Redr End Gears Question - Ford Mustang Forum
Like Tree4Likes
  • 1 Post By Sean Reilly
  • 1 Post By XRacer
  • 1 Post By FuelforFire87
  • 1 Post By GrbrBlu
 
LinkBack Thread Tools
post #1 of 6 (permalink) Old 01-09-2017 Thread Starter
Rookie
 
SeaBee0221's Avatar
 
Joined: Jan 2017
Posts: 1
 
Redr End Gears Question

Can anyone tell me why Ford put 3.55 gears n the M/T cars and 3.31 gears in the A/T cars?

SeaBee0221 is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old 01-09-2017
Sean Reilly
Guest
 
Sean Reilly's Avatar
 
Posts: n/a
Because of the different gearing between ( Inside ) the 2 Transmissions themselves.......As FoMoCo Has to Keep the C.A.F.E. (Corperate Aferage Fuel Economy) as Low as they can with ALL of their Cars, (Even then Sports Models) or the Car could fall below the threshold for the "Gas Gusselers Tax" if it does NOT meet a certain MPG For City/Highway.......And dont forget, the 3.31:1 is the Maximum Performance Gear that Ford Offers in the 2 Pedal (Auto) Stang. .....And a 3.73:1 is the Maximum that you can get (Order) in the 3 Pedal GT's
Short answer, of course!.


Sean.

5.0 Coyote likes this.
post #3 of 6 (permalink) Old 01-09-2017
SHELBY GT 350 Member
4.6L Member
S197 Member
 
JBert's Avatar
 
Joined: Jan 2011
Location: Central Massachusetts
Posts: 9,165
           
I thought the manuals came with 3.31's as standard equipment; other ratios available as options?

| 2010 GT coupe | Daily Driver with some Steeda and GT500 take-off stuff for the occasional track day
JBert is offline  
 
post #4 of 6 (permalink) Old 01-09-2017
PONY Member
 
XRacer's Avatar
 
Joined: Aug 2014
Location: Percy
Posts: 326
 
You're correct 3.31 is standard in 5.0 manuals. 3.55 & 3.73 are optional. In so far as I know if you order 3.73's you also get the torsion diff. Normally 3.31 & 3.55 come with a standard clutch type limited slip. The standard limited slip is probably better for drag racers although really serious drag racers will want a spool. The torsion is preferred by autocrossers and road racers. IMO the 3.55 is the "Goldilocks" gear. The MT82 used in six cylinder cars has shorter gearing than the V8 models hence no need to offer anything shorter than 3.31 in those cars.
dusman59 likes this.
XRacer is offline  
post #5 of 6 (permalink) Old 01-09-2017
PONY Member
 
FuelforFire87's Avatar
 
Joined: Apr 2011
Location: Lombard
Posts: 412
 
Actually the Auto only comes with 3.15 rear gears. The 6R80 has a really steep first gear so it can still get off the line quickly and the tall rear gear (numerically lower) helps with highway fuel economy. Most would agree that this setup is pretty much optimized from the factory and swapping to a higher gear like 3.55 or 3.73 will actually slow down your quarter mile time. If you want to be faster in the 1/4 its better to invest in a torque converter than a gear swap.
noldevin likes this.

2014 Mustang GT 6R80, Procharger Stage 2 D1SC, BBK 85mm TB, Boss IM, Sai Li fuel system. Circle D 3C, 1-7/8" Kooks Long Tubes w/Offroad X Pipe, Lethal Over-Axle Pipes, Corsa Quad Axle-Back, Eibach Pro System Plus, BMR K member, Shaftmasters DS, Forgestar CF-5 Wheels and Nitto NT05 tires. Lund Tuned

Lots of suspension goodies and some other stuff I can't remember.
FuelforFire87 is offline  
post #6 of 6 (permalink) Old 01-10-2017
Apprentice
 
GrbrBlu's Avatar
 
Joined: Sep 2013
Location: Central
Posts: 185
 
Quote:
Originally Posted by XRacer View Post
You're correct 3.31 is standard in 5.0 manuals. 3.55 & 3.73 are optional. In so far as I know if you order 3.73's you also get the torsion diff. Normally 3.31 & 3.55 come with a standard clutch type limited slip. The standard limited slip is probably better for drag racers although really serious drag racers will want a spool. The torsion is preferred by autocrossers and road racers. IMO the 3.55 is the "Goldilocks" gear. The MT82 used in six cylinder cars has shorter gearing than the V8 models hence no need to offer anything shorter than 3.31 in those cars.
3.73s were also a separate option for manual transmission GTs; that separate option came with the TracLoc differential. The only way to get a Torsen on a GT from the factory was with the '13-'14 Track Pack option.
noldevin likes this.


'14 Grabber Blue GT - Base 300A, Track Pack, Recaro seats - Mods: SCT X4, BBK long tubes and X-pipe, Roush axlebacks, MGW shifter, BMR LCAs and UCA w/ mount
'93 Reef Blue LX 5.0 - 5-speed, black interior, factory A/C delete - GT40P Top End, 5-Lug/4-Wheel Disc - SOLD
GrbrBlu is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ford Mustang 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, otherwise you will not receive the necessary confirmation email needed to confirm, validate and activate your new AFM member account.

Failure to provide a VALID email address, will result in the cancellation of your new AFM member account registration.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 Off
Pingbacks are Off
Refbacks are On

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


Search Engine Friendly URLs by vBSEO 3.6.1