• Mustang Forums
  • 1974 - 1978 Mustang II Talk & Tech

V6 Transmission Swap

  • Thread starter Thread starter 22hp
  • Start date Start date Nov 20, 2011
2

22hp

New Member
Nov 6, 2011
4
0
1
Nov 20, 2011
#1
  • Nov 20, 2011
  • #1
Looking to convert a 78 Mustang II with a 2.8 V6/ 4 speed to a C4 automatic. Has anyone out there done this swap?
I would like to confirm what parts are needed.
I’m thinking I’ll need; flywheel, torque converter, bell housing, transmission with floor shift linkage, shifter and driveshaft.
From what I understand the flywheel, torque converter and bell housing can also be sourced from V6 Rangers and Bronco IIs up to 84.
Anything I’m missing or any other “gotchas”?
 

LILCBRA

I wish I didn't have all of these balls in the air
Mod Dude
Dec 6, 2005
6,347
5,322
194
Corn County USA
Nov 21, 2011
#2
  • Nov 21, 2011
  • #2
Tranny cooler unless your radiator has provisions and cooling lines. Also, and someone else can speak up if I am wrong, might need to have a different length driveshaft. I know V8 cars are about 1" different...
 

Mstng2

Founding Member
Jun 27, 2002
789
5
19
- - Zion - -
Nov 21, 2011
#3
  • Nov 21, 2011
  • #3
I swapped mine out, you do need an automatic driveline, and a Transcooler as mentioned above. The shifter hole is an exact fit, and for the clutch pedal you simply remove the rod above the pedal remove the pedal and put it back. then just use the same brake pedal, it's smaller than an auto pedal but it's fine. The trans cross member can be re-used for the C4 but you'll need the trans mount (The rubber piece that goes between the crossmember and the transmission.) You'll need a speedo cable specific for the Auto, and also a nuetral saftey switch. (easier to just bypass this but up to you)

Enjoy!
 
2

22hp

New Member
Nov 6, 2011
4
0
1
Nov 21, 2011
#4
  • Nov 21, 2011
  • #4
Thanks guys, great information, just what I was looking for!
Will the 302 automatic driveshaft work as well or do I specifically need a v6 automatic driveshaft?
 

78CobraII

Moderator
Jul 31, 1998
1,808
8
39
Birmingham, AL
Dec 19, 2011
#5
  • Dec 19, 2011
  • #5
I think that your V6 4-speed driveshaft has a good chance of being 1 inch too long, but its not too big of a deal to get it shortened. The 302 AT driveshaft is probably the correct length.

Personnly I'd be tempted to use an overdrive trans out of a later Ranger or Explorer with a V6. They aren't exactly known for their durability, but if you are putting it behind a factory 2.8L,it should hold up fine. And there are hipo parts out there for this trans. While you are doing the OD trans though, why not grab the 4.0L OHV engine that goes with it and get both EFI and OD for more performance and mileage?

Don't the early Ranger and Bronco II actually use the C5? The difference is mostly in the lock up torque converter, but there are some wiring differences between the trans too.
 

Blue coyote

Founding Member
Sep 14, 2002
347
0
16
North America's hemp-basket, BC, Canada
Dec 20, 2011
#6
  • Dec 20, 2011
  • #6
The parts from the Ranger/Bronco II/Explorer will work, as long as the donor is a 2wd with the 2wd tailhousing (the 2wd BII uses a "dummy" transfer case) and as long as you use the matching starter for the flexplate.

Using a C5 out of an early 2wd Ranger is probably the best option, with a lockup torque converter (sort of) acting as an O/D without the reliability issues associated with the A4LD. Personally, I wouldn't even trust an A4LD spec'ed out for a built 4.0. They are based off the marginally self-destructive C3, but with an overdrive AND a lockup converter both adding strain to a POS tranny.
 
You must log in or register to reply here.

Similar threads

Mustang II V6 conversion to V8 HO and T5 problems and solutions
  • greenflash79
  • Jul 6, 2025
  • 1974 - 1978 Mustang II Talk & Tech
  • 2
Replies
34
Views
2K
1974 - 1978 Mustang II Talk & Tech Jan 29, 2026
greenflash79
K
3.8 T5 & Bellhousing to 1987 Lincoln 5.0
  • ks65stang
  • Mar 2, 2026
  • Other Auto Tech
Replies
3
Views
288
Other Auto Tech Mar 3, 2026
Noobz347
C
SN95 Another Coyote swap list
  • catkiller
  • May 10, 2026
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
0
Views
106
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- May 10, 2026
catkiller
C
F
C4 Transmission
  • Fri Guy
  • Jan 23, 2025
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
3
Views
811
1965 - 1973 Classic Mustangs -General/Talk- Jan 23, 2025
LILCBRA
C
5r55s auto to TR3650 Manual swap 4.0 V6
  • Ceskz
  • Feb 24, 2025
  • 2005 - 2014 Specific V6 Tech
Replies
7
Views
1K
2005 - 2014 Specific V6 Tech Mar 27, 2025
89ripper
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1974 - 1978 Mustang II Talk & Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?