The how to guide for shortening a driveshaft

This is for the front shaft which is part time and I don't care about balancing it.

First off-  I measured the fully collapsed length then measured the fully extended

length, subtracted and divided by 3.  Why 3?  Why not.  I figured that with 1/3 of the

slip shaft hanging out at regular running setting that it would be strong enough.

The 1/3 is 1.5" from the weld nipple.  Thank goodness for nipples.

Stock length with the 1.5" extension was 39" center to center on u joints.

Which means after measuring the centerline ujoint cap at the differential to the 39" shaft length,

 I needed to take off 2 3/8" to make it the right length.

I thought these were solid due to the weight, but I was mistaken.

The yolk is press fitted and welded on.  The end of the stock tube was originally

 chamfered to make assembly a little easier.

The yolk got cut into some with the angle grinder, so it was filled in and

ground down to a roundish configuration.

I measured like in the pictures down below before seating it to weld.

Do this on a flat surface and check your  measurements twice.

Then weld away......

Quick after weld check...

It's actually even!

 

Paint it and insert ujoints. Then grease the heck out of it.  If you forget to grease it, you'll be replacing the joints again

within a week- trust me.

driveshaft clearances

Rear one has 2.5" of travel and needs to be extended (unless I can get some DOM tubing a professional shop will do this)from full extension 2.5" to reach the transfer case.
The front one will be cut down and rewelded.   I almost stroked out on the front one trying to measure  it.  With the transfer case in and clocked the way I had the shifters mounted, the driveshaft yolk would contact the transmission pan. 
So before I started trying to rotate the transfer case, I put a spare u joint on the shaft and held it in place.  Almost straight out the shaft would rotate without any binding, as soon as the axle end was dropped down it came in contact with the tranny pan lip just outside the bolts. 

  I'll have to pull the tranny pan and shave off the 1/4" lip of the pan (hatched area)  to clear the yolk.

Since it is so close to the pan and aluminum part of the tranny,  it will receive a racing hoop coming off the crossmember that it will pass through to keep it from going thru the pan incase of a ujoint failure. (orange scribbly looking thing)

Update:  The pan is now silver.  And I removed the extra flange. 

The driveshaft is a scant millimeter from hitting when turning.

parking brake

Nothing too exciting here.  The original parking brake bracket which used to bolt to the crossmember was

too short to reach now since the crossmember moved forward.  I welded an extension bracket that moved

 it about 6" back.

 The cables coming out of the backing plates were stretched tight in their original positions just sitting still.
I moved the cable mounts back about 4" so when the rear axle moves they won't bind it up. I tested the brake and it stayed on so I need to get into the rear drums to see whats up with that.  At least they work.

And after doing this, the parking cable was froze in its housing.  :(

Here the exposed cable ( in the above picture) was coated with anti seize

and pulled through with line pliers.  Then the pulled out portion was

anti seized and pulled back thru. 

They loosened up after a couple times

After this, make sure that NO anti seize is left in the brake drum

it will render the brakes nearly useless. (not that they are great right now)

Spray down EVERYTHING with brake cleaner to get off dirt, and grease that may have

gotten in there. If the shoes are greasy or oily, replace them.

TODO LIST: (seems big, just smaller stuff now)
Oil filter housing replacement, transfer shifter handles, rear driveshaft lengthened 3" +/-, front driveshaft shortened 3"+/-,rear brake line, adjust rear parking brake, check front master cylinder and slaves after rear brake line, alternator, plug back in dash / hvac controls and clean up wiring, rear light wiring.

priceless

Camera phone with 2 year contract $4000.

A pic of the transmission shifter from above=  $0.01

The shifter rail for the transfer case= $10.00

Twin stick shifters in the original floorboard hole =Priceless.

I've had several people coming up to me saying they "had a scout or bronco just like mine" when they were younger.

I just look at the Jeep embossed logo on the grill and the Commando logo on the side, smile and shake my head.

Transfer case shifters

The original shifter was on a long tube that came from the dana 20 case. The new shifter will have independant sticks
like below.

before: the new sticks.

After: With everything hooked up and the case able to shift, the sticks, in middle position, are too far forward. They almost lay on the floor pan in full forward position.
  Either the sticks need to be bent back towards the rear or the mount needs to be shortened.

Note the classy shift pattern diagram taped next to it. (below)




I need to stay out of the upper right and lower left boxes to keep from blowing up axles, transfer case, driveshafts, etc....

