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URGENT: Speedometer gear

  • Thread starter Thread starter Fopar
  • Start date Start date Aug 1, 2007
F

Fopar

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Apr 1, 2007
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San Marcos, CA
Aug 1, 2007
#1
  • Aug 1, 2007
  • #1
Hey guys just finished a gear swap from 2.73s to 3.73s, obviously the speedo is way off. Does anyone know what speedometer gear (VSS gear) count i'll need for the new combo? Tires are 245/45 R17s. I need to do this today and the ford dealership closes at 5 (less than 2 hours).
 

The Green GT

No 13 year olds are safe around me.
10 Year Member
Jan 8, 2006
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Aug 1, 2007
#2
  • Aug 1, 2007
  • #2
I dont know if a dealership will have them. But I used a 23 tooth white gear when I went to 3:73's.

I got mine from www.50resto.com
 

Dino Dino Bambino

15 Year Member
Jun 13, 2007
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Cyprus
Aug 1, 2007
#3
  • Aug 1, 2007
  • #3
I used the 23 tooth black speedo gear for my automatic. It still leaves the speedo reading ~6% too fast but that's acceptable. I also went from 2.73 to 3.73 and I also have the same 245/45R17 tires. The stock speedo gear on automatics has 18 teeth.
 

S/CBlack95GT

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Apr 6, 2003
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Tampa Palms, FL
Aug 1, 2007
#4
  • Aug 1, 2007
  • #4
To do it right you need to replace both the drive and driven gear. The speedo will be dead on then. I have the part numbers if you need them.
 
F

Fopar

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Apr 1, 2007
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San Marcos, CA
Aug 1, 2007
#5
  • Aug 1, 2007
  • #5
yes i'm aware of the drive gear issue but 6% will be close enough for now, when the trans needs a rebuild i'll swap it for the 7 tooth.

I found out today ford only makes up to a 21 tooth... sooo anyone know where I can get a 23 tooth in San Diego by friday?
 

The Green GT

No 13 year olds are safe around me.
10 Year Member
Jan 8, 2006
1,269
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99
Louisiana
Aug 1, 2007
#6
  • Aug 1, 2007
  • #6
Fopar said:
yes i'm aware of the drive gear issue but 6% will be close enough for now, when the trans needs a rebuild i'll swap it for the 7 tooth.

I found out today ford only makes up to a 21 tooth... sooo anyone know where I can get a 23 tooth in San Diego by friday?
Click to expand...

Try www.50resto.com and see if you get get rush shipping.
 
D

drewzx3

Active Member
Feb 7, 2004
411
1
28
Louisiana
Aug 1, 2007
#7
  • Aug 1, 2007
  • #7
When you go from 2.73's to 3.73's how bad is the speedometer off? Mine is already off by about 10mph from when I swapped in my white face gauges.
 

The Green GT

No 13 year olds are safe around me.
10 Year Member
Jan 8, 2006
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Louisiana
Aug 1, 2007
#8
  • Aug 1, 2007
  • #8
drewzx3 said:
When you go from 2.73's to 3.73's how bad is the speedometer off? Mine is already off by about 10mph from when I swapped in my white face gauges.
Click to expand...

did you get the right gauges? Cause they should not be off after that.
 
D

drewzx3

Active Member
Feb 7, 2004
411
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Louisiana
Aug 1, 2007
#9
  • Aug 1, 2007
  • #9
The Green GT said:
did you get the right gauges? Cause they should not be off after that.
Click to expand...

Well they were the ones where you had to pull the needles off and the speedo was the only one I screwed up. Dunno why its off but according to them radars setup on side of the road when I'm doing 50 I am really doing 60.
 
F

Fopar

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San Marcos, CA
Aug 1, 2007
#10
  • Aug 1, 2007
  • #10
I need more sources ppls
 

toyman

10 Year Member
Jul 19, 2007
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Vernon BC
Aug 1, 2007
#11
  • Aug 1, 2007
  • #11
In the back of my mind I seem to recall there was a 23 tooth speedo gear available from Jeep/Chrysler that should work. Then again I'm an old fart and my memory isn't as good as it used to be. Probably worth the cost of the call though.
 
F

Fopar

Member
Apr 1, 2007
178
0
16
San Marcos, CA
Aug 2, 2007
#12
  • Aug 2, 2007
  • #12
ok here's another important question, whats the difference between automatic speedo gears and 5 spd?
 
B

bmac50

New Member
Oct 18, 2006
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0
Florida
Aug 2, 2007
#13
  • Aug 2, 2007
  • #13
Fopar said:
Hey guys just finished a gear swap from 2.73s to 3.73s, obviously the speedo is way off. Does anyone know what speedometer gear (VSS gear) count i'll need for the new combo? Tires are 245/45 R17s. I need to do this today and the ford dealership closes at 5 (less than 2 hours).
Click to expand...

http://www.hardcore50.com/technical_articles/Rears_and_Gears.htm
 
I

igotyofire

Member
Feb 26, 2004
774
1
19
Southern California
Aug 3, 2007
#14
  • Aug 3, 2007
  • #14
toyman said:
In the back of my mind I seem to recall there was a 23 tooth speedo gear available from Jeep/Chrysler that should work. Then again I'm an old fart and my memory isn't as good as it used to be. Probably worth the cost of the call though.
Click to expand...

yes if i recall the 50resto site tells you which gear you need. strangly tho for my cobra the speedo gear was already white...looked a lil old and yellowish thats all. but i also heard that that jeep/chrysler gear doesn't mesh well and eventually gets chewed up
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
2
58
Tucson, AZ
Aug 4, 2007
#15
  • Aug 4, 2007
  • #15
Go to a Chrysler dealership. They will have it in stock; the white 23 tooth "mini" gear. It's not cheap ($25 I think) but it will do the job. Mine has lasted 20k miles so far just fine.
Scott
 
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