2009 Tacoma 4WD not engaging

The front differential actuator is new the transfer case actuator is new 4WD will not engage the ADD has been changed 2 times transfer case actuator is new and so is ADD the 4WD light in instrument cluster flashes green when switch is in 2wd or 4hi when switch is in 4L it beeps constantly but never engages

 

I agree.

Seriously man. Diagnose it. Don’t guess.
That gets expensive, as you’ve found out.

Look here if you want to diagnose it and fix it.
https://www.tacomaworld.com/threads/4wd-system-operation-help-thread.742420/

 

Yes I have the first time the ADD was replaced it fixed my problem for about 6 months then came back same problem so I changed the ADD again then 4WD 4L was flashing but no beeping according to threads here transfer case actuator was bad so I bought a new one and installed it same original problem 4WD light flashes but will not engage

 

Sometimes it is cheaper to take it to a professional.

 

Me and my FUCKING driveshaft agree.

 

Like my dad always told me, “You can fuck it up just as good as a professional.”
Let me tell you, I did too.
Not even a professional could fix it after I got done with it.

 

Check your voltage readings and report back. Two issues I see here that haven’t been mentioned:

what brand actuator did you replace it with?

Have you checked operation of the 4wd and 4LO detent switches?

 

On going vibes, for three years, I just can't get rid of them, I can change what speed they are most noticeable by swapping out axle angle shims and carrier bearing shims but nothing I have done has rectified the issue.

I've tried effectively everything I can think of or that has been read about or suggested to me and I have enough hours hand written notes and scars to consider myself just done with it.

What's the actual issue?

Not a clue, best I can tell I haven't lost a weight or dinged it at all, the carrier was replaced with OEM two years ago and made more solid with the urethane injection mod the U joints are all tight and it's in phase, replacing the carrier helped get it tolerable for a while but last 6 months I've be riding the paint shaker instead of just the washing machine.

I can't take it anymore, it drives me crazy I can't relax on my hour commute because I feel like a 5 year old is kicking my seat the whole way.

As much as I want to find out what's actually wrong with the cursed thing I probably never will as I have an appointment in two weeks to see a professional drive shaft shop and will just have them build me a new one. I want nothing to do with my old shaft anymore.

Hoping to get them to build me 4" shaft with a beefier carrier bearing and a double cardan after the carrier, longer slip yoke for my lift and possibly with a double drilled end flange so I can bolt up a 2nd gen Tundra axle one day.

I've tried to become a driveshaft specialist and seeing a real one feels like defeat to me as "I can do anything on my truck myself" but this time the truck won.

I give up and I'm tired of fighting it.



The shaft is fucked that's all I know.

 

You considered going with a 1 piece?

 

Can't, being a manual transmission which is shorter my shaft is too long (not a regular problem for me ) for a 1 piece to work plus for what I (like to pretend I) do I'd rather go 2 piece with the double cardan for rock clearance and the concern of vibes coming back with a vengeance after a regear due to the critical rotation speed scares me; I'd rather not risk it.

 

It’s all good, a specialist will help you out. Chill and enjoy the ride.

 

This and this and this.

 

Up to this point just what I have seen on UTube and threads here this is the first time I have seen anything on the 4WD ECU unit and have not had a schematic for the wiring I did check all the plugs and cleaned them I am about to check the timing on the transfer case switches now I took the switch out of the dash and did not see any apparent problems it about has to be that the fuses are all good

 

Welcome to TW, Mark. I’ve read through this thread and I’d just like to suggest a couple of things.

1. Answer all of the questions asked of you. Some of them are really important, a lot of folks have very useful things to tell you depending upon your response, but they’re probably not going to keep asking if you don’t respond. (see post #10 in particular)
2. Go read at least the first part of the link provided in post #3. It is likely the best diagnostic resource on the interwebs for this specific issue, and if you make proper use of it and then come back to ask questions, you’ll probably get the issue resolved pretty quickly.

Good luck, here’s hoping this gets resolved in short order!

 

Ok guys the issue was in the timing position of the transfer case actuator to time this unit with it installed on the transfer case remove the three bolts and remove the plastic housing “photo 2” remove the gear assembly and put it back in the plastic housing and Reconnect main connection with the wires connected but unit is just hanging, switch is in 2WD high turn ignition to accessories and actuator will come on briefly turn off ignition and reinstall on transfer case this fixed my problem.light went out and stay off came back on and stayed on 4WD and turned off when. I switched back to 2WD high the small gear under the cove on side goes on last. this is combined knowledge of you guys and YouTube videos the photos are in order 1-5 as I was writing this article good luck and thanks for your help