Transfer Case, Part I

Now with the transmission case relatively complete (waiting to add gaskets until the last moment prior to mating it with the transfer case and engine), it was time to pick out one of my half a dozen transfer cases to clean up.  My five year old son, Jack, will very simply tell you that the transfer case make the jeep go in four-wheel drive.  He is my secret weapon and when I get confused, he dumbs things down so even I can comprehend the most complicated theories.   One day, he and I were chatting about some old theory of Einstein's while enjoying a cup of coffee.  He pointed out to me...sorry, I am getting WAY off track right now.

Anyhow, I thought a Dana 18 transfer case was a  Dana 18 transfer case no matter when it was built (during the war or postwar).  Ha!  I have been somewhat educated in the last week or so.  Although the systems are the same, they are different.  Two major areas of difference are the postwar units had an upgraded Intermediate Shaft (went from .75" WWII to 1.25" postwar).  Also, the beefier T90 postwar transmission was structured slightly different from the WWII T84 unit.  The T90 did not need the critical golf pencil sized Interlock Plunger to rest between the transmission and transfer cases.  So, the postwar units did away with cutting out the channel in the transfer case for the Interlock Plunger to ride in. 

Well, I have several transfer cases (all needing to be refurbished!) sitting around the property, so I really liked my odds of finding the correct WWII version.  In the end, I had two; one still sitting in a dilapidated jeep in the yard and another sitting in the shed.  The one in the shed was easier to access so I opted for that one.  It originally came from the $150 crap jeep I bought locally.  But it is the GPW (Ford) case!  That is a small chunk of gold to me.

The first step in rescuing the transfer case was to disconnect it from the T90 transmission it had been mating with for 5o or so years.  I popped the rear cover off of it, finagled the cotter pin out of the large castle nut on the mainshaft.  For some reason, my 1 1/4" socket was not working.  I drenched the nut with penetrating oil and went to buy a larger socket.  In the end, I used LOTS of penetrating oil, flames, hammers, chisels, screwdrivers and some muscle spread over a week or so, but the darn nut would not budge.  It was rusted on to stay. 

I ended up taking a page out of Bubba's book.  I strapped the transfer case to my trailer, wedged a piece of steel into the gears of the transmission (to stop them from spinning), connected my socket to a breaker bar, stuck the breaker bar into an old fence pole and hung my fat ass off of the pole until something broke.  "Something" was either going to break, as in unfixable, or the nut was going to "break" loose.  I got lucky.

In all regards, this SHOULD work.  Seriously, my muscle with Jack's brains?  Easy.

Struck out with Jack, so I would I was flat out grasping for straws.

Here is the big hunk of steel wedged in the transmission to stop the gears from spinning.
 I wasn't too concerned breaking the gears.  It is a T90 transmission and I have a few of these (that I do not need).

Here is how I actually got the nut to budge.

VICTORY!

Now that I got the transmission and transfer case separated.  It was time to disassemle the case, take inventory, order replacement parts and clean all of the usable materials up.  Let's do this.

Here is the the transfer case with the major componets that I will be referring to labeled.

Rear view.

Front view.

Internal view.  You can see the gears of the Intermediate Shaft.

Front output cap and shaft (bottom left) and bottom access plate (bottom right).

Rear view.  Output shaft and the parking/emergency brake.

Parking/Emergency brake unit.

Internals.   Output shaft (right) Intermediate Shaft (center).

Inside the Main Output Shaft cap.

The nastiness of the inside of the bottom access plate.

I used a 12 ton press to get the Intermediate Shaft out.  Funny thing, on the top of the case, there is a data plate from Brown/Lipe Spicer.  The case clearly has the Ford stamping on it.  This is confliction in the highest sense!  Turns out, the Intermediate Shaft was of the larger postwar variety.  My best conclusion was that the military sent the case back to Spicer after the war to have it modified.

After getting the Intermediate Shaft out, I could then turn my attention to the Output Shaft.  That one was a bit tricky.  I couldn't finesse it out so I turned to the manual to figure out the proper method.  Turns out you  need to beat the rear end of the output shaft with a mallet.  It would then break through the races and cones of the front side and give one room to manuever.  Wow.  I never would have guessed that!  I accomplished this feat, although somewhat skeptically.  The last obstacle was a rinky-dinky little snap ring.  I ended up spreading the snap ring too far and snapped it two.  Luckily, when I was ordering my new parts, I had enough forward thinking sense in my brain to ordered a spare.  Actually, Jack told me to do it.

