job. I have not added any flex pipe, I have a minor drone at highway speeds, but it is not objectionable, more of a hum.

He did cut the factory tail pipe and exhaust pipe as close to the original muffler as possible.

Bob Braam · 08-08-2001, 08:28 PM

Those of youwho responded to this post I wish to thank you for your help and providing additional "food" for thought. I ended up with the Magnaflow 24" stainles muffler which Iam extremely satisfied with. Now on to the next problem of getting rid of the drone the X has for the past year.

Bob Braam · 08-08-2001, 08:34 PM

I forgot to mention that Dennis with Inovative Truck Products helped me, since he handles both the Dynomax and the Magnaflow. As numerous others have mentioned he is an asset to us power strokers.

AJ'sDad · 08-10-2001, 03:31 PM

I got the Walker BTM. Not too loud, but created a metal-on-metal resonance at idle. I solved it with flex-pipe. Flex pipe also reduced the drone.