My cat just went missing and a magnaflow ended up in it's place. At first it seemed like the truck was actually down on power and I had to work it harder, after driving it about a hundred miles it's back to stock and just keeps getting better. Mileage is up and the truck just seems to run smoother, is this normal or did something else happen to mess with my truck and it was just a coincidence?

Just for comparison's sake the truck is barely any louder than stock, you can hear the turbo a bit more but when cruising you can't tell any difference. I still have the stock muffler though, that's next on the list. Driving the same route to work mileage seems to be up about 1.5mpg already but it's only been on a little over 100miles so I'll report back when more time has elapsed. There is less smoke than before, which I'm not super happy about but will fix later, so it must be flowing more air to clean the exhaust up since the cat isn't doing it any more. I'm getting a Aeroturbine 4040XL to replace the stock muffler and a smarty Jr to help with the smoke situation.

 

I removed my cat when I installed the 5" exhaust kit. I was expecting an improvement in mileage but I haven't seen much yet. With the cat removed I do have the diesel exhaust odor again.

 

There is no sensor after the turbo, so I would have to say no, there is no computer adjustment.

On second thought, if the engine is moving more air, or more efficiently, the mass air meter would see it, and the computer would adjust appropriately. Exactly what, I don't know.

Tony

 

it is just your imagination. what 08 parts did you put on your truck

 

My cat blew out it's insides somehow, and I put on a MBRP straight threw muff., and still can't hear much for exhaust sound. I think a straight pipe next might be the ticket instead of the mbrp. muff., wish I knew it before a spent the money, and the effort with the mbrp..

 

The computer does learn your driving habits, so I'm told, so it could take a while for it to adjust.

Take the cables off for about 30 minutes, and ground the system out by pressing the brake/turning the key on/turning the lights on/ something to that nature... then hook them back up. Supposedly, this will reset your ECM... I'm not exactly sure how factual that is, but I have heard it works. Can't hurt anything besides your presets...

 

I was aware that the Tranny relearns your habits, takes about 1500 miles IIRC.

 

i put on a 5" flo pro with muffler, no cat. mileage went up 1 mpg. power seems good. 06 mega 4x4, bully dog on 75 hp, 33" tires, 3.73's. getting 17 mpg's.

 

I might try resetting it but it works great now. I just drove almost 1900 miles from Texas to northern California and I think the biggest thing the truck needed was just get out and get run for a while. The first tank, mostly cruising between 70 and 75 got me 15.4mpg, the second tank was going 75-80 and got me 18.5mpg. The rest of the trip has been between 17.9 and 18.9mpg depending on speed and terrain. I'm going to get the Aeroturbine put on while I'm out here so we'll see if there is any noticeable gain on the trip home.

I have all the '08 steering stuff and the '08 driveshaft. It steers very nicely now and is extremely easy to drive. I would suggest it to anyone that is doing any front end work.