D20 Front Yoke Nut Stuck Any Ideas?

[68 Broncoholic]

When I pulled the NP435/D20 out of my 74 I decided to change t-case's (had 2 spares) cause the one that was in there was hard to shift. I found out (after t-case is installed) that the front Yoke on the repalcement D20 has the old 1-7/8" wide bolt pattern Yoke instead like the standard Spicer 1-1/2" I have drivelines for.
No problem, I'll swap yokes from the one I had in there.
I took the Spicer yoke off my old D20 sitting on the ground but couldn't get the old style off the replacement D20. I tried a 4' cheater bar after the impact gun couldn't do it. Then added some heat and pennitrating fluid. Then I tried driving forwards with the bar wedged on the frame and that wouldn't do it. Any other ideas? This nut must be rusted or installed with green or red lock tite.

 

[ugly74]

dumb question, but it's not left handed threads is it?
I dunno, never had to change one.

I've been in similar spots with equipment at work...
ended up blowin the yoke off with a torch. after packing "heat sink clay" around the base, and the front of the case. it's tricky work, but doable.

 

[68 Broncoholic]

No its not reverse threads on a D20 t-case.

So you cut off the yoke and replaced the output shaft?
I do have a spare D20 I can play with but man that sounds like lots of work. If the case was on the ground I'd do it. Its sounding easier to get a new driveline and keep the yoke thats on it.

 

[ugly74]

no, I cut just the yoke off, and left the splined shaft. I ended up having to chisel the last few remnants off. but I can't recall on a D20, if there's anything in the way, to keep you from bein able to get at the whole yoke.

even if you can just blow off enough of the yoke, to be able to torch the nut off, that'd be easier. touchy precision torching is easier on a threaded shaft, than it is with splines.

but since you'd probably rather keep the larger yoke (I would)
I'd try this stuff called "Break Free CLP"
it's actually a gun oil, but I use it on everything. makes WD-40 look like super glue. let it set a couple of days.
If you doubt your ability with a torch, don't try it. I'd hate for you to ruin something and be all POd at me.

 

[68 Broncoholic]

Naaa, I'll just search you down. hahaha!!

Yeah, I think I'll forget about the torch idea for now and keep workin at the pennetrating fluids and get a 8' cheater bar! If that fails I'm gunna bite the bullet and buy a new driveline.

 

[ugly74]

you'll get it off of there. I'm serious about the CLP! it's excellent stuff.
anything designed and tested by the military can't be all bad.

 

[bax]

put a big pipe wrench on the yoke and a socket and breaker bar on the nut. Get pipe for both bar and pipe wrench. You will need a friend,one on one pipe the other on the other pipe. If this fails, heat the nut and repeat. It will work. 6 point socket only.

Bax

 

[Wes harden]

Also another spay that works very well is Mopar rust penetrant, developed to keep the heat riser valve free on oldies.
Break free is good stuff too, all my firearms get it

 

[68 Broncoholic]

I'll give that a shot. When a t-case or axle is out of the truck I use a pipe wrench on the yoke so it doesn't spin. Maybe this will give more leverage.

 

[mag409]

Did you try running the impact forward first? Sometimes you can bust it loose and then back it off.

 

[68 Broncoholic]

Yeah, I tried that.

 

[welndmn]

Are you using a shallow or deep socket?
using a shallow with no extension gives the most power.
What kind of gun? May different models make differnet power.
If you give up, find a local shop that does a lot of imports. A tech there will have a 3/4 impact (those do 1200 ft) and I am sure someone will remove it for a case of beer.

 

[evil69]

Are you using a shallow or deep socket?
using a shallow with no extension gives the most power.
What kind of gun? May different models make differnet power.
If you give up, find a local shop that does a lot of imports. A tech there will have a 3/4 impact (those do 1200 ft) and I am sure someone will remove it for a case of beer.

Why would a shop that does imports have a 3/4 gun? I would think a heavy truck/equipment shop would have one. Not saying your wrong, only asking.

Have you tried bumping the regulated air pressure to the gun a little? Tried heating nut and let the gun beat on the nut for a while?

 

[72Sport]

Squirt some oil in the air fitting at the impact wrench, may increase torque.

Remove anything from the air supply line that restricts flow.

Use your largest dia and shortest air line from the compressor to the gun to increase flow and pressure at the impact wrench when it is running.

Get ready to fire up the torch in case none of the above work.

 

[welndmn]

Why would a shop that does imports have a 3/4 gun? I would think a heavy truck/equipment shop would have one. Not saying your wrong, only asking.

Have you tried bumping the regulated air pressure to the gun a little? Tried heating nut and let the gun beat on the nut for a while?

Timing belts, when I wrenched 90% of the crankshaft bolts on imports were siezied in place, and in order to get to them you have a 3' extension on a 1/2 drive impact and it left no power. Tossing s 3/4 gun it blew it away.

Most Tractor and big rig shops in my area are very busy and charge a lot an hour where they can't spare 5 mins.
Import shops are slow, those are cars don't brake down.
(I was a Honda tech, before going to Fords)

 

[evil69]

There ya go. I thought there was a reason. I know the tractor shops are busy, but they are car guys like us for thye most part and may be willing to help.

 

[68 Broncoholic]

Thats a good idea. I might drive down to a local shop and see if a 3/4 impact will do the job. Sucks cause I have the windshield out (painting soon).
The local cops have a thing for me ever since I decided to drive my 68 around town... %)

 

[Solar Aviator]

Before I got the torch out I would try to drill two holes 180 degrees apart into the face of the nut in the axis of the shaft. Center punch the hole locations and pick a drill with a diameter a little less than the wall thickness of the nut. A chissle should split it loose. *#$%, &^#*, and &@#$ may also help!

 

[68 Broncoholic]

Another great idea, thanks!

I'll see if I can get some time tonight and giver another shot.