Aftermarket wheel computer/warranty and fuel question - Ford Powerstroke Diesel Forum
User Tag List

 
LinkBack Thread Tools Display Modes
post #1 of 6 Old 05-10-2010, 08:17 PM Thread Starter
Powerstroke.org Rookie
 
Join Date: Dec 2009
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Aftermarket wheel computer/warranty and fuel question

Hey there. I recently upgraded from my factory 17" sport rims with 265/70/17 to raceline renegade 8's with nitto terra grapplers 285/75/17's. I have not done any mods to the computer after adding the new wheels/tires. Does the computer upgrade make that big a difference. How do I go about changing it? Also if I take my truck in for warranty work, something trans related with the aftermarket rims void the warranty? My fuel mileage is suffering big time. Im averaging 10.4 on highway compared to around 15 with the smaller rims and tires. As you can see im new here, is there any warranty friendly mods to improve mpg's, or atleast a mod that can be hidden, maybe just a tune? Thxs
NVR ENUFF is offline  
post #2 of 6 Old 05-11-2010, 01:43 PM
Compression Ignition Addict
 
pistolpete837's Avatar
 
Join Date: Sep 2006
Location: Bear Creek,NC
Posts: 929
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Send a message via AIM to pistolpete837
Is that mileage drop hand calculated, or the dash read out? You should not have that bad of drop with those tires. I have the 285/65/18 Terra Grapplers with stock rims, and am getting 15mpg mixed driving. Your warranty SHOULD be fine, but the dealer can always try to be an a$$ about things. Tuners such as SCT, H&S, Spartan are supposed to be undetectable to the dealership. A tune combined with an DPF/DOC delete should get you in the 18 mpg range.

Peter
2008 F-250 XLT FX4 SuperCab ShortBed
H&S Mini Maxx, DPF/DOC Delete, AFE Intake, Airdog, Terra Grappler
556 HP 1059 TQ

Farm Truck
2006 F-250 SD SC LB FX4, B&W turnover ball, Durabak liner, Cobra CB, cat delete
pistolpete837 is offline  
post #3 of 6 Old 05-11-2010, 09:44 PM Thread Starter
Powerstroke.org Rookie
 
Join Date: Dec 2009
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Thats with the dash read out. I am kind of new to all this computer controlled stuff. Everyone around me says updating to match the tires is a must. Does it really make that big a difference? What changes? Shift points? What else??? Thxs
NVR ENUFF is offline  
post #4 of 6 Old 05-11-2010, 09:47 PM
Compression Ignition Addict
 
choupique108's Avatar
 
Join Date: Jun 2008
Location: Lake Charles, Louisiana
Posts: 3,398
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 0
Thanked 2 Times in 2 Posts
Feedback Score: 0 reviews
you didnt upgrade enough tire size to make a difference in anything.

1997 Single Cab Dually, S366 w/ Irate mount and plenums, EFuel, Intercooler, P.I.S 175/80s, Corbeau seats w 08 console, 19.5s, 6637, Black Interior with swede headliner and visors, Custom badges, Flight Fab Traction Bars.
choupique108 is offline  
post #5 of 6 Old 05-12-2010, 05:16 AM
Compression Ignition Addict
 
pistolpete837's Avatar
 
Join Date: Sep 2006
Location: Bear Creek,NC
Posts: 929
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Send a message via AIM to pistolpete837
Im not sure wait your referring to with the "computer", but you are fine, no other mods are needed. The first thing I would do is hand calculate your mileage, and see where you stand.

Peter
2008 F-250 XLT FX4 SuperCab ShortBed
H&S Mini Maxx, DPF/DOC Delete, AFE Intake, Airdog, Terra Grappler
556 HP 1059 TQ

Farm Truck
2006 F-250 SD SC LB FX4, B&W turnover ball, Durabak liner, Cobra CB, cat delete
pistolpete837 is offline  
post #6 of 6 Old 05-12-2010, 05:33 AM
Compression Ignition Addict
 
jimd1050's Avatar
 
Join Date: Feb 2009
Location: Plainville, MA
Posts: 283
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Thanks: 1
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Cool Tire Diameter

The taller tire will show that you've driven less miles than you've actually driven. That alone will make your hand or computer calculations wrong. The 285/75's are 33.9" and the 265/70's are 31.5 - that's 2.4" difference in diameter. Your stock tires yielded 640 revolutions per mile and the new ones yield 595 revolutions per mile - that's significant! I had Ford plug in a new number when I bought my 35's - there were three places where it had to be changed. One for the transmission computer, and two places in the main computer. One fixes the speedometer/odometer, one adjusts the braking force for the taller tires. They charged me 1/2 hour to do it.

Regards... Jim D

'08 F250XLT Super Duty 4X4
Intake, Tuning and Exhaust... Back to Banks
Suspension/Drivetrain by WC Motorsports

http://www.justtruckin.net/pages/mytruck.html


Last edited by jimd1050; 05-12-2010 at 06:20 AM. Reason: More info
jimd1050 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome