Cliff: /* Final-drive relationship */

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Final-drive relationship

@@ Line 146: / Line 146: @@
 {| class="wikitable"
-! Code
+! Transmission code
 ! Transmission
 ! Commonly listed final drive
@@ Line 169: / Line 169: @@
 | Muncie/Getrag 5-speed
 | 3.61
 |}

Cliff: /* Final-drive relationship */

2026-07-22T12:59:42Z

Final-drive relationship

← Older revision		Revision as of 12:59, 22 July 2026
Line 149:		Line 149:
	! Transmission		! Transmission
	! Commonly listed final drive		! Commonly listed final drive
	~~! Notes~~
	\|-
	~~\| F17~~
	~~\| 2.84 final-drive ratio~~
	~~\| Transmission / final drive~~
	~~\| Listed in enthusiast/forum references; verify application~~
	\|-
	~~\| F75~~
	~~\| 3.18 final-drive ratio~~
	~~\| Transmission / final drive~~
	~~\| Listed in enthusiast/forum references; verify application~~
	\|-
	~~\| FW2~~
	~~\| 3.06 final-drive ratio~~
	~~\| Transmission / final drive~~
	~~\| Listed in forum reference as 1985-1986 V6 automatic application~~
	\|-
	~~\| FX4~~
	~~\| 3.35 final-drive ratio~~
	~~\| Transmission / final drive~~
	~~\| Listed in enthusiast/forum references; verify application~~
	\|-		\|-
	\| MY8		\| MY8
	\| Muncie 4-speed		\| Muncie 4-speed
	\| 3.32		\| 3.32
	\|
	\|-		\|-
	\| M19		\| M19
	\| Muncie 4-speed		\| Muncie 4-speed
	\| 4.10		\| 4.10
	\|
	\|-		\|-
	\| M17		\| M17
	\| Muncie 4-speed		\| Muncie 4-speed
	\| 3.65		\| 3.65
	\|
	\|-		\|-
	\| MT2		\| MT2
	\| Isuzu 5-speed		\| Isuzu 5-speed
	\| 3.35		\| 3.35
	\|
	\|-		\|-
	\| MG2		\| MG2
	\| Muncie/Getrag 5-speed		\| Muncie/Getrag 5-speed
	\| 3.61		\| 3.61
	\|
	\|}		\|}

Cliff: /* Final-drive relationship */

2026-07-22T12:58:56Z

Final-drive relationship

← Older revision		Revision as of 12:58, 22 July 2026
Line 174:		Line 174:
	\| Muncie 4-speed		\| Muncie 4-speed
	\| 3.32		\| 3.32
			\|
	\|-		\|-
	\| M19		\| M19
	\| Muncie 4-speed		\| Muncie 4-speed
	\| 4.10		\| 4.10
			\|
	\|-		\|-
	\| M17		\| M17
	\| Muncie 4-speed		\| Muncie 4-speed
	\| 3.65		\| 3.65
			\|
	\|-		\|-
	\| MT2		\| MT2
	\| Isuzu 5-speed		\| Isuzu 5-speed
	\| 3.35		\| 3.35
			\|
	\|-		\|-
	\| MG2		\| MG2
	\| Muncie/Getrag 5-speed		\| Muncie/Getrag 5-speed
	\| 3.61		\| 3.61
			\|
	\|}		\|}

Cliff: /* Final-drive relationship */

2026-07-22T12:58:32Z

Final-drive relationship

← Older revision		Revision as of 12:58, 22 July 2026
Line 149:		Line 149:
	! Transmission		! Transmission
	! Commonly listed final drive		! Commonly listed final drive
			! Notes
	\|-		\|-
	\| F17		\| F17

Cliff: /* Final-drive relationship */

2026-07-22T12:57:58Z

Final-drive relationship

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 ! Transmission
 ! Commonly listed final drive
 |-
 | MY8

Cliff: Created page with "'''Transmission RPO codes''' are RPO codes used to identify factory transmission equipment on the Pontiac Fiero. For a complete searchable list of Fiero RPO and option codes, see: * Fiero RPO code list == Overview == The Pontiac Fiero was available with several factory manual and automatic transaxles. Transmission RPO codes help identify which transmission a car was originally equipped with from the factory. These codes may appear on the Service parts..."

2026-07-22T12:24:58Z

Created page with "'''Transmission RPO codes''' are RPO codes used to identify factory transmission equipment on the Pontiac Fiero. For a complete searchable list of Fiero RPO and option codes, see: * Fiero RPO code list == Overview == The Pontiac Fiero was available with several factory manual and automatic transaxles. Transmission RPO codes help identify which transmission a car was originally equipped with from the factory. These codes may appear on the Service parts..."

New page

'''Transmission RPO codes''' are [[RPO codes]] used to identify factory transmission equipment on the [[Pontiac Fiero]].

For a complete searchable list of Fiero RPO and option codes, see:

* [[Fiero RPO code list]]

== Overview ==

The Pontiac Fiero was available with several factory manual and automatic transaxles.

Transmission RPO codes help identify which transmission a car was originally equipped with from the factory. These codes may appear on the [[Service parts identification label]] along with engine, paint, trim, wheel, audio, and other factory build codes.

The RPO code identifies original factory equipment. It does not necessarily prove what transmission is currently installed, because many Fieros have been repaired, rebuilt, transmission-swapped, engine-swapped, or modified.

Related topics:

* [[Transmission]]
* [[Transmission identification]]
* [[Transmission gear ratios]]
* [[Service parts identification label]]

== Factory transmission RPO codes ==

{| class="wikitable sortable"
! Code
! Transmission
! Type
! Common Fiero usage
! Notes
|-
| MD9
| [[TH125 automatic|125C / TH125C automatic transaxle]]
| 3-speed automatic
| Automatic-equipped Fieros
| Factory automatic transaxle used throughout Fiero production
|-
| MY8
| [[Muncie 4-speed]]
| 4-speed manual
| Economy-oriented 1984 four-cylinder application
| 3.32 final-drive ratio
|-
| M19
| [[Muncie 4-speed]]
| 4-speed manual
| 1984 four-cylinder performance application
| 4.10 final-drive ratio
|-
| M17
| [[Muncie 4-speed]]
| 4-speed manual
| V6 four-speed application
| 3.65 final-drive ratio
|-
| MT2
| [[Isuzu 5-speed]]
| 5-speed manual
| Four-cylinder five-speed application
| 3.35 final-drive ratio
|-
| MG2
| [[Getrag 5-speed|Muncie/Getrag 5-speed]]
| 5-speed manual
| V6 five-speed application
| 3.61 final-drive ratio
|}

== MD9 ==

'''MD9''' identifies the 125C / TH125C three-speed automatic transaxle used in automatic-equipped Fieros.

The TH125 automatic was available with both the [[Iron Duke|2.5L four-cylinder]] and [[2.8L V6]] engines.

Related topics:

* [[TH125 automatic]]
* [[Automatic transmission]]
* [[Transmission fluid]]
* [[Torque converter clutch]]

== MY8 ==

'''MY8''' identifies a Muncie four-speed manual transaxle used in 1984 four-cylinder Fieros.

It is commonly associated with the 3.32 final-drive ratio and is often discussed as the economy-oriented 1984 four-speed.

Related topics:

* [[Muncie 4-speed]]
* [[Transmission gear ratios]]
* [[Manual transmission]]

== M19 ==

'''M19''' identifies a Muncie four-speed manual transaxle used in 1984 four-cylinder Fieros.

It is commonly associated with the 4.10 final-drive ratio and is often discussed as the shorter-geared 1984 four-speed.

Related topics:

* [[Muncie 4-speed]]
* [[Transmission gear ratios]]
* [[Manual transmission]]

== M17 ==

'''M17''' identifies the Muncie four-speed manual transaxle used with V6 Fieros before the later V6 five-speed became available.

It is commonly associated with the 3.65 final-drive ratio.

Related topics:

* [[Muncie 4-speed]]
* [[2.8L V6]]
* [[Manual transmission]]

== MT2 ==

'''MT2''' identifies the Isuzu five-speed manual transaxle used with four-cylinder Fieros.

In Fiero owner usage, this transmission is commonly called the [[Isuzu 5-speed]].

Related topics:

* [[Isuzu 5-speed]]
* [[Iron Duke]]
* [[Manual transmission]]
* [[Transmission fluid]]

== MG2 ==

'''MG2''' identifies the five-speed manual transaxle used with V6 Fieros.

In Fiero owner usage, this transmission is commonly called the [[Getrag 5-speed]]. Factory service information may identify the same transmission as the Muncie 282 five-speed manual transaxle.

