KyleStubbins.com

try the 4x4 actuator on the fire wall

I have a problem with my 4 wheel drive whenever I push the 3 buttons on my dash I can clearly hear the TCCM click and hear movement in the transfer case
When i push 4 high it lights up and shaft to wheels engage
when i push 4 low the 4 high button lights up and the 4 low flashes on and off also the shaft to wheels engage but no 4 wheel drive
can you help me please? thanks in advance

Great blog Kyle, the front wheels on my 01 Blazer are not pulling. Stuck in the snow today, only the left rear wheel spun.... the dash lights show that all is supposed to be working lights do change from 2W, 4WH & 4WL fine and normal, the relay clicks in the door pannel and I can hear the shift motor run and hear it move shift lever in the T-Case but no front wheel power....where do I start ?

Would a battery disconnect help with all lights working normal ?

Could it be vaccum ?
or
corroded terminal in door panel ? (Again, electronics seem to be working)

Thanks,
Bob (Ohio burried in 2' of snow)

Kyle's reply;

Hi Bob;

Unfortunately, the only thing that I can thing of at this stage is to get the vehicle off of the ground and see if the front drive shaft turns when the dash lights show you're in 4WD. If doesn't turn, the problem should be in the transfer case. If it does turn, the problem should be in the front differential. Basically, where ever the motion stops is where your problem lies.

Good Luck!

Kyle

Howdy Kyle,

I dug in to the problem, got all four wheels off the ground and no power to the front wheels. I checked the module behind the kick panel, everything was fine there it looked like new. I checked all fuses and everything OK. So now I pulled out the battery and battery tray and checked the cable to the vaccum assist pot, the cable was free but the pot was not pulling shut. Then checked the 3 vaccum lines . (1) vaccum line to the right side of the manifold , all was OK. (2) Bleed-off line from transfer case to vent cap attached to the transmission fill tube, OK. (3) vaccum line from the transfer case to the vaccum assist pot, no vaccum .... Pulled the molded 3-line vaccum plug from the transfer case and had vaccum on one line so I rotated and reatttached the plug to the transfercase and the vaccum pot pulled shut and engaged the front differential but would not disengage when put back in 2WH. Soo I rotated the plug one more position and all worked fine. (It does take a little while for the vaccum pot to bleed off) Someone had taken the vaccum plug off the transfercase and put it back in the wrong position. So when everything shows working on the dash, check the vaccum at the transfer case plug. 4X4 now working great !
Bob

Kyle,

I've replaced the front wheel hub assemblies twice and now the front right is howling again... seems like 30,000 is all I can muster out of these bearings. Any suggestions on better replacement bearings (Used Timken last time) or reason for this quick wear-out ?

Thanks,
Bob