96 pajero auto no power front right wheel i 4wd trans fluid level ok

First make sure that the fluid level is correct. Next make sure that the shifter lever is moving the shifting cable and lever at the transmission, If both of these conditions are ok then you have internal transmission problems.

Hi Jim,
this is rather common. The front axle diff will have a hard time disengaging if the gears are under load. You need a load change (get of the acc pedal, move steering a bit left right, briefly go to neutral on the auto transmission, then back to drive). This will help to get the front diff loose again. Sometimes it really takes some time to disengage! Mostly the problem is gone when you stop the car, switch off engine, release brake, then start again and drive - and voila- back to 2WD. On hard surfaces the transmission can go into a wind-up state (because of different wheel speed when cornering), esp the center diff (4WD and center diff locked) then is under such load that the car virtually stops driving or you can hear crackling noises and tyre slip on tarmac!
Regards, Winfried

try checking the cv ("U") joints for the front drive

i'd advise taking to a autobox repair shop as sounds like an internal problem , only thing that can be done at home is to check the fluid level . follow link for more info
Checking auto transmission fluid level JeepForum com

IF you are in constant 4wd then you will not have a centre diff unless you have an AWD. The difference is that AWD transfer cases have a centre diff that allows different road speeds between the front and rear diffs as in going over speed bumps and dips ion the road It is the same operation in the front and rear diffs that allow one wheel to go faster than the other when cornering. However in 4wd drive there is no diff action in the transfer case and both front and rear axles drive at the same speed regardless of speed bumps and dips in the road . This action produces what is known as torque wind up which results in the handling characteristics. This torque wind up places stress on all the drive line train and results in failures such as .that you describe.. This wind up is not noticeable when driving on loose surfaces slippery surfaces or in mud as it is allowed to escape when the wheels spin . If you have an AWD with diff lock capabilities then check that the diff lock is operating correctly

IF you have both front wheels in the air then either wheel will spin freely unless you have diff lock or limited slip diff. That is the nature of a diff..wd means that all 4 wheels drive but only when you have a limited slip diff or a diff locker. in action . If you have both of one side wheels in a bog you will not go any where.

The front and rear diffs should have drain plugs on the lowest part of the 'pumpkins'. Some vehicles don't have drain plugs tho and you have to remove the big cover to drain. There will be a plug about halfway up each diff to refill usually. The front axle should take SAE 75W-90 oil and the rear takes as follows:

Ambient temperature usually above 50°F (10°C)-SAE 140W
Ambient temperature usually below 50°F (10°C)-SAE 80W or SAE 80W/90 Ambient temperature usually between 0° and 90°F (-18° to 32°C)-SAE 90 or SAE 80W-90 These are all GL-5 hypoid oils.

The fluid for the transmission is not the same as the axles. It is DEXTRON III. Your model is a bit different as a 1996 auto trans must be checked under the vehicle for fluid level as it doesn't have a dipstick. You check the level thru the overfill screw on the transmission pan. Fluid should just seep out a bit when removing this plug.

Check tire size and add a Limited Slip additive in the transfer case!

Howdy, My name is Mark, I am a mechanic (Auto trans and Diff specialist 23 years) this symptom is common with a broken driveline component, with full time 4WD and centre diff all the drive goes to the wheel with least resistance, (or to broken component) therefore when you engage difflock (Center) the drive then goes 2 ways front and rear so vehicle will drive, could be as simple as stripped spline in front wheel hub, broken CV joint etc. 1 major weakness these vehicles have is if driven with center diff lock engaged on high traction surfaces they do break the front diff, this will give the same symptom but you would of been aware of it when it happened.
To check where the drive is going chock all 4 wheels, park brake on, bonnet up, start engine let it idle down (after cold start), engage reverse (high range open center) from the front of vehicle and off to one side you can see the front axles, if one of them is turning that is where your drive is going, have someone to help you and under no circumstances place your self under or in driving path of vehicle.
Hope this helps

The button is to lock the central diff to distribute the power 50/50 front to rear when in slippery conditions,
Normally with button off the drive system favours the front wheels.