Intermittent 4 Wheel Drive

I have an 06 TRD 6 speed. Just picked it up in January. I live in Northern Maine and have been using the 4hi in and around town with no problems. 4lo as well for backing through deep snow. My problem seems to be when I drive for a while in 2hi (really anything more then 30 minutes) and the truck does not want to shift into 4hi. I just get a blinking light. Once the truck sits for a few hours it will shift in and out of 4hi or lo no with no problems. I have read about the front ADD actuators going and assumed it was probably this until tonight. I took an hour road trip using 4 wheel drive the whole way, pulled it out as the roads got better, and when I went into town I needed it again. I tried to put it in 4hi and the light started blinking so I pulled over and banged on the transfer case and actuator under the cab and rolled the truck forward and it went in. It would then easily shift into 4 lo as well.

I tried to repeat this process with the same results, I pulled it back into 2hi and then the only way to get into 4hi or lo was to bang on the transfer case and transfer case motor.

I guess my real question is should I try and flush the fluids in the front end and transfer case? Or should I replace the shift motor on the transfer case? Or should I try and clean my ADD and solder the connections.

 

The contacts in the actuator are know to corrode.
When you bang on it, you are probably jarring it just enough to make a better connection.
Then while driving, it gets jarred back loose.

The actual contact points are just touching.
They aren’t really held together by anything other than friction.
Some people solder the connection. If the corrosion is really bad you may have to replace the actuator and then if you want to, you could solder the connection.
That is if you want to open up a NEW part. And the part is pretty expensive.

Here is a good read on it with pictures.
https://www.tacomaworld.com/threads/how-to-trouble-shoot-4x4-actuator.263525/

 

Thank you so much, I should have plenty of time this week due to being out of school and work due to the virus... Seems like a pretty straight forward fix.