2004 Limited

I just swapped my front diff with a complete 4.88 clamshell from ECGS to match the rear. Everything went smooth. I start testing 4wd by putting in 4hi and I get nothing. The light is solid, the front driveshaft spins but there's is no power to front wheels. When I give it gas the runner doesn't move nor does the rear driveshaft spins. Front driveshaft spins whether in N/D/R but no power to wheels.

I try 4l, same thing. I then put it back in 4hi and lock center diff and both 4h and 4l work. I don't think the front diff is actually engaged though, it's just the center diff locking driveshafts together that is pushing the truck.

Vacuum hoses are on and look good
ADD electrical connector is clean and looks good.
I can hear the front diff/ADD grumbling when switching to 4wd.

Any thought?

Thank You

If the front drive shaft is spinning when in gear then there something in the front diff not transferring the drive shaft input to the axles.

It, I think would have to be an issue with the install or the new clam shell, have you contacted ECGS for their advice?

Forgetting to install the front CV axles would have the same symptoms as you describe. I'm not saying that's what it is but sounds like something isn't transferring power to the front wheels somewhere after the front driveshaft.

My brother forgot to install a stub shaft into the front diff of his FJ when he did his swap. I don't remember his symptoms but I didn't have to do it on mine because mine doesn't have ADD. I think you remove it from your old diff and install in the new.

Type this into your searchbar and you should be able to find a PDF from ECGS:

'05+ Tacoma, 4Runner, and FJ Cruiser Front Differential Removal Instructions'

The very last paragraph they call it a stub shaft.

I think it looks like this, I don't remember though:

[SOLD!] Front Differential ADD Gear Stub | Tacoma World

This was it. Thanks a lot man. The new clamshell even had a sticker on the passenger side that said don't forget the stub shaft. I just looked at the old one and could see it still sitting in there and just popped it out. Lol I thought it was part of the tube assembly. Smh...

Question now is do I have to drop the who'll diff again or can I just remove passenger support and tube?