Four-wheel drive

[heveymetil]

Evening folks....all is well in 4x4 land. The job took the local shop about an hour or so to complete and when I picked my 'hoe up, I got a little education too. Forgive me if I am repeating already-known knowledge...

Turns out, with these GM "push-and-pray" 4-wheel systems, there are two electronic motors in the system: one of these motors engages the transfer case when actuated and another motor, in the front differential, simultaneously engages the front axles to get POWER.

The problem with mine was this front diff actuator - to break it down Crayola style, my transfer case motor was fine and engaging, but the motor that hooks up the axles was dead in the water. Therefore, it "sounded" like everything was good...but the tires were gettin' nothing. Here's the break-down in price: 175.00 for the actuator, 65.00 for labor (one hour) and 21.00 for tax (NYS...gotta love it)

I hope this helps....let me know how everything works out...

HEVEY

 

[bsamoul]

Maybe something is wrong with the actuator. I should get out my volt meter and check out to make sure things are actually getting power.

BTW loulblades, the pin connector has 2 pins.

 

[loulblades]

Maybe something is wrong with the actuator. I should get out my volt meter and check out to make sure things are actually getting power.

BTW loulblades, the pin connector has 2 pins.

A 2 pin actuator would be indicative of the thermal type. A motor type has 5 pins (4 are used).

You can check across the actuator for 12 volts when the key is on and the 4WD switch pressed. You can also remove the actuator and put 12 volts across it and see if it operates. If you remove it, you can put a dowel or something to push on the differential through the actuator hole and see if it is moving freely.

If all seems good, it would then appear that you have a bad sensor (the 2 pin connector above the actuator). Measure from ground to each pin (with it plugged in), when in 4WD you should see 12 volts on each pin. I have not replaced one of those switches so I'm not sure what it would take.

Take a look at the document I posted in the Troubleshooting section because there might be a fault code that will help you.

 

[heveymetil]

Does anyone know if the Front Diff on our earlier Hoe's (mine is a 1998) is a true "locker"? Today I was stuckin in about two feet of snow, trying to get her out in 4 low and 4 high and both front wheels weren't spinning. My friend was outside, saying that the right front was spinning but my left front was totally stationary.

Any insight is appreciated.

Thanks....HEVEY

 

[loulblades]

I know my '96 doesn't have a locker in front but I'm considering putting in an ARB locker when I change out the gears.

 

[blk87brd]

I haven't seen any indication that any of the Tahoes were factory equipped with front end diff locks. At best they are a three wheel drive to my knowledge.

 

[diesel1114]

hey guys its funny my new tahoe a 1997 4dr that i just picke dup kinda does the same thing except it will go into 4hi and not blink but 4 low just blinks and nothing, how can i determine 4 low ? is that control on teh front diff or in transfer case

new tahoe guy
john

 

[loulblades]

The transfer case encoder motor selects 4LO.

 

[diesel1114]

ok so would i feel it move if i tredo tto do that other thing u guys were saying with key on engine off and feel if it moves

 

[loulblades]

You can hear the encoder motor on the transfer case run when you select the different modes. You should also be able to hear the front differential actuator operate also.

Check the 4WD Diagnostics document in the Troubleshooting section that I posted.