M135 M211 2 speed transfer case mod

[DUUANE]

Haha..roger that ..im not concerned about the parking brake bracket..as long as the upper and idler shafts/gears are in ok shape ill have something to work with..
My thoughts so far are facing some material off the rear of the input shaft sliding gear and/or moving the pto drive gear rearward. The goal would be to create an either or situation where the sliding gear drives either the input shaft driven gear OR the pto drive gear but not both.
This would move the pto drive gear in the opening in the case also so no more pto on the tcase..but we knew that already. Also i would like to create enough space if possible to have a neutral position..and try and add some detents to the shift shaft.
But..we wont know for sure till we actually get into the case.
I really appreciate your help on this Mr.Ploughboy.. hopefully there is one hiding in the weeds out here..

 

[DUUANE]

If all goes well ill be picking up a spare t-case this weekend so we can have a peek into the guts of the machine.

 

[DUUANE]

Well..better late than never..the spare tcase landed in the yard today..its gonna be a couple of weeks till i get enough time to get it up on something so we can have a look inside. A spare T138 5 ton tcase came with it so it was worth the wait.

 

[m1010plowboy]

That is good news. The brother made it to Kelowna but I'm glad I stayed behind. The snow in the mountains is a little deep this year apparently and travel has been tough. He says he's stuck there but once a guy gets to B.C., well, you know.

Check out post number 25 over here. There is a bit of spec/ tolerances info that might help out. https://www.steelsoldiers.com/showthread.php?103763-M135-Transfer-case-2spd-conversion/page3

 

[DUUANE]

GLad he made it safe..i commuted through the rogers pass bi-weekly for a couple of years before we moved the wife and boy out from red deer..had several near death experiences.

Here is the info from your other link just to condense.

"I have changed the g749 transfer to two speed several times. You need to purchase the large diameter low gear out of a g508 banjo transfer. The top sliding gear must be narrowed to 1 7/16 inch so you can neutral. Transfer case must be modified slightly for large replacement gear to fit. I have done this change over by using a hand grinder an a hand held hacksaw. Shifter fork must be turned over and base ground shorter where it slides on shaft. "


Thanks very much for this..i was really not keen on the idea of transmitting power through a shrink fit connection..if anything else related comes up please keep me in the loop.

I'll make you a kick ass coffee if you make it out this way..Armoured cow and everything! .i run a dry camp.

Cheers

Corey

 

[Ashley P]

Hey, where are the pics of the completed mods? (Kidding, of course.)

I am interested and hope you can document this stuff with some vids or pics. I've learned a lot from YouTube vids, I find that info is lacking on old subjects that don't have a youthful following.

 

[DUUANE]

Hahah ..i know..i'm sick as a dog at the moment *cough*.. i think i'd like a little better description of the G508 gear we need before i go ordering bits from the 4 corners of the earth.

 

[SCM35A2]

Subscribed!

 

[DUUANE]

Ok..so what we need now is an exploded view diagram of the GMC banjo transfer case to id the gear. I have been so far unsuccessfull searching for one..

 

[DUUANE]

Well..sometimes im like a dog with a bone.. here is a poor quallity image of what i am told we are looking for..it would be the gear labelled HH in this diagram.

Let the digging continue.

So who has a cckw banjo box with a broken case that will sell me a gear to see if this will work?

 

[SEADUCEME]

Correct , I'm about to assemble mine with a 5sp manual/2sp transfer case from a cckw. I have everything but a clutch pedal n slave/ master cylinders, next stop the salvage yard

 

[DUUANE]

What are you using for a powertrain seaduce? This thread is about converting the G749 transfer case to 2 spd operation. From what i've read on the cckw case.. i would use blue loctite and safety wire the mounting bolts.clean out the holes in the case and the bolts with brake clean or naptha before assembly.

 

[DUUANE]

Ok..so we just have to wait for the mail man/woman to walk from Italy to my place and we will have some more progress on this thread..

*twiddles thumbs*.....

Stay tuned

 

[SEADUCEME]

Yes I did read vaguely about that. I'm not in the habit of visiting regularly here yet . I'm goin this weekend 3/15/18 to pick up a 302 that's in better shape than mine then goin together, I'll prob just play it as I go , as an industrial rd tech improvising and on the spot modifications are nothing new to me

 

[SEADUCEME]

The main thought. I'm converting/ installing a 2sp transfer. I had understood wrong as you are converting a 1sp to a 2sp wich was my original route but I fell into the 5sp/2sp parts package and that was the easier way to go

 

[DUUANE]

I wish parts in good condition were more available up here for the 135/211..shipping mystery components across the continent gets expensive.

 

[metal magnet 1963]

I hope you are successful with this mod. I will be tearing one down to check and re-bearing when the time allows, but I really want to be able to use my P.T.O. and don't want to blow either up. As for using any other engine /trans to power the deuce, I have one truck here that was "converted" by someone to a four speed standard, and it sucks big time. Original engine with a manual 4 sp doesn't have much power in 1st and REALLY bites in second. I hope to demo this first chance I get this summer.

 

[DUUANE]

This mod should give a 2.63:1 low range but we will lose the use of the transfer case p.t.o.
With the added low range the possibillities for transmissions and transmission mounted p.t.o's are huge... If i can make this work...
We are all waiting on the parcel post to bring the gears..as soon as i have them in my hands we can open the can of worms.

 

[DUUANE]

Ive had a pile of chevy trucks with sm420's..i can immagine how bad my life would be trying to bang shift 2nd gear off the growler sliding 1st/reverse gear at every stop sign..then the stress of winding it up enough to get past the giant hole between 2nd and 3rd in a deuce..i always hated that ..even the sm435.Great transmissions as long as you stayed in one gear. I have a 1980 3+3 here thats going to be getting a clark 285v just so i can be rid of that. And a bigger clutch as a bonus. Hopefully itll fit without a body lift.

 

[DUUANE]

Contestant #1

Ok so i picked up the gears from the post office today..here are the pics.
Part number 3659894 from the G508 banjo transfer case.
This is supposed to replace assembly "w" from the second pic in post #5 of this thread with modifications to the input shaft sliding gear, input gear shift fork and rail, and case to allow fittment of the larger gear.
Ill be returning to the shop tomorrow night and should be able to make some time to take some pics inside the tcase this weekend.


Happy Easter