Output shaft on its way out!

Cleaned and primed main case.

Compare and contrast of the gears.  Can you guess which one I have cleaned?

I ordered $175 worth of replacement parts.  This consists of all of the bearings, seals, cones, races and a few other little parts.  Luckily, nothing of major importance was ruined on the inside.  Everything that is being replaced SHOULD be replaced after 60 years of use and abuse.  When the new parts arrive, I will take apart the other assemblies (front and rear caps), clean them up and then rebuild them.  For now, I am just going to clean up these parts that I am going to reuse...and wait!

Axle F(ront)- COMPLETED!

Wow, this project has been going on for several weeks and I think it is finally finished!  For awhile, I didn't think the end of it would ever come in sight.  The delays resulted from not once, but twice I failed to order the replacement parts I needed and then the final delay occurred when I couldn't get the steering pivot arms to "pop" off of the tie end rods so the proper preload tension could be set up.  Oh, don't worry, I do not talk like this all of the time.  I only just read the section in the manual that explained it all to my simpleton mind.  But enough of the chit chat, let's figure out how I got from point A to point D.  A is for Arsenal; D is for Democracy.  I have now nicknamed my garage the "Arsenal of Democracy."

The inside of the axle after all of the seals have been replaced.

Recap...I had removed the main gears out of the axle so I could replace the pertinent oil seals for the axle shafts.  The gears were then replaced after installing the new pinion seal.  Then I had to replace the fourupper and lower cones and cups(fancy words for bearings and the saucers they sit in) on the steering knuckles (the large roundish balls at each end of the axle shafts).

The old (on top) and the new (in place on the bottom).

This is how it looks with the new spindle bearing cups.

At this point, I now needed to install both axle shafts and then I could set up the steering pivot arms.  However, this is when I had a devil of a time trying to separate them from the tie end rods.  Several sources say I could beat on them with a BFH and it would "pop" off due to the tapered rod that holds them together.  Well, I beat, and beat, and beat it like it was the neighbor's red-headed step child.  This didn't work.  I even youtubed some videos of this procedure to make sure I was hitting it right.  I was.  Another source offered up a "pickle-fork", but I feared this would have destroyed my useable tie-end rods, so I opted to continue beating the pivot arms.  One day, many days into the beatings, it all of a sudden, quite unexpectedly "popped!"  Boy, was I stunned.  Nonetheless, I could now move forward.

The next, and supposedly very critical step was to set up the pivot arms with the correct amount of shims in order to get the proper bearing preload...whatever the hell all of that means.  The manual said to do it, so I was game.  I greased up the new bearings, taking great care to keep them clean of dirt and crud, and placed them in the new cups on the knuckles, then I placed the spindle housing on the knuckle and lined up the tapered shafts of the pivot arms to hold it all in place.

Basically, the pivot arms that hold the steering rods connect to those cones and races that I replaced earlier.  Depending on how they were manufactured (thickness and height) one needs to either add or subtract shims beneath the pivot arm to set the proper amount of restriction in its movement.  The manual says to start with .048" of shims on the upper and lower pivots for each side of the axle.  Then, one must measure the pounds of pressure needed to make the pivot arm move the steering knuckle.  The idea pressure is no less than 4 pounds and no more than 6.  In order to achieve this specific rating, more or less shims are required.

If you are raising your eyebrows right now (because you understand what I just wrote) I cannot fault you.  I certainly raised mine SEVERAL times.  No way could these little shims make any difference.  At one point, when I couldn't separate the pivot arm from the tie rod end, I thought about skipping this step.

Meauring the thickness of one of the shims. 
Behind, on the work bench, are other shims of various thicknesses.

This size shim ended up being the shim of choice in order to obtain the proper amount of spindle housing tension.  Ironically, it was within .005" of the shims I removed during the teardown.

