scottylucas

After doing lots of researching, I havn't yet found a detailed install walkthrough for the 51" donaldson muffler. This is my first write up so bare with me. I have taken some photos of the install, I have a very small single car garage so space is tight so the photos aren't the best.

First of all the part number of the donaldson M090544. Picked it up at a catepillar for around 80 bucks. The muffler was installed on a 06 quad cab short box, using all the factory 4 inch pipe except for a extra 3 foot piece that I had to buy. 2 Band clamps are required and one standard u shaped clamp.

Tools required; Socket set, pry bars, big hammer, grinder with cutoff disk, welder, Lubricant spray(optional)

First step is to lift the truck, Then attempt to unbolt the factory u bolts pre and after muffler... If they were anything like mine this is where the grinder will come in... Cut them off, you will no need them again.

Next remove all the rubber hangers which hold the pipes and muffler in place, there should be 4, 3 on the muffler and 1 on the tail pipe over the axel. Next twist and wiggle the tail pipe and work the pipes loose, eventually they will come apart, I used a punch and hammer to losen the flange over the join.

Once you have the tail pipe and muffler off, remove the u bolt from the downpipe which is in front of the cat. then remove the pipe and cat. If you wanna keep the cat and at the muffler, skip that step, the donaldson 51 inch may fit in there, I never checked too see if it would.

After you have the cat and pipe removed, place the tail pipe back in place, then place the donaldon up in place, I used a jack stand to hold it up in place while i made adjustments for it to fit perfect.

Next you will need to cut off the pipe in front of the cat which has a slight bend in it, and it will need to be welded to the 4 inch pipe that you bought.

After welding it together (dont worry about how its welded together as long as it is square) measure where the downpipe is to the donaldson intake, then cut your new pipe to that length, dont forget to leave enough to go over the down pipe and go into the donaldson.

After cutting you can test fit it all, you will need too slide the tail pipe back out along with the muffler to get it all to go together, fitting the pipe into the downpipe first. then into the muffler etc.

If your happy with where the muffler sits, and how everything fits, cut the muffler hanger brackets off your old muffler, and you can tack them onto the donaldson. Be sure to make sure the muffler isn't touching any parts of the body or frame to avoid vibration.

After tacking them and your happy with the way everything fits, you can take it all down and weld the hangers on, or leave it up there and weld it there like I did

After its all secured all thats left to do is put your band clamps on over the muffler flanges, make sure they are really tight to avoid leaks. Then add the u bolt clamp to the down pipe, and enjoy!

dodgintrouble

How does it sound? Any sound clips/video yet.
-Eric

AH64ID

Any chance you can shrink the pics? They are much larger than my screen..

Looks good thou, I really like my 40" Donaldson.

cbrahs

i can't see anything but a picture that is 10 times the size of the screen. very difficult to see what is taking place.

scottylucas

resized photos, sounds great, alot like a semi, No diffrence in cab for noise maybe a lil quieter, but outside it sounds awesome, if I roll down the windows, and drive by a object on exaust side, I can hear it nicely, sounds great!

dirtygoat

I hate to be a pain. But could you possibly post some after pics? and sound bit? I have been thinking of doing this for some time and would like to see it installed and the sound it produces.

scottylucas

Sure, forum would only let me post 10 pics at a time,

Youtube Video;

http://www.youtube.com/watch?v=HDZqwucrqTA

Pics;











Sorry about the bad pictures, kinda dark out when I took them, ill try and take more.

CRToney

I have the same muffler and no drone and different sound than stock. I welded stock hangers to the muffler to hold her in place.

Fisherguy

I don't get why you removed the whole exhaust system just to change the muffler?

You replaces the factory off-set muffler with a straight through, what did that do to your tail pipe angle?

scottylucas

once you remove the muffler the rear part of the tail pipe falls down and flops around in the way, there is only one hanger behind the muffler that holds up the tail pipe. I removed everything but the down pipe which joins to the exhaust with a clamp from factory. I didn't keep the cat, thats why I removed it all.

As for the tail pipe angle it is the exact same thing as stock because the straight through muffler is exactly as you said "straight through" I took the factory bend that comes off the down pipe, flipped it around so it bends up instead of down and it lined everything up perfect.

dirtygoat

Thanks for the reply. That was just what I was looking for....

dogescape

do you have pictures of installed and were did you put front muffler hanger