I want to install a magnaflow muffler on my 99 burb and then finish out with new pipe from there since the OEM tailpipe is 2.75". Magnaflow has 3" mandrel bent universal tailpipes. They list one part # for 96-98 and another part # for 99-03. I am confused in that a 99 has the same body style as the 96-98s. "Just Magnaflow" suggested that the listing was for pickups, not suburbans and wasn't sure what to tell me. They suggested I call Magnaflow directly to ask about this. Magnaflow suggested that the 96-98 would probably work but might need modification. Does anyone here know what the difference might be between the chassis on the 99 sub and the 99 pickup? Which one should I use?
Thanks!

I'd just get the flowmaster universal 3" tailpipe kit and then you can have it any way you want it.

Thanks, FF I'm already aware of the Flowmaster tailpipe but I was looking for a cleaner installation. The Flowmaster tailpipe is four individual pieces vs the one piece Magnaflow. I want to use the stainless band clamps as much as possible and that would mean having to buy three more of those. I might end up using the Flowmaster kit if I can't get a definitive answer concerning the Magnaflow. I'm certain someone can tell me if the 98 burb is the same or different than the 99 burb or the pickup and which pipe will work.
Thanks

Muffler? How 'bout straight pipe that puppy? Turbo knocks down a lot of the noise. I guess it depends if it's your daily driver/family vehicle....

Muffler? How 'bout straight pipe that puppy? Turbo knocks down a lot of the noise. I guess it depends if it's your daily driver/family vehicle....

Huh?....What's that you say??....Turbo doesn't reduce noise enough on a suburban. Partial throttle resonance is intollerable at times.

Ax Subman, please tell us how you like the praise dyno brakes and gear vendors OD

OH, OKAY....I GOTTCHA..... that's why I said it depended upon if it were a family/daily driver....some like the fun, and some don't.

They list one part # for 96-98 and another part # for 99-03. I am confused in that a 99 has the same body style as the 96-98s.

This is because 1999 was a model year changeover. There were two '99 models: old body style, and new body style. 1999 was the first year for the new body style (technically they were 2000 models that were built in 1999, but some parts vendors like Magnaflow get them mixed up and call them 1999's, when they're really 2000's), which is the same as what is currently sold in the '05 models, soon to be replaced by the new GMT-900 trucks.

All of the 6.5 diesels were the old body style - the 6.5 diesels never made it into the new body style. So, the old body style 1999's were the exact same as the '96-'98s, so go with the part # for the '96-'98 and it will fit fine.

I'm not sure when the new body style began production in 1999, but mine is an old body style '99 with a build date of 8/98.

Hope this helps. Let me know how the exhaust install goes - I'm looking to do the exact same thing. How do you plan to attach the muffler to the mid-pipe with the flange where it bolts to the turbo downpipe? Are you getting rid of the cat/soot trap?

OH, OKAY....I GOTTCHA..... that's why I said it depended upon if it were a family/daily driver....some like the fun, and some don't.

Truth be told, mine's the family car. I'm seriously thinking about adding a kitty and or a banks muffler. I'm guessing a side effect of the cat will be slightly less noise. Anyone have an opinion on this?

Joispoi, leave the cat out. They are called a "soot trap" for a reason. A good muffler will acheive the results you desire. A friend of mine has a 95 like mine with the same exhaust but his wife wanted it a bit quieter, so he had a flowmaster put on and it is really quiet now, kinda stockish, but with a nicer tone. He has guages and didn't notice any appreciable difference in egt either.

Thanks Stingray, that's the scenario I assumed. I think I'll go ahead and order the 96-98 tail pipe but I haven't decided which Magnaflow to get. They make the aluminized straight through 3"x6" muffler in 14", 18", and 30" body lengths. I've researched this for hours on the web looking for different opinions of what sounds good or bad on an otherwise stock truck with a modified factory exhaust. As you are probably all aware, the opinions run from one end to the other. I'm not looking to blow anyone of the sidewalk, I just want to add a little "tone" to my truck and maybe a little whistle while lowering my EGT and maybe picking up a mile or two in milage. On some days I'm thinkin' 14", on others I'm thinkin' 30". I might split the difference and go with the 18". (Ask me again tomorrow and see what I'm thinkin' ;-)

I was originally saving my pennies for JK's exhaust but decided (at least for now) to take the poor man's approach. I'm going to cut the pipe just ahead of the cat where it's an even 3" and go from there. The down pipe in my '99, as one or two others have mentioned, ain't pretty but it doesn't look like it was run over on the expressway like the older ones, so I will leave it for now.

The 14" Magnaflow is about $66 and their universal tail pipe is about $52. A short piece of 3" pipe, three band clamps, and a couple home made hangers sounds like a worth while little project.

guybb3,
My Praise Dyno brake's were a kit. Front cryo rotors with pads, rear shoes and spring kit. At the time I reused my calipers and had the drums turned. I have since changed out the calipers since a pulling issue I had didn't go away with the upgrade. I also changed over to NAPA ceramics pads to reduce the dusting I was getting from the PD pads. Stopping power was much improved overall. The old brakes used to fade very badly. It's been over 50k miles with this setup now and the front's have been pulsing for a while now. For the PITA that's involved in getting the rotors off these trucks I will probably go back in with new cryo's and not bother to have these turned. I may go with Baer this time just for the heck of it. I know Power Slots are very popular but I don't think they are cryo treated.