The shim pack came with multiple shims in 3 or 4 different widths.  I started out with the required combination of .048" thickness, but when I tested the tension, it was practically non-existent.  I was working on the shorter axle side and when I disassembled it all originally, there were no shims present.  I seriously thought again, "Let's skip this nonsense."  However, I tried one more time, reducing the amount of shims upper and lower.  At this point, it was kind of like a trial and error exercise, however, you needed to keep the shims in the same thickness for both the upper and lower sides.  So I loosened the nuts and gently rapped my hammer on the base of the pivot arm and it slowly made its way out.  I reduced the shims and put it all back together and measured.  Sure enough, there was a bit more drag present.  Wow, it was actually working!  This process when on a few more times...too much, too little and so on and so on.  Finally, I got the right combination.  I ended up using one shim for each mount and it was the one pictured above: .0105. 

Ironically, on the long axle shaft side, there originally was a shim in place.  It measured within .005" of the new one I ended up installing to give it the correct tension.  I still have to fill the internals of it all with grease.

Checking the pivot arm tension.  The camera flash was too bright, but it reads 5.5 lbs when the pivot arm began to move.  The manual gives a range of 4-6 pounds, so this is within spec.

With both pivot arms in place and correctly mounted, I could now put on the rest of the steering gear.  Easy peasy.  Lastly, I lubed up the axle cover with some sealer, smeared it on good and messy, placed the gasket on and then sealed up the main pumpkin.  All it needs now is some oil.

Next comes the spindle, which fits tightly into the housing.  When the brake backing plate gets screwed-in, the screws go through the backing plate, through the spindle and tighten into the knuckle housing.  The sneaky part is tapping the spindle into place, yet keeping all of the screw holes lined up.  To do this, I stuck the screw into the spindle, lining them up with the house and turning them in a few twists.  Then I rapped it gently with a hammer to wedge it into its final spot.  The screws were removed and the brake backing plate was then installed with the screws going into their final resting place.

Spindle cap held in place with loose screws.

The brake backing plate in place over the spindle and all screws tightly in place.

Most of the remaining steps are almost identical to what occurred with the rear axle as far as installing the brake shoes, adjusting them to the drums.  Also required are new seals for the drums, and if required, new bearings and grease.

BEFORE.
I love "before and after" shots.

AFTER!
Both sets of brakes shoes in place.
 (I cheated,though.  This is the driver's side.) 

With both brake backing plates with brake shoes and wheel cylinders in place, the next step is to install the brake hub.  However, before this could be done, I had two more oil/grease seals to replace on each hub.  Also, there are a pair of wheel bearings inside of each hub.   After popping out the seals, I could then remove the bearings.  I cleaned each bearing up (removing what Jack calls "nasty old grease") and then I could inspect them for over-heating marks and individual worn out bearings.  They appeared satisfactory so I packed them solid with new grease, put them back in place and then "gently persuaded" (with a hammer) the new seals.  Hubs installed!

Both hubs with newly grease-packed bearings and new seals (in the center of these metal donuts). 
The red gunk is the new grease.

These large washers go between the big nuts that keep the outer wheel bearings on the brake hubs in place.  The broken washeron the RIGHT came out of the front axle.  The washer on the LEFT is a replacement washer I pulled from an old, nasty post-war jeep chassis in my yard.  I was saddened that I couldn't use my original "F" marked washer.  However, my Christmas Miracle happened in during the Ides of March...the washer I pulled from the post-war chassis was "F" marked, too...An original WWII Ford part!  It is hard to see, but if you look close enough - like put your nose up to the computer screen close - you can identify both "F" marks at the 12 O'Clock high positions.

Both brake hubs installed.  Two more steps to go.

 After adjusting the brake shoes, the last major project to address is the grease seals that sit behind the steering knuckles.  The new seals are a slightly different set-up than the originals.  Albeit a better set-up, they do look slightly different when installed.  In an effort to take advantage of newer technology, yet keep the 1944 look, I modified the original steel plates (which kind of broke my heart) to retain the right "look."

The newer style pressed steel plate (L), the original unmodified plate (C) and the modified original steel plate (R).  Can't see the modification, can you?   Look closely...there is a pin located at the 12 o'clock, 9 o'clock and 6 o'clock positions that must be ground smooth in order for the plates to fit snug against the felt.  Pins are visible on the center plate and have been removed on the right plate.

The seal all assembled.

