Chevy and GMC Duramax Diesel Forum banner
  • Hey Everyone! Enter your ride HERE to be a part of this months Ride of the Month Challenge!

1 - 7 of 7 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter #1
I was wondering what everyone else was getting for city im getting around 13 so i was just curious if that was good... ive heard tire size can change milage but i only have 285/75/r16 on the truck
 

·
Administrator
Joined
·
8,815 Posts
I am getting 16 mpg driving around base and to fairbanks a time or 2. My "city" driving really isn't that. Is your speedo recalled for the bigger tires? if not you need to add 7% to the miles traveled. Also, my numbers are hand calculated.
 

·
Registered
Joined
·
20 Posts
Around the city I get in the low 16's. Last weekend I went up to Dallas and got a calculated 19.1 mpg highway. 20%Bio is generally what I have been running.
 

·
Hi, I'm Earth. Have we met?
Joined
·
3,162 Posts
I get between 16 and 20 depending on driving style and road conditions:D !!!
 

·
Registered
Joined
·
19 Posts
Mine shows 13.2 with my 20" wheels and 33" tires...It was only getting 10-11MPG before I took the lid off my factory air box!

I hand calculated miles traveled before and I was getting 11MPG pulling a car hauler with a fox body mustang on it.

The dealership tells me they can't re-calibrate the diesels. I would like to find out for sure what the truck is getting. Anyone know how to accomidate for the big wide wheels/tires?? I hear they can KILL milage and I just need a little more input on it before I decide what to do about this low milage!
 

·
Administrator
Joined
·
8,815 Posts
you can always buy a handheld programmer and recal your speedo. I know htat 285/75-16 is 7% bigger than the stock tires. Check out this one: http://www.miata.net/garage/tirecalc.html

According to that, if you are running a 305/55-20, your tire is 9% bigger than stock. So, you would add 9% to your miles shown on your odometer and then divide that by the gallons used.
 

·
Hi, I'm Earth. Have we met?
Joined
·
3,162 Posts
you can always buy a handheld programmer and recal your speedo. I know htat 285/75-16 is 7% bigger than the stock tires. Check out this one: http://www.miata.net/garage/tirecalc.html

According to that, if you are running a 305/55-20, your tire is 9% bigger than stock. So, you would add 9% to your miles shown on your odometer and then divide that by the gallons used.

Cool info,thanx!
 
1 - 7 of 7 Posts
Top