4WD lo will not engage. I have purchased a 2008 Toyota 4Runner Sport recently. 4WD high works fine,

I recently purchased a 2008 Toyota 4Runner Sport. 4WD hi works fine and centre diff lock works fine, but 4WD lo will not engage. Looking for tips.

 

Are you following the proper procedure?

You have to be stopped, and in neutral to engage 4LO.

 

Agree with Thatbassguy. 4LO only engages when the right procedure is followed.

 

Yes I am putting it in neutral with my foot on the brake. Today I checked the 4WD fuse. It is fine. Then I removed the power plug on the actuator. It was perfect with no corrosion.

 

In addition to above, 4hi must be fully engaged before shifting to 4lo.

 

What actually happens when you try to engage 4LO? Does the light flash?

Does your 4runner have the rotary switch on the dash? Or, is it the lever type?

I seem to recall there being a trick to it on my '03.

If there's a specific process, it should be in the owners manual, and might also be printed on the visor.

 

Drive vehicle at 20-30mph.

Lift foot off gas pedal, shift into neutral while coasting. Select 4HI. Shift into drive. Drive until 4HI is engaged.

Pull over and stop the vehicle, shift to neutral, rev the engine slightly and remove foot from brake pedal to eliminate all driveline torque. Place foot on brake pedal. Select 4LO. Wait for light to indicate 4LO is engaged. Shift into drive.

Drive in a straight line at low speed to confirm operation. Stop vehicle, shift to neutral, foot off brake, blip revs, select 4HI, shift to drive, proceed.

 

Toyota (and other) 4wd vehicles like to have the 4-low exercised regularly to keep everything free and clean and the gears lubed. If that's not been done, use what chassis suggests above and keep trying it in slightly different ways numerous times. Hopefully it will free up and engage, and then use it a bit every month.
There was a great post a while back on the Tacoma World forum where a Toyota employee posted a great video of how the 4wd engagement system worked and how it's configured.