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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

3.90s - Do they exist?

  • Thread starter Thread starter apk1971
  • Start date Start date Jun 9, 2004

apk1971

New Member
Jul 28, 2003
133
0
0
Upstate NY
Jun 9, 2004
#1
  • Jun 9, 2004
  • #1
Looking for a gear between 3.73 and 4.10s for my '03 GT. I read someone had hem but do not recall where. Does anyone know if they are available and where they can be purchased?

Thanks!
 

Dark Knight GT

I can't get it up......ok that didn't sound right.
May 26, 2003
3,653
2
56
Ozark, Missouri
Jun 9, 2004
#2
  • Jun 9, 2004
  • #2
I believe Pro5.0 gear and Motive Gear both make 3.90's. Not aware of where to buy them though. Might want to do an internet search for Motive Gear and Pro5.0 gear.
 
D

Daves4.6GT

New Member
Sep 17, 2003
163
0
0
Jun 9, 2004
#3
  • Jun 9, 2004
  • #3
Sounds like a good choice........Im sure there are pelenty places you can find them.......

Dave
 

SonicBlueBabe

New Member
Sep 20, 2003
289
0
0
Boca Raton, FL
Jun 10, 2004
#4
  • Jun 10, 2004
  • #4
I got mine from Pro5.0 Great choice BTW!!!!! I was also deciding between the 3.73's and 4.10's, and I saw these. They are perfect, I love them!
 
H

HogStang

New Member
Mar 25, 2004
193
0
0
Jun 10, 2004
#5
  • Jun 10, 2004
  • #5
I've got an Automatic and I went with the 3.90's, actually glad I did now that I'm goin blown.
 
M

millatime

New Member
Oct 23, 2003
370
0
0
Palm Harbor, FL
Jun 10, 2004
#6
  • Jun 10, 2004
  • #6
www.mustangtuning.com sells the motive 3.90s
 

decoy562

New Member
Oct 9, 2003
1,526
0
0
Acworth, GA
Jun 10, 2004
#7
  • Jun 10, 2004
  • #7
They exist, but they are not a ratio that was offered by Ford.
 

apk1971

New Member
Jul 28, 2003
133
0
0
Upstate NY
Jun 10, 2004
#8
  • Jun 10, 2004
  • #8
Thank you for the direction...

1 other question, since this is not a ratio not offered by ford, will I have problems finding a speedo calibrator to compensate for the 3.90 gears?
 
B

blockhead

New Member
Feb 24, 2004
69
0
0
Jun 10, 2004
#9
  • Jun 10, 2004
  • #9
They do exist and your on the same boat i was in. i was looking for the same thing and did allot of research here. This is what i came up with. I’m sure somebody will correct me if I’m wrong.

Ford Racing gears are the best. They don’t offer 3.90 why i have no clue.

Motive and any other gear making company seems to use softer metals. This is a controversy subject. Seems like a good chunk of people seem to think that way and others fight the argument.

People with 3.90 seem to be happy but some do complain about rear end noise. i strongly believe that the 3.90 is a happy medium between 3.73 and 4.10. With a good pro mustang mechanic shop and not your local general mechanic shop will make a world of difference when it comes to keeping the gears quit and running good. After all your torque goes thru them.

I’ve also come to a conclusion that if you think ahead about what is your ultimate goal that you will only do things once. Especially since mechanic rates for a good pro shop are not cheep.

If you plan to go with charger like vortech, procharger, paxton or any turbo. that you’ll be fine up to 3.90 for highway use. They might be a little high on rpms depending at what speed you like to drive in the highways.

If you decide on a kenne bell personally by far the best or a Eaton you will have to cut back on the 3.90 and go with 3.55 or 3.73. Because the twin screws seem to kick in hard from idle to redline and usually more expensive than the others.

This is another controversy subject and i don’t mean to piss anybody off with any of these great power adders. Again im not speaking from experience just from what I have read.

Good luck I hope this helped.
 

MineralG2k2GT

New Member
Feb 9, 2003
451
0
0
Lowell, MA
Jun 10, 2004
#10
  • Jun 10, 2004
  • #10
Dallas Mustang's Speedcal will solve your calibration problems...

www.dallasmustang.com

 

Turbo92PGT

Member
Feb 17, 2003
746
0
16
Auburn Washington
Jun 10, 2004
#11
  • Jun 10, 2004
  • #11
I'm trying to find out what gearing I should put in my car. I'll probably just get some 3.73's because I have heard great things about Ford Racing gears. I'm going to be running some kind of nitrous kit on my car in the future, so I dont want to just spin the **** out of the tires. So 4.10's maybe arent a good choice for me, I really dont know though. Not very experienced with it
 

mogs01gt

Founding Member
Jul 22, 2002
3,113
30
119
Ohio
Jun 10, 2004
#12
  • Jun 10, 2004
  • #12
yep I got Pro 5.0 3.90 gears. I love em
 
G

GinoGT

Founding Member
Aug 11, 2002
1,862
0
36
Jun 10, 2004
#13
  • Jun 10, 2004
  • #13
The only reason 3.90 gears exist is so 4.10 and 4.30 gears have yet another ratio they can beat the crap out of.

N/A, 4.10 or 4.30, period. Fear of the gear should be immediate grounds for revoking the privilage of owning a Mustang.
 
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