Hi,

2009 Tahoe,

Tried to use my 4 wheel drive in the recent snow storm and no dice, got the "Service 4 Wheel Drive" message. Brought it in for service and mechanic says actuators were stuck, he cleaned them up, but did not say I should replace them unless it happens again. Worked fine for a few ski trips and now it is happening again. My question is simple, he says I need "new 4x4 actuators". I thought there was only one, on the front, am I incorrect? Is there one on the transfer case? Also, I see a number of options for replacement, any suggestions besides the $190 the dealer wants to charge me for one? I am going to do it on my own, did not realize how easy it is to replace.

Thanks,
Joe

 

theres only one actuator on the front axle and a motor on the tcase and personally I don't recommend anything but OEM if its an electrical component, there are places out there that offer OEM parts at lower prices.

 

I too am a proponent of using genuine OEM parts, but there are numerous aftermarket products which work well.

Lots of times, failure to transfer into 4lo or hi is due to non use. You should have reasonably fresh Fluid in the case, and transfer into 4W (both) at least once a month. This keeps the slides clean though maybe a little slow to change.

There's a "coasting" procedure to assist a change, and, when one does make a contrary case shift, they often only do it once. When selecting to "exercise" the transfer, one should do it several times, just to make sure everything is operating well.

PS, "exercise"...
The process of changing from standard 2WD, to 4WD-hi, to 4WD-lo, then back in that order, several times. You should also drive your ride a reasonable distance (a mile or so) in each before changing to the next.
I know this is a PITA, but it does keep things stirred up and working.

 

Thanks!

What is the "coasting" procedure? I used a coasting procedure with the old transfer case shifter and locking hubs, did not know there was one for the electrical systems.

 

Basically the same thing, usually used for "coaxing" little used/sluggish 4
wd's to shift.

Get going a little over 5 mph,
Shift into 4hi,
Shift into Neutral, and let your speed drop below 5mph,
Shift into 4lo.

The transfer into 4lo may take a few seconds,
If it returns to 4hi then,
Put it back in gear, and increase speed to just above 5mph,
Then put it in Neutral, and as it drops below 5mph
Shift into 4lo again.

On a very contrary Case, you may have to do this several
times to make it shift into 4lo.

Once you get it to change, see my previous post about "exercising".

 

Thanks!