Update 12-16-11 - got them mounted and angled towards the back so I don't knock knuckles on the cover plate.  They are both straight instead of angled. The left stick shifts easily, the right hi n lo stick takes some coercing, just needs a good breaking in I bet.

Fixing and learning

I finally got off my keester and fixed the transmission crossmember so the rear isn't held up by a jack.

I initially dreaded fixing the crossmember because I'd have to weld a nut into the frame. Where the bolt in the picture is is the front original mounting position and the empty hole needed a nut.

When I got the wire wheel on the angle grinder to it, cleaned 38 years of grease, dirt, and undercoating,

 I found that Jeep was kind enough to put a threaded hole every 4 inches for a foot or so.  I guess this was for

the different configurations of the cj-6 and commando frame.  So it turned out to be a dirty job, but not a hard job.

I drilled a hole just behind the original one to make a slot.

The completed original crossmember cleaned and painted

Also got the 700R4 shifter to AMC adapter finished. The shiny part is newly created.
Now I don't have to crawl under anymore!

This,  THIS was giving me heartburn! I thought that the transmission was going to have to come out. 

I pulled the dana 300 (which I needed to do anyway) because there was a constant drip of tranny fluid coming out and dripping off the dana 300.

I called the guy that rebuilt it, and he said this area under the governor gear (green) is supposed to get some fluid into it to keep it lubed.  I hadn't put on a rear gasket to xfer case so that's why it leaked. whew!

While the transfer case was out I mapped the different shift positions since it doesn't have a shift interlock pill in it.
12&3 are the shaft positions, x= where the left and right shaft is respectively.
As you can see, the upper right and lower left  positions are BAD!
They would run one axle in low range and one in high range at the same time!

Can I get a WOOT!

The intake went on w/new gaskets, distributor only had to be stabbed twice thanks to marking locations on it. 
  The new heater hose fitting had its bottom 3 threads lightly ground down in a tapered fashion, and I cut a notch in the threads to clean out the old fitting before putting it on w some industrial teflon tape.  No cracks this time.  I marked it to be able to be screwed in 4X instead of the 5X that they did on the old one. Unfortunately chebby cant bolt down a completed manifold because of parts in the way. So some stuff went in after torquing down. 
  BTW on the front and rear valley pan
make a rtv gasket on the block and let it set for 20-40 minutes, then put on the manifold w a light smearing of rtv on it.

After sitting 2 days I re checked all bolts , filled it with the antifreeze that just went in. (It was strained thru a filter. )
The engine started but was rough.  It turns out that #5 &7 wires were put on backwards.  A tiny twist on the distributor and
She started purring.  The rpms sat at around 700 instead of 1300.  All because of a $3 gasket. No leaks, No drips.  It's a good day.

The transmission is filled to capacity and shifts through the gears.  Onto the driveshaft and an exhaust.  And brakes.  And seats. And seat belts.  And skidplates.  And and and....

A few "concerns"

  The engine runs great BUT

• There is a coolant leak where the rear heater hose adaptor was screwed too tight into the intake manifold, thus resulting in a crack.  **PIC BELOW**
• The thread holes for the distributor cap are stripped on one side also.  may be able to re thread
• There is an air leak on the back side of the throttle body that is making the engine run at 1300 rpms.  It drops to 800ish when sprayed down w/ wd40.  Either the MAP sensor tube or gasket area.
• The alternator isn't charging
• The starter croaked again too.
•  The transmission cooling hose fitting is dripping when running and the rear tranny seal near the governor is dripping.  
• This is starting to get expensive

On an upnote, I tried shifting the tranny manually and it seems willing though.
The guy down the street had a manifold , distributor, and tranny dust cap that I will use to fix the engine issues.
I have heard that 95-97 chevys had coolant leak issues back there from intake gaskets not sealing. So that will be a concern putting it back together.
I guess I need to work on shifting mechanism , rear driveshaft, and redoing brake lines so it can go on a trailer and get it back to the shop to replace the seal under warranty.

***Here is the cooling leak culprit. As soon as it was unscrewed, you hardly could tell there was a crack.

Here is the valley of the engine.  Really pretty clean considering the engine was supposed to have high double digit miles.

Every nut and bolt was put in place on the new intake so not to lose it.  This engine had intake work done before, the front and rear valley seals were replaced with rtv.  The white is paper towels to keep debris out of the heads.

Tomorrow, new intake!