GT Performance Mods 2005+ Mustang GT Performance and Technical Information

Gear changing and Speedometer recalibration

Thread Tools
 
Search this Thread
 
Old 8/22/05, 06:09 AM
  #1  
Cobra Member
Thread Starter
 
Torrence's Avatar
 
Join Date: January 29, 2005
Posts: 1,450
Likes: 0
Received 0 Likes on 0 Posts
Hi all,
I am hearing everyone talk about 4:10's and all the other gear ratios out there, but I have yet to see anyone say anything about getting the speedometer recalibrated because of the gear swap. I am really considering this, but want to know how much of a pain in the _ _ _ this will be to get it recalibrated. Or will a Diablo do it for you? Has anyone done the swap without a recalibration?

Also anyone heard of 3:90 gears? I heard they are almost up there on the 4:10 level, just not as aggressive. I haven' t seen anyone mention this gear ratio.
Old 8/22/05, 06:42 AM
  #2  
Mach 1 Member
 
Blk'05's Avatar
 
Join Date: February 17, 2005
Posts: 553
Likes: 0
Received 0 Likes on 0 Posts
Im pretty sure this is one of the things your programmer will come in handy for..
Diablo, SCT2.....
Old 8/22/05, 06:44 AM
  #3  
Mach 1 Member
 
Blk'05's Avatar
 
Join Date: February 17, 2005
Posts: 553
Likes: 0
Received 0 Likes on 0 Posts
Ah yes....here you go.SCT features
Old 8/22/05, 06:44 AM
  #4  
Team Mustang Source
 
Ranger's Avatar
 
Join Date: October 1, 2004
Location: Central Virginia
Posts: 1,206
Likes: 0
Received 0 Likes on 0 Posts
My understanding is that the programmer will do it and its a easy fix - if you know the procedure
Old 8/22/05, 09:15 AM
  #5  
Team Mustang Source
 
Scott's Avatar
 
Join Date: August 8, 2005
Location: Georgia
Posts: 255
Likes: 0
Received 0 Likes on 0 Posts
Unless this transmission is a lot different than all the other trannies out there, there is a speedo gear that you change along with the rear end gears to correct the speedo. There are only a couple of bolts that hold the speedo gear in. Easy to do, you just have to know what tooth gear to correct for what gears you put in the back.

Hope this helps.

Scott
Old 8/22/05, 09:25 AM
  #6  
FR500 Member
 
wild stray's Avatar
 
Join Date: September 18, 2004
Posts: 3,108
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by Torrence@August 22, 2005, 5:12 AM
Hi all,
Also anyone heard of 3:90 gears? I heard they are almost up there on the 4:10 level, just not as aggressive. I haven' t seen anyone mention this gear ratio.
Generally speaking, gear ratios run in 5% increments. I know a few people on the board are running 3.90's but they just havn't been as popular as 4.10's and Ford Racing doesn't offer that ratio sale. The ratio is available, I believe thru Motive though.
Old 8/22/05, 09:39 AM
  #7  
 
don_w's Avatar
 
Join Date: June 21, 2005
Posts: 4,276
Likes: 0
Received 1 Like on 1 Post
I have 4.10 gears, as well as taller than stock tires, and used the Diablo Predator to adjust the speedo. It is an easy thing to do.
Old 8/22/05, 12:12 PM
  #8  
GT Member
 
Gnirod1's Avatar
 
Join Date: April 22, 2005
Location: Wheatland, CA
Posts: 126
Likes: 0
Received 1 Like on 1 Post
If you do not have a programmer, I believe that the dealer can reprogram the speedo. Just make sure that the dealer is cool about mods. Mine was cool about it, just put down that "customer claims speedometer is not accurate....check and calibrate". I'm getting an SCT2, just couldn't afford both at the same time. Hope this helps.
Old 8/22/05, 12:18 PM
  #9  
GT Member
 
Gnirod1's Avatar
 
Join Date: April 22, 2005
Location: Wheatland, CA
Posts: 126
Likes: 0
Received 1 Like on 1 Post
Originally posted by Scott@August 22, 2005, 8:18 AM
Unless this transmission is a lot different than all the other trannies out there, there is a speedo gear that you change along with the rear end gears to correct the speedo. There are only a couple of bolts that hold the speedo gear in. Easy to do, you just have to know what tooth gear to correct for what gears you put in the back.

Hope this helps.

Scott
This trans is indeed alot different. There is no need to swap speedo gears like in the past. Calibrating the speedo for different tire sizes and gear ratios is very easy with any one of several aftermarket programmers. The ability for so many things to be changed with a relatively simple (handheld) programmer is one of my favorite things about the new Stang.
Old 8/22/05, 05:10 PM
  #10  
V6 Member
 
2005MineralGT's Avatar
 
Join Date: July 1, 2005
Posts: 57
Likes: 0
Received 0 Likes on 0 Posts
Just to clarify for anyone who may not know, the dealer cannot reprogram the speedometer calibration on these cars as was possible on many of the Fords in the past. Basically, it boils down to the cars being approved for emissions standards with a specific wheel and tire size and specific gearing. Since Ford didn't have them tested and approved with different specifications, the factory computer won't let you change them without the aid of a tuner.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Autotooner
SN95 Mustang
11
11/24/17 12:42 PM
ricky1728
SN95 Mustang
1
2/11/16 07:25 PM
DerekShiekhi
2015 - 2023 MUSTANG
1
9/30/15 06:59 AM
southern stang
Repair and Service Help
1
9/26/15 04:19 PM



Quick Reply: Gear changing and Speedometer recalibration



All times are GMT -6. The time now is 12:22 AM.