My Dealer replaced my trans and then I took my truck from Pa to Va and I went about 240 miles and used a tank of fuel! I have never used so much fuel before. On the trip home I got 14.7 MPG this was better but not the 17 MPG I was getting. The truck ran nice shifted good no slipping. Is my MPG going to get back to 17 MPG ? Why did the MPG drop ? Is there something I can do to get the MPG back?

 

I am the one person that has experienced this problem?

 

Do you know if they flashed/updated your programming? If so they may have goobered something. Most are noticing a slight MPG improvement with the newest flash, but there are cases when the dealer doesn't do the flash procedure correctly and it gets a lot worse.

 

I asked about the program and the Dealer told me if there are no codes there is nothing they can do. The trans is nice but I just do not understand what happened? It has been better after 300 miles but not like it was.

 

There isn't really a break in period with a new tranny. If you're loosing that many MPGs in the tranny it would burn up fast. This is why it sounds like a botched flash.

 

whats your gear ratio? if your truck is your daily driver you might want to gear up your truck by changing your rear end to 3.55 or higher unless you have to pull a heavy trailer every week

my 2 cents

 

I have 33" tires and 3.73 ratio. It pulls a 10,000 lb trailer.

 

oh so you have a decent ratio then i have no other idea to help you out sorry

 

you must have not had it in to the dealership very many times? im guessing this because most people have liked the orig flashes because of power and milage compared to the "updated" flash which robs us of both. I doubt they botched the flash espesially if the only complaint is the milage is down. The truck would run horrid if the botched it.

 

I have never been to the dealer until the trans problem. I have them change the oil that is it. Oh yes inspection also. The truck runs fine!