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Ford Bronco Parts - Classic Vintage Early Bronco Parts

C4 3 speed automatic – Transmission Guide

Tech article by admin and filed under - Automatic, Transmission

Tech article by Jon Hanna (Admin)

Automatic Trans Intro
Gear Ratio Chart
AODE & 4R70W
See also Manual Trans
C4 Transmission

C4 3 speed automatic
1973-1977 Broncos as well as several other Ford cars and trucks from 1964-1981
Unlike the other transmissions in this article, the C4 has a removable bell housing. Also see the transmission pan image above for identification.
Adapter required?
Because the C4 was a stock option on Broncos an aftermarket adapter isn’t needed if you can find a stock unit. If not there are aftermarket adapters available.
This is the simplest, most straightforward and least expensive automatic transmission option because it was originally available on 1973-1977 Broncos. Find a donor Bronco with a C4 and transfer parts. Although the C4 was originally designed for smaller V8’s it has a strong aftermarket following and can take a lot of abuse if built properly.
The C4 has a fairly high first gear without the modern advantages of overdrive. In completely stock form the C4 can be a little weak for high output engines.
Cost: (Approximate)
Transmission: $150-500 used and $500-1400 rebuilt (expect to pay near the upper end of this range if you are getting your C4 out of a 73-77 Bronco.
Adapter kit: $500-550
Drive Shaft Mods:
Total transmission is approximately 1.5″ longer requiring some drive shaft modifications.
Bell housing:
The C4 came behind small block Ford engines and will bolt up to your 289-302-351 engine.
Modifications needed:
Very few modifications are needed if using a C4 out of a Bronco.

Manual Transmissions 1st 2nd 3rd 4th 5th
Bronco 3 spd (6 cyl) 3.41 1.86 1.00
Bronco 3 spd (8 cyl) 2.99 1.75 1.00
NP 435 6.69 3.34 1.79 1.00
T-18 6.32 3.09 1.69 1.00
Toploader (Close ratio) 2.32 1.69 1.29 1.00
Toploader (Wide ratio) 2.78 1.93 1.35 1.00
Toploader (Overdrive) 3.29 1.84 1.00 0.81
ZF 5.72 2.94 1.61 1.00 0.76
NV4500 (Dodge) 5.61 3.04 1.67 1.00 0.73
Automatic Transmissions 1st 2nd 3rd 4th 5th
Bronco C4 2.46 1.46 1.00
C6 2.46 1.46 1.00
AOD 2.40 1.47 1.00 .67
AOD w/ low gear set 2.84 1.55 1.00 .67
AODE/4R70W* 2.84 1.55 1.00 .67
700R4 3.06 1.62 1.00 .70

2 Responses to “C4 3 speed automatic – Transmission Guide”

  1. TRANSMISSION SWAP - Ford Truck Enthusiasts Forums Says:

    […] the CB tech article on all the trannys that will work with the EB… C4 3 speed automatic – Transmission Guide | Tech Articles To add to Chad's list if you went with a C4, you'd need an auto steering column and tranny cooler. […]

  2. broncal Says:

    will my transfer case from my 68 strait stick with the T shifter bolt up to the 73 c4 automatic unit from a bronco, and how do you mate them and keep the balls in place?

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