Project: Old Guard - lots of pictures

[Master Yota]

Its been six weeks since my last confession, so I figured an update was in order.

First of all, anybody considering doing a dual tcase setup using a single married case, and a divorced case behind it; change your mind and heed my words - Save your money for a doubler! The amount of brain power required to make this work is more than surprising, its painfully criminal! But I've made headway, not enough to have it installed under the truck yet, but it has been test fitted into place. Its seems that every time I crawl under the M37, I manage to invent a new problem to solve. Anyway, I'll let the pictures speak for themselves...

Here is the finished mount. The Tcase mounts are done, but the frame mounting points needed some attention.


I had to cut off both the front mounts to narrow them, and redesign the setup to match the rears. I sleeved the tubing with a solid slug and welded it in place.


Then I used a small piece of scrap tubing to sleeve the outside so that it would match the diameter of the remaining tubing, and then welded them in place on either side.



After getting the mounts welded on, I had the empty framework again under the truck, only to discover that I needed to lower the setup so that it wouldn't hit the floor under the cab. I fabbed up four spacers from 1.5" square tube to space the mount downward (thats what the yellow blocks are on the framework).


Heres the setup is going into position...



Gotta love milk crates - (Diff jack - balanced 2x12 - balanced milk crate - balanced 2x6 - all balancing 200lb. NP205 and mount setup!)


It was at this point that I determined that with only 7" between the D20 output, and Np205 input, there really wasn't enough room to put a jack shaft between the two. Unfortunately I couldn't move the 205 further to rear due to a very massive crossmember in the way... (Or could I?)

Now you see it, now you don't - due to the fantastic science behind a plasma cutter, the offending cross member is no longer offending me... I will build a new crossmember once the tcase and rear end is installed. I need to ensure that the crossmember won't interfere with the drive shaft...


Thats as far as I've gotten to actually mount the setup under the truck. I had to pull it out again to make a few modifications and design some shifter brackets for shifting the 205.

Here is the first bracket, its just 3/16ths x 2" angle iron that I cut, bent and welded to follow the general bend of the tube.



Here it is welded and installed on the tube.



If you're wondering how its going to shift the 205, I've decided to forgo the typical rod and linkage setup for shifting and use a cable setup instead. Its easier to mount the shifters, and I won't have almost 15' of steel rods under the truck to get damaged or bent... Once my other shift cable shows up, I should be able to finish mount the setup, and move on to bigger and better things, like the rear end!

Lastly, I had to build a plate to mount the parking brake lever to on the side of the transmission. Its just 3/16ths plate, and it ties into the top cover on the trans, and a trans case hole. I also put some adjustment holes in the plate so that I can angle the handle a little so that it dosen't interfere with the bottom of the dash, or the openning in the floor access panel.

[windage]

Fantastic...my head is spinning trying to keep up with the issues you find and fix...keep it up..

[M37UK]

"If anybody see's any stock parts they are in need off, I will not be reusing alot of this stuff. Just ask and I might have what you need."

I would be interested in the vent pipes from the carb elbow to the distributor and the fittings that go with it........!

Cheers

[Master Yota]

So, as usuall, my deadlines seem to get pushed further and further back while I wait for parts. Nothing strange about that. Its been 3 months now that I've been working on getting the second tcase under the truck, and that still hasn't happened yet. I've been waiting for my second shifter cable to come in so that I can finish the shifter mechanism's before the unit becomes "difficult" to work on under the truck. So to use some of the time wasted while waiting, I've been working on the floor, as it needed some attention due to some clearance issues.

I had to modify the curvature of the transmission floor panel near the seat, as the original floor there curved downward and interfered with the top of the Dana20. The easiest way for me to solve that issue was to cut out the floor section, and flip it over 180* and weld it back in. That would have been fine, save for me getting a little over zealous with the plasma, and cutting the floor panel too narrow to meet up with the floor at the seat riser, and the leading edge of the transmission panel openning. (I can make excellent scrap from anything...)

Here is the openning of the floor after I cut it.


I used the now scrap piece of the original floor as a template to hand form a new wider floor patch with the same curves from some 18ga. sheetmetal I had leftover from another project. I clamped the two pieces in the vice, and formed them by hand, with just a little persuassion from a hammer and dolly. I was quite happy with the fit.


Here, I've laid the transmission cover bolt flange (which also needed to be cut off and flipped over) over top of the new floor panel to get a rough idea of how the two will fit, and where the bolt holes will go. I cut the original welded nuts off the old floor piece and welded them to the new panel so that everything looks and works in the same way.


Here, the trans. panel is in the vice being trimmed out for the transmission shifter, and the twin stick shifters for the D20.
Its evident where I cut the bolt flange from on the bottom of the panel, left side.


Here the new panel is welded into place and the transmission panel is being test fit. I had to clearance a fairly large section of the trans. panel for the shift linkage to clear. Not a problem though, as I ended up reforming the panel anyway to match the new floor, and then filling alot of it back in as the clearance issues are no longer there.


