Change over from automatic to manual

[Cole Hamley]

I have a 79 bronco had a 400 c6 automatic trans. Im changing to 390 4 speed and the marriage conection from my transfer cace to the new 4 speed dont line up it has 6 holes instead of 4 like I need. what do I do im 17 years old and this is my first big project on my dream truck. some body please help me?

 

[davids78bronco]

Why are you doing this? THe 400 is a perfectly good engine. While the 390 is badass in itself, there's quite a bit of work involved, to fit an FE engine in a truck that wasn't built to hold one.

Worst case senario, find a Tcase adapter. It really should be that easy. Just make sure it's the same length, as there are two different lengths offered for the Bronco

 

[Cole Hamley]

I have a 79 bronco had a 400 c6 automatic trans. Im changing to 390 4 speed and the marriage conection from my transfer cace to the new 4 speed dont line up it has 6 holes instead of 4 like I need. what do I do im 17 years old and this is my first big project on my dream truck.  some body please help me?

32567[/snapback]

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yes it is a good motor but I like the 390 and I hate the automatic. can I just get a trans and tcase out of a old 4speed bronco and put in mine?

 

[jgvabronco]

You're on the right track getting an already married 4-spd and t-case. Keep the bell to the FE, and that should line up to the front of the trans. If you have a good case already, all you really need is an NP-435 or T-18 out of any 70's 1/2 ton Ford 4X4, or any 3/4 ton or 1 ton Ford 4X4 from 77-79. But now I gotta say it too. You are in for a ton of mods to put an FE in the Bronc for no gain. Stay with the 400. Btw, you may just need the t-case adapter since it doesn't sound like you have the tailshaft housing on there. If the spline count on the output has 31-splines, and is around 10" long, that is probably all you need. But it must be a 4WD 4-spd, not a 2WD 4-spd or the tailshaft will not be right.