Transmision question

StormDragon · Sep 18, 2011

Ok Im pretty new to the whole truck scene and epecially 4x4 so Im probably gonna be posting some newbish questions. Ive got an 81F250 2wd that Im going to be putting on an 85 250 4x4 frame. All I got was the frame and axles thats pretty much it. The 2wd has a 300 wih a C6. Id like to use the C6 in the 4x4 frame. My question is can a 2wd trans be adapted for 4wd? Is it as easy as changing the bellhousing to accept a trasfer case or should I just find a 4x4 trans? :hammer:

DNFXDLI · Sep 18, 2011

As far as I know the C6 when in a 4x4 application has a longer output shaft and a housing that joins the transmission to the transfer case...I'm basing that on a 1979 model...more knowing people will be chiming in I'm sure.

StormDragon · Sep 18, 2011

Hmmm

I figured it would be a little more in depth than just a mere bell housing change. All info I can get would be awesome. I could use the trans in another setup if thats the case

Fellro · Sep 19, 2011

Now, please don't take offense, but I want to clear up your terminology to keep from confusing people. Bell housing refers to the end that bolts to the motor, while tailshaft housing refers to the end that goes to the transfer case or driveshaft.

On which is the method, not sure, but from the adventures of Buzzgun, this may well be the way it is. Typically, that is what the changes are, different tail shaft for each configuration, no other real changes.

StormDragon · Sep 19, 2011

Ooops

Yup meant tail shaft lol/ Anyways is that all that needs changed then?

DNFXDLI · Sep 19, 2011

I believe so..and you will also need the intermediate housing that joins the transmission to the transfer case, assuming that those years are setup the same way as the 79's.

BuzzGun79 · Sep 19, 2011

YEP i just went through this with my 79 F250 C-6 you will need to change the output shaft,part # 036678D it measures 18 1/2" in lenghth.also you will need a tail stock so it will bolt up to the transfer case.{i already had this} then it will work.

BuzzGun79 · Sep 19, 2011

I also recommend you double check my part # to your application before you jump into it. Ford used several different size output shafts in the C-6 {i found this out the hard way..lol} same for the tail stock as i believe some of the transfer cases are different from the 79 model.

BuzzGun79 · Sep 19, 2011

just so you know to change the output shaft in the C-6 requires a complete tear down of the transmission. i would hate to see you go through what i did. im glad i had someone else build the trans because the mistake fell back on them.initially they installed the wrong out put shaft.its a long story...Bob

StormDragon · Sep 19, 2011

Ick

Sounds like I just need to find a 4x4 setup then. I found a 351M for $100 running and have seen several 78 and 79 trans and transfer cases around. Those should bolt no issues or minor fabrication on my 85 frame then?

Fellro · Sep 19, 2011

85 didn't come with any M configurations, so minor mods may be needed. the 400 motors stopped in 82. Most likely, you only need to transfer the motor mount towers.

StormDragon · Sep 19, 2011

Well....

I do have my 300 I6 yet in the 81 body. But am curious if the transfer case drive shaft will line up with the 85s axle or should be looking at newer and not older for the drive line?

Fellro · Sep 19, 2011

Lineup should be the same. The offset didn't change.As long as it is all 80 and newer, it trades mostly. I can't say absolute if the 79 and older will swap in.

StormDragon · Sep 19, 2011

hmmm

on older than 80 is the pumpkin for the front axle on the drivers or passnger side? on my 85 axle its on the drivers side. :headbang:

Fellro · Sep 19, 2011

Yep, for a long time Ford was the only one on that side, then GM switched, as did Dodge.

StormDragon · Sep 19, 2011

so..

so i definitly need to find a drive line newer than 79. did they make this change in 80 or was it closer to 85?

Fellro · Sep 20, 2011

No, you misunderstood. Ford has the driveshaft on the driver side from way back, not even sue when they started doing it, maybe from the beginning, I don't know, but well into the 60's. The divorced case is more trouble than you need for a general driver, so you would want to stick with married, but I can't say how trouble free they would be to mount in.

StormDragon · Sep 20, 2011

Research

I guess I need to research things further. The trans and transfer case Im looking at came out of a 79 250. I wasnt sure if those were gonna work with my front axle. Like I said Im a rookie when it comes to this. Ive restored Mustangs for the past 18 years lol. Whats the difference between divorced an married transfer cases?

Fellro · Sep 20, 2011

Divorced cases have a little drive shaft between them and the transmission, while married are directly attached to the transmission though an adapter housing. A 79 should be a married case, as the divorced cases were discontinued at the 77.5 production year.

BuzzGun79 · Sep 20, 2011

just an fyi.there is a transfer case mounting perch on the drivers side frame rail of my 79 F-250 that also holds my married case.if you look in my gallery of pics i posted a couple of pics so you can see my setup.

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Transmision question

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