drive shaft help needed

helpingmybro · Nov 20, 2010

Hey guys.

First off, this is a great site! My brother bought a '75 a while back and we've been making some mods, learning as we go. Neither of us know anything about working on cars/trucks, but we're trying.

Our latest issue: we put on the rear suspension last week and it went pretty well. However, when we jacked up the rear and placed the frame on stands, the rear drive shaft slipped apart at the splines (am I saying that right?) when we lowered the jack from the pumpkin.

We didn't expect it so we didn't mark it. How do I connect the lower half to the upper? In searching this site I read that folks should mark it before separating them, but obviously we didn't.

Thanks for your time.

70_Steve · Nov 20, 2010

helpingmybro said:
We didn't expect it so we didn't mark it. How do I connect the lower half to the upper? In searching this site I read that folks should mark it before separating them, but obviously we didn't.

Most important thing when putting the drivshaft together is proper phasing. Sounds compicated but it's not really. The pic below should explain it.

garberz · Nov 20, 2010

You need a longer drive shaft. Now with a suspension lift, the rear end is farther away from the transfer case, making the drive shaft too short. Even if just driving on the street, you risk the suspension cycling and the drive shaft coming apart. That wouldn't be pretty.

helpingmybro · Nov 20, 2010

Thanks for the info so far.

The shaft halves came apart when we were removing the original suspension. We will see if they slip back apart now that the new 3.5" is on, but first I need find out how to put them back together.

Thanks again.

Steve83 · Nov 22, 2010

.

helpingmybro · Nov 23, 2010

Thanks again.

One more silly question: in order to slip the two halves back together, do I need to remove the part of the lower shaft that has the grease fitting? If so, how does it come off -- unscrew, slide, etc? (I hope these questions make sense.)

Sorry for the silly Q's.....

Steve83 · Nov 23, 2010

If it came out, it should go back. Just grease it up and...

kancox · Nov 23, 2010

70_steve gave a good simple explanation of drive shaft configuration and as garberz said your driveshaft may now be to short,but i would look at pinion angle next. Search pinion angle in the bronco tech on this site,it walks you through the simple process.On my 72,dana 20,3 speed I replaced a outdated 3 1/2 lift(po already installed a longer rear driveshaft)my pinion angle was 14 degrees.I rotated the spring perches 9 degrees and ended up at 1.5 degrees,i'm happy,but the point is i gained probably 1inch of driveshaft travel back

drive shaft help needed

helpingmybro

New Member

70_Steve

Old Guy

Attachments

garberz

Bronco Influencer

helpingmybro

New Member

Steve83

Bronco Guru

helpingmybro

New Member

Steve83

Bronco Guru

kancox

Full Member

Similar threads