Four wheel drive will not engage

spyac3 · 2007-12-04T14:54:18+00:00

V6 four wheel drive automatic 105,000 miles. Hello, My truck has an automatic transmission with a turn knob switch for engaging the four wheel drive. When I switch from two wheel drive to four wheel drive high or four wheel drive lo the lights on the dash come on but front wheels never engage. I have checked all the fuses, and removed the electronic shift motor from the transfer case the motor appeared to work fine. Since the switch activated the shift motor I would guess that it is not the GEM, fuses or relays. Since this system is a "Vacuum Pulse" system is there a vacuum line somewhere that could be faulty or a o-ring that is faulty, I do not fully understand how this system works I see a lot of posts for this problem but no answers other than what I have checked. Any help is appreciated. Thanks

1999 FORD RANGER

STEVENBCU

MEMBER
4 POSTS

i don't mean to sound stupid, but this is going to sound stupid.
drain oil from where? oil pan? transfer case? I am kind of confused on your suggestion.
Sorry

thanks for your help

Jan 13, 2020 at 7:37 PM (Merged)

MERLIN2021

CAR REPAIR CONTRIBUTOR
17,250 POSTS

drain some of the oil from the front axle at the fill plug!

Jan 13, 2020 at 7:37 PM (Merged)

MIKE H R

CAR REPAIR CONTRIBUTOR
3,094 POSTS

in the somewhere in the middle of the front axle there is what looks like a plug with a square hole, this can be taken out with a 1/2 inch racket, once you get the plug out get a smple of the fluid, don't need to much, put it between your fingers and rub them together if it feel gritty or you see metal filings then it could be the pumpkin like merlin 2021 mentioned

Jan 13, 2020 at 7:37 PM (Merged)

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