The only major difference between this set-up and the original style would have been a second set of gray plates mounted behind this one and they sandwiched together the grease seal.  This style has a rubber seal mounted tightly against the knuckle ball joint, then a piece of thick felt and then the original steel plate holding it all together to the knuckle. 

My inspiring mental moment occurred when I was fitting the seal on the long side of the axle.  I had forgotten that when I removed the original, there were only 7 of the 8 bolts present.  Well, when I discovered that fact, again, I felt a bit of dispair.  "Oh, this sucks...gotta go to Lowes for one lowsy bolt to finish this project."  And then, that energy saving light bulb in my head began to emit light.  The light got brighter and brighter and then I realized I was forming a thought.  "Duh, you've got a junkyard outside.  Go get a nut from one of those buckets of rust!"  And that is what I did.  I pulled the correct sized nut off of the old M38 front axle.  That way I wouldn't have to chase down another nut for the next WWII jeep!  That was totally a two for one thought.

All assembled, front view.

All assembled, side view.

I'd like to claim El Finito at this point, but it is fairly obvious that I still have some painting to do.  Internally, I need to fill the pumpkin with oil and the knuckles need some grease.  The grease zerks on the steering arms need a shot of lube, too.  (That lube is for you, J2).  I still need to tighten the two tie rod end castle nuts and the pinion nut.  And I just remembered that I need to pull both axle flanges off and bend the lip of the outer washers over the edge of the outer nuts.  Yeah, quite the punch list.  I'm done blogging about this beast, though.  Next time you see it, it will be mounted to the frame!

(Trans) Mission: COMPLETE!

If you will recall, this transmission was already disassembled when I purchased it and I had to inventory all of the parts to figure out which ones were usable and which ones were AWOL.  I spent an afternoon in the garage with a caliper, a few different manuals and the internet trying to figure it out.  Once I had it all labeled and a wishlist written out, I ordered the parts and waited.  Well, they arrived and it is now time to assemble this steel jigsaw puzzle together.

Cluster gear and washers installed and being held in place with a temporary steel tube.



The first step was to gently persuade the new cluster gear into place.  The old one had one too many chipped teeth for my faint heart.  It is now a sturdy paperweight on the workbench.  On either end of the cluster gear sits some assorted brass washers.  I put a few dabs of grease on the washers in an attempt to hold them in place while I fitted the cluster gear into the box.  Then I used my faithful steel tube (that was used to punch out seals in the axles!) to hold the cluster gear and washers in place while the remaining parts of the transmission are to be installed.  Funny thing is, if I were to place the proper shaft through the cluster gear now, I would not be able to fit the remaining gears and shafts into their proper places.

Next step is to assemble the main shaft.  This consists of placing (in specific order) the retainer ring, two gears as well as the assembled synchronizer and another snap ring to hold it all in place.  Quite often it is the synchronizer that fails, thus shift issues when driving develop prominently with the second gear.  I think this is an issue with my "good" jeep and will be addressed (hopefully) during a future rainy day.  Anyhow, in my new small parts kit were replacement parts for the synchronizer so this transmission shouldn't have this problem.  I'm sure it will have its own set of issues, anyway.

Note the assembled main shaft in the lower part of this picture. 
Also scattered about, in somewhat organized chaos, are the remaining bits and pieces of the transmission.

The main shaft slides into the upper part of the transmission and sticks out of the rear of the case connecting it to the transfer case...which Jack will tell you makes the jeep go in 4-wheel drive...and he is correct, too!  With the main shaft in place, the input shaft can now be assembled and will slide onto the front part of the main shaft. 

There were a couple tricky parts for the input shaft.  The first obstacle to hurdle was getting all of the roller bearings in their proper place internally.  My friend, Greasy Bob, (not really, more like just the grease minus the Bob) came in handy here.  A little dab of grease and the assistance of needle nose pliers works miracles.  Thirteen little tube-like bearings have to form a perimeter for the main shaft to slide into.

The thriteen little tube-like bearings (on the right) need to be placed perpendicularly inside the input shaft (being held).

Disco tech:  Bearings in place.  Thank you Greasy (Bob).

