Just bought an 05 4.7. Previous owner had it superchips tuned on the tow tune and speedo calibrated for 285/75/16. He left the tuner under the rear seat but alas 6 months later it isnt there. Dealer seemed sincere when I asked about it but they didnt have it. I advised them that for any vehicle but mine it is just a paperweight. I assume a worker took it.

Tires rub on full lock so gonna change at least the fronts out in a few months as they are starting to show cupping. Probably go back to stock tire size per door label of 255/65/16 especially since I have 3.55 rear end.

What are my options for going back to stock tune? Kinda annoying with the shift rpm's for 1st and 2nd at 3k. Dealer only or would a shop have that function?

What octane is the tow tune for?

Also with the tow tune what function does the factory tow/haul/od off function do?

I searched for these answers for 30 mins but got nothing helpful.

 

Any dealer should be able to reflash your PCM.

As far as the octane, I would assume that it would be a 91 tune, but I don't know.

The factory OD Off switch is designed to eliminate constant shifting while towing in hilly areas, as it causes the transmission to heat up pretty quickly.

 

You are stuck without a tuner. Dealer reflash. Tow tune calls for at least 91 octane. I ran 87 in mine with the tow tune with no ill effects. I loved the extended shift points.

 

Ok thanks for the replies so far. When the front tires wear out or get to bad probably within 6 months I am gonna go back to stock tune and stock tire size of 255/65/16. Might get it reflashed before I go on a 1900 mile round trip in a couple weeks.

Just filled up for the first time today with 87 and I know for a fact that the guy that owned it 6 months total before me even knew it had a tune. I only got the whole story because after I bought it my bro realized he knew the owner who traded it in 6 months before and I could tell from the 1-2 shifting.

Anything particular I should tell the dealer or request when they load a stock tune in? Why do i never see HPTuners mentioned?

Coming from chevy that is all I ever heard/used for the obdll cars. Might go that route seeing as I can tune with it later if needed and use it as a scanner.

 

You probably already know this, but I will say it anyway. If you are 4wd, you can't just change the front tire size. You WILL break something at some point.

 

Very true. Quickest way to destroy a transfer case is to run different size tires on the front.

 

I am 2wd. No need for 4wd. They were cheaper options but the maintenance issues and lower mileage would have quickely cost me more.

I do have the antispin diff which is a nice plus for me.

 

I think you'll be happier with a 265/70/16 tire, which was a stock sized tire.