4wd wont engage any help will be appreciated

[Raymond05rodeo]

2005 holden rodeo ra 3.6 ltr petrol 5spd man Tried replacing the actuator n buttons on the dash an reseting the 4wd tried rocking back n forward tried both sotf and standing still for 4l neither 4h or 4l will engage ive only just brought the rodeo n not familuar with set ups help will be appreciated

[geeves]

I would of started with the basics. SOTF on your model is controlled by a computer. When you activate 4 anything the computer operates a switch in the transfer case to engage the gear then a second switch tells the computer this has happened At this point the 4wd light should flash. The computer then activates a solinoid on the front diff which locks the diff freewheel and a second switch tells the computer this has activated and the 4wd light goes steady. Most common failure is the vaccum to this diff solinoid. I dont know if a tech2 etc will diagnose the computer.
First test I would try is to see if the front driveshaft will turn by hand in 2wd and with 4wd turned on. It should turn in 2wd but not 4wd. Then lift the front left wheel and see if this is locked in 4wd. Tell us the results and we will advise from there

[geeves]

Also Ive deleted your double post

[Raymond05rodeo]

Thanks geeves ill check it out on thursday tomorrow n ill get back to you hoping to take the kids 4wdriving on the weekend as well so fingers crossed

[qayum1616]

geeves wrote:I would of started with the basics. SOTF on your model is controlled by a computer. When you activate 4 anything the computer operates a switch in the transfer case to engage the gear then a second switch tells the computer this has happened At this point the 4wd light should flash. The computer then activates a solinoid on the front diff which locks the diff freewheel and a second switch tells the computer this has activated and the 4wd light goes steady. Most common failure is the vaccum to this diff solinoid. I dont know if a tech2 etc will diagnose the computer.
First test I would try is to see if the front driveshaft will turn by hand in 2wd and with 4wd turned on. It should turn in 2wd but not 4wd. Then lift the front left wheel and see if this is locked in 4wd. Tell us the results and we will advise from there

Hello there!
Since I'm having the same problem, can you help me too? I already tried to turn the front driveshaft by my hand in 2wd and with 4wd mode, it turned in 2wd but not in 4wd like you said but when I tried to spin the front left tyre in 4wd, it seems that it does not in 4wd (free spinning).

Thanks.

[geeves]

either diff or hub drive flange. try turning the cv shaft by hand with wheel on the ground It should not turn Try wheel up it should turn the wheel. Also if you turn the driveshaft by hand with wheels on the ground does either cv shaft turn

[qayum1616]

I tried to turn the cv shaft by my hand (both 4wd and 2wd mode), like you said it didn't turn when both wheels on the ground and when the wheels are off the ground, i did turned the wheel but there is some resistance at right wheels but it still spinable. I also tried to turn the front driveshaft with wheels on the ground, only the right wheel cv shaft turn a bit.

[geeves]

If it turned 1/10 turn then stoped that is normal. If it kept turning then the cv or drive plate is at fault
My money is on the dog clutch in the front axle. This is vacum operated and 9/10 faults are with the vacum supply

[qayum1616]

Is this vacuum pump? Its making weird noise when the engine is started and do you think this is the problem or there is some leak between the vacuum pipe?

[qayum1616]

https://flic.kr/p/248Wb6A