transfer case

[nate-gk]

I am having problems with my t case. I belive Its the origional that was mated to the three speed. I am running a chevy 350 and sm420 in a 69 fj40

It might just be me but it seems loose at the point where the t case lever conects to the case. I can hear it click but the front driveshaft wont disingauge.

the H/N/L pattern confusses the hell out of me what is the proper operation for the t case. It says somthing about pulling the stick up before you shift it but i have never noticed a difference pulling up or just pushing it forward. It has very little resistance.

 

[nate-gk]

maybe i should refrase that.

Is this t case loose(in normal condition)

And what are the normal procedures for getting into and out of 4wheel drive.

I cant seem to get the front diveshatf to disingauge.

 

[zuluzeugma]

I cant seem to get the front diveshatf to disingauge.

Unlock your hubs...

 

[Poser]

Is this t case loose(in normal condition)

Do you mean that the shifter mechanism is ‘loose’ or that the transfer case assembly is loose and moving on the adapter?

 

[nate-gk]

my hubs are free.

and It seems loose when you push the stick back and forth. It just seems like there should be more resistance. But i can hear it clicking when I move it from l to N.

See what I dont get Is that it just says high and low there is no two high/ four high/ four low. Where is 2 high. Do i just put it in N

I know I am sounding like a couplete newb here but I have only had late model trucks. Sorry. And thanks for the help.

 

[amaurer]

Give the FD knob a try?

 

[nate-gk]

where is that the glove box directions say somthing about that FD knob. Where and what is this knob. my cruiser is not yet complete it runs but isnt 100% yet so maybe i am missing a crucial part.

 

[amaurer]

where is that the glove box directions say somthing about that FD knob. Where and what is this knob. my cruiser is not yet complete it runs but isnt 100% yet so maybe i am missing a crucial part.

I'm out of my element here, but I think its on the dash.

The FD knob operates a vacuum actuator on the TC that enables/disables the front drive. If the knob is missing you need to find it, as well as the vacuum lines, and maybe even the actuator itself.

I have no idea what any of that stuff looks like, only read about it.

 

[nate-gk]

OH NO vacuum lines and accuators dont sound like fun. I will do some recon tommorow and see if that fixes it.

So if I am understanding this right If I dont pull this FD knob I will be in Two wheel dirve and I can select Two high and low thru the t-case lever which is in the floor. Then by activating this FD knob I am in FOUR wheel drive and can select High or low with the t-case lever.

Should i have t case in neutral when I Press/pull this FD knob.

 

[Seth_O]

In my '69 FJ40 there are two components required to engage the front drive-shaft, and you need them both to power the front axle. 1) the transfer case must be in either high or low, not neutral and 2) the front output shaft has to be engaged.

For me the high/low/neutral selector is an arm under the dash (becoming a stick on the floor on later models) and the front output shaft is a knob (on a pull cable) under the dash that actuates the vacuum system for the four wheel drive. The two systems are totally seperate, and operate independently of each other.

Sounds like at a minimum your front output shaft is engaged either because the vacuum system has been activated, or because the actuator inside the t-case is stuck in the engaged position.

 

[nate-gk]

thanks alot for the input. I will try to sort things out.

 

[Coolerman]

Pic one shows the location of the FD pull knob and the light on the dash that should light up when the vacuum actuator is activated.

Pic two shows the vacuum actuator on the t-case.

Pic three shows the FSM pic of how it all works.

When you pull the knob you activate a vacuum switch valve that applies vacuum to one side of the diaphragm in the t-case vacuum actuator. This forces the actuator to move a collar in the t-case that ties the t-case output shaft to the transfer front output shaft that the front drive shaft bolts putting you in 4wd if the hubs are locked in.

 

[nate-gk]

all hail cooler man. Thanks a ton for the diagram. PO switched to floor shift and ditched the whole vac setup I think I should be able to figure it out now that i know how the original system worked.

 

[rsc71]

that is why the diagram plate dosnt make sence.the 3spd shifters do have some side to side play in them

 

[nate-gk]

I don't have the three speed anymore, I am running a 350 into an sm420 into the stock three speed t-case. The PO switched from the vacuum actuated t-case to floor shift. If i am looking at the diagram right, i need to put in another stick to switch the front drive shaft on and off. I am going to go check it out tomorrow because my 40 is not at my place its at a friends (i live in an apt)

 

[Poser]

that is why the diagram plate dosnt make sence.the 3spd shifters do have some side to side play in them

Especially when you have the vacuum controlled transfer case shifting instructions on the pocket, and have a shifter lever on the floor that controls the transfer case.....

 

[Poser]

I don't have the three speed anymore, I am running a 350 into an sm420 into the stock three speed t-case. The PO switched from the vacuum actuated t-case to floor shift. If i am looking at the diagram right, i need to put in another stick to switch the front drive shaft on and off. I am going to go check it out tomorrow because my 40 is not at my place its at a friends (i live in an apt)

You should not need another shift lever, as many people have modified the single shifting stick to work with the 420 and OEM transfer case.

Get under the truck, look at things, even better, take some pictures and post them up out here so we all are on the same page.

 

[rsc71]

I don't have the three speed anymore, I am running a 350 into an sm420 into the stock three speed t-case. The PO switched from the vacuum actuated t-case to floor shift. If i am looking at the diagram right, i need to put in another stick to switch the front drive shaft on and off. I am going to go check it out tomorrow because my 40 is not at my place its at a friends (i live in an apt)

was refering to the t/c shifter.