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Learned Something New Today...

  • Thread starter Thread starter ID89GT
  • Start date Start date Jun 25, 2012

ID89GT

10 Year Member
May 26, 2008
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49
Spokane Valley, WA
Jun 25, 2012
#1
  • Jun 25, 2012
  • #1
That not all 4 eye gauge clusters are the same lol. I went to swap the cluster from my 85 to my 80 because I wanted the 140 speedo in the 85.. Well once I plugged it in, the brake light and the right turn signal bulb were on and the key wasn't even in. Then I started smelling a burning smell and sure enough the back of the gauge cluster is smoking -.- Well lesson learned not all 4 eye gauge clusters are interchangeable. So here comes to where I need help, what years ARE interchangeable since I need a new cluster for my 85 Mustang now lol. I also figured out all I had to do was pull the lense off and 2 bolts on the back and bam, speedo comes out..

I also have another question that kinda ties in with the first question.. Now that the 80 Mustang has an 85 speedo instead of the 140, what speedometer gear do I need to make the speedo read correctly again? It does have 373 gears, and is a t5 trans. Thanks
 

jrichker

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#2
  • Jun 28, 2012
  • #2
What year T5 transmission and what tire size to you have?

See http://www.fordracingparts.com/download/charts/129.pdf for a chart by Ford Racing Performance Parts

Or see http://www.latemodelrestoration.com/page/Mustang-Speedometer-Gear-Application-Guide

Or see below...



Or see http://www.latemodelrestoration.com/page/Mustang-Speedometer-Gear-Application-Guide
 

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ID89GT

10 Year Member
May 26, 2008
1,659
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Spokane Valley, WA
Jun 28, 2012
#3
  • Jun 28, 2012
  • #3
Not sure on the year t5, its out of an aero nose Mustang is all I know :/ As for tire size it has 225/50r16 on it now with the svo wheels
 
N

NXcoupe

Active Member
Dec 3, 2009
80
27
28
Dayton, OH
Jun 29, 2012
#4
  • Jun 29, 2012
  • #4
ID89GT said:
That not all 4 eye gauge clusters are the same lol. I went to swap the cluster from my 85 to my 80 because I wanted the 140 speedo in the 85.. Well once I plugged it in, the brake light and the right turn signal bulb were on and the key wasn't even in. Then I started smelling a burning smell and sure enough the back of the gauge cluster is smoking -.- Well lesson learned not all 4 eye gauge clusters are interchangeable. So here comes to where I need help, what years ARE interchangeable since I need a new cluster for my 85 Mustang now lol. I also figured out all I had to do was pull the lense off and 2 bolts on the back and bam, speedo comes out..

I also have another question that kinda ties in with the first question.. Now that the 80 Mustang has an 85 speedo instead of the 140, what speedometer gear do I need to make the speedo read correctly again? It does have 373 gears, and is a t5 trans. Thanks
Click to expand...
Nothing, swapping the speedo will not be affected by what speedo gear you have, speedos are cal'd to display speed according to a std cable rpm that ford uses from year to year. I swapped a 140 into my 88 replacing the 85 mph gauge and it worked just as the 85 did. Going the other way will have similar results. So if your speedo was accurate with the 140, it will also be accurate with the 85.
 

ID89GT

10 Year Member
May 26, 2008
1,659
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Spokane Valley, WA
Jun 29, 2012
#5
  • Jun 29, 2012
  • #5
Haha sweet, good to know
 

rd

Founding Member
Jan 12, 2000
3,316
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109
Ocean Springs MS
Jul 3, 2012
#6
  • Jul 3, 2012
  • #6
Been there done that! Swapped the 80 cluster into the 82 and fried the ammeter wiring. So----figured the pinouts on both and compared. Very different.

Reinstalled the 82 cluster and all was well. The dash harness is set to match the cluster. Both the 82 and 80 under hood harness seem to work, iirc. I still have the 80 engine bay harness in the car. It appears the under hood stuff pins in the same way, and the dash harness does the translation.

I think the 79s are also different than any that came later.
 

ID89GT

10 Year Member
May 26, 2008
1,659
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49
Spokane Valley, WA
Jul 3, 2012
#7
  • Jul 3, 2012
  • #7
Hmm ill probably just look for another 85 one then so I don't mess anything up lol
 
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