Related topics:

* [[Getrag 5-speed]]
* [[2.8L V6]]
* [[Manual transmission]]
* [[Transmission fluid]]

== Final-drive relationship ==

Some Fiero transmission RPO codes are closely associated with final-drive ratios.

{| class="wikitable"
! Code
! Transmission
! Commonly listed final drive
|-
| MY8
| Muncie 4-speed
| 3.32
|-
| M19
| Muncie 4-speed
| 4.10
|-
| M17
| Muncie 4-speed
| 3.65
|-
| MT2
| Isuzu 5-speed
| 3.35
|-
| MG2
| Muncie/Getrag 5-speed
| 3.61
|}

For the automatic transmission, final-drive ratio can vary by year and transmission code. See:

* [[Transmission gear ratios]]
* [[Transmission identification]]
* [[TH125 automatic]]

== RPO code versus installed transmission ==

The transmission RPO code identifies the transmission originally assigned to the car when it was built.

It does not prove that the same transmission is still installed.

Many Fieros have had transmission replacements, clutch repairs, engine swaps, manual-to-automatic conversions, automatic-to-manual conversions, or drivetrain swaps.

When ordering parts or diagnosing a transmission, use the RPO code together with physical inspection of the actual installed transmission.

== Transmission identification ==

Transmission identification should include:

* [[Service parts identification label]] RPO code
* Transmission case features
* Shift-cable arrangement
* Clutch or automatic-shifter hardware
* Dipstick or fill/check arrangement
* Axle and mount arrangement
* Transmission tag, stamping, or code, where present
* Model year and engine combination
* Previous repair or swap history

Because Fiero transmissions are interchangeable in some situations, physical identification is important.

Related topic:

* [[Transmission identification]]

== Relationship to engine RPO codes ==

Transmission RPO codes are often interpreted together with engine RPO codes.

The main Fiero engine RPO codes are:

{| class="wikitable"
! Code
! Engine
! Common name
|-
| LR8
| 2.5L four-cylinder
| [[Iron Duke]]
|-
| L44
| 2.8L V6
| [[2.8L V6]]
|}

A car's original engine and transmission combination can be checked using the Service Parts Identification label, but the current installed drivetrain should still be inspected directly.

Related topic:

* [[Engine RPO codes]]

== Common mistakes ==

Common mistakes when using transmission RPO codes include:

* Assuming the RPO label proves the current transmission is original
* Confusing [[Isuzu 5-speed]] and [[Getrag 5-speed]] units
* Assuming all five-speed Fieros used the same transmission
* Assuming every V6 car has a Getrag 5-speed
* Assuming every four-cylinder five-speed is suitable for a V6 application
* Confusing transmission RPO codes with gear-ratio codes or transmission case codes
* Ordering parts based only on model year instead of identifying the installed transmission

== Service notes ==

When using transmission RPO codes:

* Check the [[Service parts identification label]] first.
* Verify the installed transmission physically before ordering parts.
* Check year, engine, transmission type, and RPO code together.
* Use [[Transmission identification]] when the car has unknown history.
* Use [[Transmission gear ratios]] when exact gearing matters.
* Be cautious with swapped or rebuilt cars.
* Do not assume the current transmission matches the original RPO label.

== Notes ==

Transmission RPO codes are factory build references. They are useful for identifying how a Fiero was originally equipped, but they are not a complete history of the car.

For modified, repaired, or swapped cars, direct inspection of the installed transmission is more important than the original RPO code alone.

== See also ==

* [[RPO codes]]
* [[Fiero RPO code list]]
* [[Service parts identification label]]
* [[Transmission]]
* [[Transmission identification]]
* [[Transmission gear ratios]]
* [[Transmission fluid]]
* [[TH125 automatic]]
* [[Muncie 4-speed]]
* [[Isuzu 5-speed]]
* [[Getrag 5-speed]]
* [[Engine RPO codes]]
* [[Engine swaps]]

[[Category:Fieropedia]]
[[Category:Reference]]
[[Category:RPO codes]]
[[Category:Transmission]]

Transmission RPO codes - Revision history

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Cliff: /* Final-drive relationship */

Cliff: /* Final-drive relationship */

Cliff: /* Final-drive relationship */

Cliff: /* Final-drive relationship */