size change

**custom4584** · #1 (**permalink**) 08-25-2008, 03:40 PM

Just went from a 31" tire to a 34" tire. I'm sure my speedo is off, how do i recalibrate that and do i need to change the shift points of the tranny. Thanks. 03 6.0 auto.

bigd4x4 · #2 (**permalink**) 08-25-2008, 05:59 PM

Quote:

Originally Posted by custom4584

Just went from a 31" tire to a 34" tire. I'm sure my speedo is off, how do i recalibrate that and do i need to change the shift points of the tranny. Thanks. 03 6.0 auto.

I used a superlift truspeed. Works great. If you are going to add a programmer some claim to be able to recalibrate the speedometer. I tried a Edge because they claimed it would work. I even sent it back to the factory for an upgrade but it still had no effect on the speedometer. Before you do anything get or borrow a gps to see if it's off enough to bother with.

**custom4584** · #3 (**permalink**) 08-27-2008, 05:10 PM

Quote:

Originally Posted by bigd4x4

I used a superlift truspeed. Works great. If you are going to add a programmer some claim to be able to recalibrate the speedometer. I tried a Edge because they claimed it would work. I even sent it back to the factory for an upgrade but it still had no effect on the speedometer. Before you do anything get or borrow a gps to see if it's off enough to bother with.

Its off about 6mph at 70. gets worse as you go faster. would the dealer be able to re calibrate it? I dont have a programmer.

iLoveSoccrMoms15 · #4 (**permalink**) 08-27-2008, 05:16 PM

Quote:

Originally Posted by custom4584

Its off about 6mph at 70. gets worse as you go faster. would the dealer be able to re calibrate it? I dont have a programmer.

Yeah, the dealer should be able to take care of that up to a 35" tire. They did mine for free in about 3 minutes with their whatcha-ma-widget. Works great!

Sergio

wyldnative · #5 (**permalink**) 08-27-2008, 05:25 PM

I took my 2000 Excursion to a dealership, and they charged me 70.00 to change the computer settings. I put a 305/70 x 16 on it and the speedo was off by about 9%. They were able to get it changed, and the speedo reads pretty close to right. I have yet to get my truck done, it has 315/75 x 16's on it.

**custom4584** · #6 (**permalink**) 08-27-2008, 05:49 PM

Will they slightly change shift points too? Or just the speedo?

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Remove Advertisements Sponsored Links
Powerstroke.org Advertisement