I'll post some pictures of the panel when the reforming is done. In the meantime my welder decided to take a vacation, so I'm stuck doing other things while I await spare parts...

A pair of other goodies showed up in the mail though...



The price was too good to pass up...

In the meantime, while I wait again, I'll put the Corporate 14 bolt together, and get the original rear diff out from under the truck.

[paul]

nice chromo!

[Master Yota]

Here's the "other" stuff I've been amusing myself with while I await welder parts...

Ripped into the 14 bolt - started with removal of the wheels hubs and such. The C14 is super easy to work on, a nice change for once...
Stripped down to the spindle, just pull the axle, and remove the bearing hub, just like a front diff.

Pull the 4 bolts and tap the backing plate with a hammer and it comes right off.

After some light cleaning, I decided to test fit the Disc brakes. The brackets are from Great Lakes offroad, and fit like a charm


Next its time to separate the brake drum from the bearing hub; on this vintage of axle, the drum is behine the hub, and held on with the wheel studs. I used a big brass drift, and a BFH to drive the studs out, but a press or air hammer would work too.

Once the studs are out, the drum separates easily.


Afterward, its just a matter of installing the disc onto the bearing hub in the same position as the drum, and bolt everything back on. I used two studs to hold it all together for test fit, but I'll be replacing all the studs with new hardware. Then I installed the Caliper to ensure everything fit.


This swap is very affordable, and is cheaper to upgrade to the disc brakes, rather than rebuild the drums.

On to the guts... I had to regear the C14 to match the D60 front (4.56) so I started with pulling it all out, and doing a clean and inspection.
Here the carrier has been removed (after marking the bearing caps for orientation and location), the ring gear has been separated from the carrier, and the case halves have been parted allowing access to the spider gear assy.

I've removed the spider gears and swapped them out in favor of a mini-spool. Spools are a love-hate sort of thing when it comes to on road driving, I've driven one for years, and I like 'em.





Looking closely in the center of the picture, you'll notice two dots on the carrier, one on each half. I did this so to mark the carrier to ensure that it went back together in the same orientation that it came apart. The inside of the carrier is also marked with two large arrows that line up as well.

And here's the carrier re-installed in the axle with the new ring gear and spool.


The nice thing about the C14 is that the pinion installs from the front, so making adjustments is as easy as removing six mounting bolts, and then taking the whole pinion support out and just shimming it. Piece of cake.
Here the support bolts are out, and the large pinion nut has been removed.

This is the housing with no pinion support in it. The third pinion support bearing can be seen, its a light press fit into the housing.

This is the pinion support and bearing setup on the table. The pinion bearing are inside the pinion support, and the bearing are a light press fit on the pinion. It came apart very easily once I chucked it up in the press.


The C14 uses a crush sleeve design to set the pinion bearing pre-load. As I don't have the tooling to acurately measure the 350ftlbs. of torque needed to tighten the pinion nut to, I farmed this part of the assy. out to a local gear shop. I had it back in an hour, and it only cost me a case of beer. Another reason be-friend the guys behind the counter...

(Anybody notice the pinion size difference between the old and the new? The old gear set was 3.42's! compared to the new at 4.56)

As usuall, the Yukon gears set up with a nice pattern too


I'm hoping to have the rest of the rear end back together, and maybe even under the truck this weekend if all goes well...

[M37UK]

Interesting stuff, keep up the good work!

[SOTVEN]

WOW MASTER YOTA. MY HEAD IS STILL SPINNING FROM ALL THE WORK PROGRESS AND INFORMATION. NICE WORK INDEED

[Master Yota]

Thanks guys,

The old rear end is out, and the new is ready to be slung underneath any day now! Pictures will follow as usuall!

[Master Yota]

The 14 bolt is under the truck now, and it went very easy. I'd been avoiding the job of wrestling the heavy unit under the truck to test fit where it needed to go, and then back out to put new spring perches on. Turns out, my laziness was all for nothing - the spring perches lined up with the original springs! Bonus!

All I needed to do was narrow the perches on the diff from about 2- 1/4" wide down to 2" wide so the ubolts would slide past the perches. I was even more surprised to discover that the original Ubolt plates fit the 14 bolt tubes like they were designed to go together! Saved a little time, and some money on this swap! All thats left will be to shim the pinion angle once the tcase is in. I've left the ubolts loose for now, but they are tight enough to hold everything in place.

Here the old diff is out, naturally the center pin in the spring pack was broken. I replaced it.

With the truck stuck on the hoist, its at an odd-ball height, so sometimes a little creativity is needed to get parts back together...


This is the clearancing needed on the spring perches.


This shows the ubolts clearing the perches after clearancing.


Here's a shot of the 14 bolt under the truck, not a great angle, buy you'll get the idea.

Here are the disc brakes installed on one side.

Here is the 2.5" wheel spacer that brings the trackwidth back out to stock (72"). I don't really care for wheel spacers anymore, but as I couldn't find the 72" wide 14 bolt that came from the delivery vans, I had no other viable option for keeping the 18.5" wide tires from rubbing on the inner fender. I will make sure to check them regularly to ensure the fasteners are tight!


