4x4 actuator or transfer case clutches

[ziggy1969]

2001 Chev Silverado with 4x4 electronic dash switch (build codes NP8/W30) - piled up the front differential really bad. We replaced the front diff from an autowrecker used and appears to be working OK... well almost, hence the question today

Symptoms are, when the 4x4 is set to 4Hi the front diff is spinning front tires on ice only. When in deep snow, the front tires do NOT spin.


Testing:

I jacked up the front right tire ONLY, and did the following tests

- 4x4 set to 2Hi, the tire spins freely by hand

- 4x4 set to 4Hi, the tire does NOT rotate freely and seems to be engaged now, but can still rotate very slowly by hand, however with great resistance. Remember, the other 3 tires are firmly on the ground. I would have expected to NOT be able to rotate the tire whatsover


Was told this is a result of faulty clutches slipping in the transfer case (as this is equipped with 4WD Auto)
Another guy tells me the actuator is not fully engaging

one is cheaper to fix than the other, any suggestions ?

is it the faulty actuator or faulty transfer case ?

[j cAT]

Originally Posted by ziggy1969

2001 Chev Silverado with 4x4 electronic dash switch (build codes NP8/W30) - piled up the front differential really bad. We replaced the front diff from an autowrecker used and appears to be working OK... well almost, hence the question today

Symptoms are, when the 4x4 is set to 4Hi the front diff is spinning front tires on ice only. When in deep snow, the front tires do NOT spin.


Testing:

I jacked up the front right tire ONLY, and did the following tests

- 4x4 set to 2Hi, the tire spins freely by hand

- 4x4 set to 4Hi, the tire does NOT rotate freely and seems to be engaged now, but can still rotate very slowly by hand, however with great resistance. Remember, the other 3 tires are firmly on the ground. I would have expected to NOT be able to rotate the tire whatsover


Was told this is a result of faulty clutches slipping in the transfer case (as this is equipped with 4WD Auto)
Another guy tells me the actuator is not fully engaging

one is cheaper to fix than the other, any suggestions ?

is it the faulty actuator or faulty transfer case ?

you say in 4x4 hi the right front wheel you can rotate by hand ???? that would mean the transfer case needs work. when the vehicle is operated on dry pavement in 4X4 this wears out the clutches. when the fluid is checked and its very dark/black this is the clutch material. actuator does not have a gradual type of engagement its in or out. auto 4WD is 2WD unless the speed sensors are showing different speeds then its in locked 4wd ... then it will auto back to 2WD. in auto 4WD the front axle actuator is engaged. the encoder is NOT until a slip is reported. encoder connects the front to rear axles the encoder creates / engages 4 wd... normally in auto 4WD the front axles should be not connected together ..when it 4wd on solid pavement you should feel the vehicle hop when turning hard at slow speed less than 2 MPH ..

if the encoder/actuators are bad you will get service 4WD error.

[ziggy1969]

Correct

With 3 tires firmly on the ground, ignition on, but vehicle engine not running, set the electronic dash switch to 4Hi (not auto 4Hi) , I can rotate the jacked up front tire. It is extremely RESISTANT, but can rotate very slowly with great effort.

[j cAT]

Originally Posted by ziggy1969

Correct

With 3 tires firmly on the ground, ignition on, but vehicle engine not running, set the electronic dash switch to 4Hi (not auto 4Hi) , I can rotate the jacked up front tire. It is extremely RESISTANT, but can rotate very slowly with great effort.

so it appears that the clutch is slipping... now if the transfer case fluid is black not blue then the clutches are worn. transfer case fluid is blue.. the more its black the more the clutch needs replacing.

[j cAT]

Originally Posted by ziggy1969

Correct

With 3 tires firmly on the ground, ignition on, but vehicle engine not running, set the electronic dash switch to 4Hi (not auto 4Hi) , I can rotate the jacked up front tire. It is extremely RESISTANT, but can rotate very slowly with great effort.

so it appears that the clutch is slipping... now if the transfer case fluid is black not blue then the clutches are worn. transfer case fluid is blue.. the more its black the more the clutch needs replacing.

I just did the tire rotations on my truck and when this is done the vehicle is in 4WD .. then I can lift up the rear axles and remove both tires and the wheels will not spin. then lift the right or left with another jack to install in the front .. all wheels are locked as one . park brakes on front wheels locked .there will be some slippage because its a clutch but for you to do it by hand not really ..

post back how you made out ..