LJ 70 - Transfer case clicking problem...

[kkpanayotov]

Hello to all...
So... i have this 70 series 2.4 TD toyota.. with R151 Transfer case and it has a problem which i cannot find to repair...
When getting lot's of power the t-case just clicks and on the next moment there is no power given to the wheels and at the next there is like hard push on it and power restore to wheels and again ... Something like when you change the gears on Low to Neutral and Hi, but very fast but without the bad noise like trying getting on reverse in 50 km/h...
I opened the case... nothing special nothing worn... I was thinking of the Some of the Clutch sleeve so worn out or the teeth or the gears but everything is fine, there is no problem with them ...not worn at all...
Next i though of the 2wd and the 4wd. The Shift forg shaft has a spring on it and i thought it was broken but no... it is very hard and it is ok...
Can any one give me an reasonable explanation from where might the problem comes?
Thanks...

 

[SimonInAustralia]

Maybe gearbox output shaft has stripped splines, if it has the same 2 piece gearbox output shaft problem as early HZJ78 Troopys with the R151F.

 

[kkpanayotov]

nope... they are all fine...
anything else ?

 

[prado t]

Vacumm engagement? There is a diaphram on your case that engages 4WD.

 

[Cruiser70]

Check your front locking hubs are locking.
The noise you describe sounds like mine when I engage the switch for 4wd wihtout the hubs locked up and driving, which is only by accident
They might just need popping off and cleaning and greasing, provding they are off the manual type?

Martin

 

[kkpanayotov]

First thank you are...
prado t : i have changed the 2wd/4wd vacuum to lever type, it is from my point of view not the problem there...
Cruiser70 - it is not the hubs, i have check them.
It is not only the front axle that looses torque but both rear and front... something like , as i wrote down, the clutch sleeve of neutral and Low/High gears to move out from it's place... but there are absolutely no sighs of problem there...
Please if you think of some problem, write it down.. i will really appreciate it !
Thanks

 

[oldblue]

When it drops out of drive, does the Hi/Low stick move ?

 

[kkpanayotov]

Not at all ... Every lever is not moving at all, but the drive just clicks, stops giving power, and on the next click gives and so ...
Really i can find it and it just blows my mind...

 

[Cruiser70]

check for bent linkage on the h/L shifter, meaning its not quite going into gear.
You have to see if its all in tollerance I guess, sounds a bit odd, it must not be aligned up somewhere, I have the workshop manual if you like ?

And going back to your lever system modification for the H4 swtich, explain please, is it possible this is causing the issue? I would have thought you would still have drive at the rear of the vehicle..
Does it occur when you are in both low and high ?
How are the UJ joints on the prop, cant believe that would be the cause of huge loss of power?

 

[kbushnz]

If you are losing drive to both front and rear at the same time then I can only guess it has something to to with the transfer case is dropping into N so its not fully in H or L.
Or the splines are stripped in that part of the transfer-case.
Or the main drive spline from the gear box into the transfercase is stripped.
There is a coupling between the two boxes.
I would remove the pto cover and get someone to try and drive the truck and see if this is turning.
If it isn't then you know its not in the transfercase.
ToyoDIY.com
Item 36211A

 

[kkpanayotov]

I have checked the splines and they are as perfect as new !
Checked the teeth that connect with the clutch sleeve on Low and Hi Gears - they are also normal...
Anything alse ?