Now I can concentrate on getting the tcase in, as my parts for the welder have shown up, and been replaced. Nothing exciting picture wise, just a few shots of the tcase cable mounts, and the brackets that tie the cables to the shift rails...

Here's a topside view, the two cables in black activate the shift rails, while the third cable (with the spring) activates the parking brake.


The tie plates from the cables to the shift rails are 5/16's steel plate bent at a 90* angle (scrap basically...) They are welded to the end of the shift rails.


Thats all for now, tcase should be in this weekend...

[Master Yota]

Yay! the Np205 is finally installed! Managed to find some time and get it permanently mounted under the truck!
Now I can move on to stuff that dosen't require me to be a contortionist under the truck. Now I can contort under the dash!

Looks like the rear drive shaft will be approx. 28" long, the front will be about 48" long, and the jack shaft between the two tcase's will be 9" long... Longer than I'd expected for the rear, and shorter than expected for the front. Rear driveline angle is still to be figured out...

[Master Yota]

Not a whole lot of updates since I've been burning the midnight oil, trying to get this thing done for May, so here's a few shots of whats been goin' on...

Now that the floor is done, I turned my attention to the throttle pedal. I wanted to keep the old one, but it was more hassle to make it work than it was to re-appropriate this used GM pedal assembly. The pattern even matches the brake and clutch pedal closely enough to make it all look right. I had to adjust the bends in the pedal, and trim the floor mounting plate, but it fits well, is in a comfortable position, and has enough movement to make the throttle operate normally. I used the bungee cord in the picture to simulate some pedal pressure when I was testing for the location.



I also finished the cable shifter installation for the NP205. It shifts just like a normal stick setup, a little stiff, but that can be adjusted with some cable tuning. I cut down two stock shift levers to use as the shifters, and then bent them to match (as close as one can with 5/8'ths rod!) I used some 1/2" i.d. steel hydraluic tube inserts from PA as pivot points, welded to the bottom of the shifters. A small piece of 1/4" plate was welded to the shifter to better support the pivot and lever, as well as provide an attachment point for the 1/4" clevis that connects the cable to the shifter.

(For anybody considering a cable shifter setup using the Princess Auto control cables take note: the cables do not match the listing in the catalogue! The ends are metric M6 thread, not 1/4" NF! I couldn't find M6 clevis ends anywhere in town, and ended up modifying a set of 1/4" ones by drilling out the threads, and then welding an M6 nut to the end of the clevis).

Here is the stock shifter, getting ready to be chopped and formed...

Both shifters after some paint. I welded new bolts to the top of shifter to accept the shift knobs I had. The original shifters both had different knobs...

A closeup of the clevis attachment point

One clevis yoke about to get the M6 nut welded on...


The mount for the shifters was built out of 1/8" plate. The cable mounts are 5/8" holes and the shift lever bolt is 1/2". The mounts attaches with 5-1/4" bolts and 2-3/8's bolts from underneath.



Here's an installed shot of my "forest of levers".... (I really do think that 6 is enough).


With the tcase all wrapped up, I've been focusing on the steering and some additional plumbing and cooling.

I've tapped the saginaw steering box for hydraulic assist using the readily available info online. For the front cap, I ordered a machined aluminum cap from JK offroad. The cap fit like oem, and has the hydraulic port machined into it already. Aside from needing three hands to install it (the big snap ring is a real pain!) I would highly recommend this route, rather than trying to weld or tap the stock cap.
Here is the cap, both sides compared to the oem unit.




The second port must be drilled and tapped in the aluminum top cap of the box. Its a straight forward job to remove the cap and then measure for drilling and tapping.
The cap removed.

Here is the cap and shim on the bench. Drill the hole in the relief area in the underside of the cap.

Here you can see the pilot hole. 3/8" NPT needs a 37/64" hole for tapping.

No pictures of the tapping process, but here is the completed unit. The new ports will now provide flow to the hydraulic ram to allow for turning left and right.

I also managed to get the highsteer arms installed on the D60.


With hyraulic assist steering, more strain is put on the pump, so a good cooler is needed. As the M37 has lots of room behind the grill, I decided that if a little extra cooling is good, than alot must be better.
Here is the auxilliary electric cooling fan, the PS cooler, and an Engine oil cooler. It should all help to keep the BBF happy...



Thats all that is picture worthy for now. I've since started on the brake and cooler plumbing, and should finish up the steering early next week. In the meantime, I need a nap, as I'll be up till 3am...

[Lifer]

All those control levers (shifters?) really ought to intimidate any potential thieves!

[Master Yota]

All those control levers (shifters?) really ought to intimidate any potential thieves!

It looks more intimidating that it really is. Kind of reminds me of a bulldozer from the 60's - pick the right lever and it should do what you want! I'm happy with the location of the shifters as well, they fall within easy reach of the driver seat, and the only one that I need to lean over for is the parking brake, which is in the same location as stock.

[Josh]

Ray, the Crew needs an update!