I put the GV in just this last May. I bought it used from a member of the page site....Absolutely Love It! Much quieter while driving at highway speed and I can keep up with the rest of the world. Best previous milage was 17. My best since is about 18.6mpg, loaded for vacation (not towing), part of it through the smokies at 75mph average but with the AC off while it was only about 70 degrees out, (front windows only cracked about 2") I think part of this "best tank" may have also been due to the cool outside air and of course not having the load of the ac on. Since the installation I have a slight drive train vibration between 45 and 50 mph, noticable but not too objectionable.
See Ya's

The Tire Rack just came out with cryo treated powerslot rotors and my fronts nead to be replaced badly. I think I'l go with those and a set of Hawk brake pads.

I was originally saving my pennies for JK's exhaust but decided (at least for now) to take the poor man's approach. I'm going to cut the pipe just ahead of the cat where it's an even 3" and go from there.

Oh, so it is a normal 3" pipe ahead of the cat? That would be great if it is so I don't have to mess with the flange piece on the mid-pipe from the downpipe. Just cut it there and slip the new muffler on the old mid-pipe, and clamp it. I know the stock tailpipe is 2.75" (which no one makes pipes that size aftermarket), and the mid-pipe seemed to vary in size and shape (looks almost oval) right behind the downpipe bolt-on flange. It looked relatively normal by the time it got to the cat, but wasn't sure what size it was. If its a regular 3" O.D. pipe there, then a 3" I.D. muffler should slip right on it. That would be great! Anyone done that?

The down pipe in my '99, as one or two others have mentioned, ain't pretty but it doesn't look like it was run over on the expressway like the older ones, so I will leave it for now.

I think they are all bent and dented - that was the only way the factory could get the bends in the pipe without mandrel bending them. They seem to be smooth on the bottom side (the side you can see from underneath), but the top sides are where they look like they were run over on the expressway. I would be willing to bet if you took your downpipe off, you would find all the dents on the top side of it.

I also started this same thread on the page. I only recieved one response but it was from a fella that did this same thing except he adapted to his original tail pipe. He used a 3x24 Summit Racing glass pack and he says it isn't very loud at all. He said the 3" muffler slipped right over the mid pipe.

The problem isn't with the way they bent the pipe but the fact that the downpipe is installed before the motor is put in the engine bay at the factory.

I ordered the Magnaflow tailpipe and their 18" muffler. I'll let you all know how it goes in and how it sounds.

Well...everything but the tailpipe came in just a few days. The tailpipe was to be drop shipped directly. A few days past so I called only to find that Magnaflow was out of stock and it was back ordered. They estimated about two weeks. So I called again last week and they were still out of stock and suggested it might be another two or three weeks. So I bailed on the Magnaflow and ordered the Flowmaster universal tailpipe from Summit. It's more pieces and cost a little more with having to buy more clamps but I was tired of waiting. The Flowmaster kit came yesterday. I might get to the installation tomorrow night.

Still like the gear vendor od?

I "Got er dun" tonight. I had enough pipe and so I was originally going to experiment with straight piping it but I was in a hurry so I didn't mess with it. I had to cut all four pieces of the FlowMaster tail pipe kit, there is plenty of pipe there. I made my own factory-like hangers using 1/2" bar stock and a torch and bolted them to regular muffler clamps. I "cherried" one end of the bar stock with a torch, flatened it with a hammer and bolted this flat end to the clamps. I then "cherried" and bent the bar stock into what ever shape hook I needed to hang them from the original factory rubber hangers.

This setup added just a little V8 burble which is very noticable when I first fire it up (expecially in the garage), but there is almost no difference at idle. The burble is also noticable at any cruzing speed but there was no drone at all at any highway cruzing rpm. The burble is definantly there but in no way objectionable. With the windows open I can hear the turbo wind down after burping the throtle but then again I could hear this with the stock exhaust as well. While the increase in exhaust sound is just noticable inside the burb my son said he could definantly hear a big difference when I pulled away from the house. This was the 18" muffler and I think I could have easily gone with the 14". I actually hope the muffler burns in a little and gets just a little louder.

And Yes, I still love my GV.

Thanks for the update. Sounds like a good setup. Got any pics?

I guess if you want it louder, you could always straight pipe it. I assume you got rid of the cat, right?

Did you replace the downpipe?

Also, let us know if you see any MPG improvement.

Can you feel any power difference?

When I did my 94 I noticed about 2mpg increase. It was straight piped with a BD downpipe though. It was noticeable, especially in throttle response and it may have been the mental horsepower being staight piped):h but it felt like there was an improvement in passing power too.

This was a "cat back" exhaust mod. (from the north end of the cat ;) ) So far I agree that you really haven't done that much til ya upgrade the down pipe. Time will tell.