Now it is time to slide the assembled input shaft (it has a larger bearing with snap ring, gear, and synchronizer blocking ring) into the front of the transmission box and mate it up with the already installed main gear.  This is the second tricky endeavor.  The shaft has to go in through the hole on the front of the transmission case, clear the cluster gear sitting on the bottom of the case, mate up with the main shaft (without knocking the thirteen little bearings down) and have the synchronizer blocking ring (brass rings on both sides of the synchronizer) in their required positions.  Over the river and through the woods with low lying branches at a full on trot/jog...because I don't run.  This took a few attempts, but it finally worked out.

Attempt No. 1:  no good.  The brass blocking ring on the right is not snug enough to the synchronizer assembly.  Turns out I did not have the synchronizer deep enough on the main shaft.  So that was why the snap ring didn't fit properly?  Huh.  Everything came out and the mistake was corrected.

This might have been attempt 7 or 8, but finally I got it right...I think.  Input shaft is at the top, output shaft is at the bottom.

Now, the entire case must be flipped upside down and the steel tube is to be removed and replaced with the proper cluster gear shaft.  The process is kind of like a magician pulling a table cloth out from underneath the settings.  The shaft must slide through the holes without letting the thrust washers fall to the bottom of the case.  If this occurs, it is back to step one...after disassembling it all!

First attempt:  flipped, removed, installed and locking plate in position for the final tapping. 
I actually may have read about this in the Kama Sutra book.

With the shafts in position, the next step is to install the shift rails.  Two actual shift rails which run along both sides (like a set of railroad tracks) and a smaller rail will be placed to hold the shifting forks.  Yes, dinner and a show, folks.

Skinny rail and two shifting forks in position.

Now it is time for the pair of shifting rails (the railroad part of the equation).  The fun part of this procedure is to put in AND keep in the tiny springs and poppet balls.  In a split second, the poppet balls can (and will) shoot out and fly all over the garage like a bb pellet on steroids.  Nice.  Happened twice.  Lost and then found my balls.

Both poppet balls are sitting on their respective springs next to the holes that they will be placed. 
Shift rails are in position to cover up the poppet balls. 

The shifting rails both run south to north (in the ablove picture) in the transmission box.  They have tiny grooves cut into them that will slide across the top of the poppet balls.  The springs will apply pressure to the balls which in turn will apply upward pressure on the shifting rails, thus helping to keep them in place and your vehicle in gear.  So, the tricky part is keeping the poppet and spring compressed while you slide the shift rail across the top of them.  A third hand would have been downright awesome.  A fourth hand could have patted me on the back, consoling me after shooting the balls across the garage.

When I was cleaning up the case before I began this assembly, one of the poppet balls were stuck inside the cavity.  I couldn't recall which one it was.  I guessed and inside this cavity I placed my new poppet ball and spring.  Well, it turns out that I guessed incorrectly.  It was the left hand cavity that had the ball stuck.  I know this because I place my new poppet ball in the right hand cavity...and the poppet ball in the left was stuck...again.  Well, it was a pain in the arse removing it with all of the gears in place.  However, with some clever finagling and duct tape, I was able to dislodge it without losing it.  I replaced it with another poppet ball and I instantly could feel the pressure on the rail.  This is good.

Both rails in place and poppet balls and springs are doing their job.

Cover, retainer and old throw-out bearing installed.  Extra parts in the background?!?

Now, one might ask, "Bo, why would you have painted your GPW transmission case Ford tractor gray and the cover with OD?"  And I would reply that I could not find any GPW markings on the cover, so it must be from an MB and MB covers were painted OD, not Ford tractor gray like the GPWs.  Also, please note that the cover and front retainers are setting in place.  I still need to install the required gaskets (in picture above) as well as replace the clutch throw-out bearing (big steel donut on the middle of the input shaft in the picture above).  As for the other extra parts pictured...I bought some duplicates...just in case!

Since you made it this far, wanna see something else?  Sarah says it is probably pornographic in my head...

This might have to be my "happy place."  Yes, they ARE building jeeps...back in the early months of 1942. 
Thank you to ewillys.com for finding this gem!

Now, onto that never-ending front axle.  The only things stopping me from finishing that project and installing it this weekend are my fantastic wife, my two kids and Tiger Woods PGA Tour 2012 for the Wii.  And not so much in that order.