So I was trying to go up a hill today... Just a grassy hill I wasn't even mudding and just tried to go into 4-Lo with the rear diff locker on and the front wheels just wouldn't turn... I'm not sure what happened we tried it several times and nothing... Only two wheel drive... Am I doing it wrong is there a different procedure I should do putting it into four wheel drive? All I did was just put the truck in neutral, shift the four wheel drive to 4lo and the pull first gear the whole way... I could feel the gears grinding a little when I was putting it in to four wheel drive so I know it was going somewhere I just don't know what to do... Any reply will help thanks

 

Does your taco 99 taco have manual hubs and did you forget to lock them?
Saw it happen before

 

not that I know of.. I'll take off the center caps tommorrow just to double check... I hope that's the problem

 

If it has center caps you don`t have manual hubs.

How often do you shift the transfer case into 4 wd??I shift mine every couple of weeks

The ADD actuator the VSV`s can all get stuck vacuum lines can start leaking better to know before you really need to use it.

electrical things can corrode wires can get damaged.

 

would installing manual hubs fix that?

 

and I know it's not electrical due to the locker engaging... The computer knows it's in 4x4 so it must just be the vacuum lines or hubs.. I just looked up a manual hub conversion and it's gonna be a butt load of money so I guess that leaves me with repairing the vacuum lines

 

No, it would only change what is happening at the wheel, not the diff.

 

okay what do you think I should do

 

Just because the locker is engaging or the rear is working doesn't mean the front isn't having issues. As Wyoming9 said there's electrical and vacuum components. If you're sure the front isn't engaging start there.

I am assuming you don't have two busted cvs (and that you have cvs) and that the front driveshaft's intact. I don't know what the truck's history is or what any po might have done to it.

 

Not trying to be critical of you, but on my 01 Runner, there is a 4WD button on the transfer case shifter. Did you engage it? I knew a guy that was not happy with how his 00 Runner was acting. He was dis engaging the Over Drive thinking that activated the 4 wheel. Also I dont know the Tacomas if they are set up the same as Runners.

 

nope not any buttons on mine fully mechanical tranny and transfer case thanks for the idea though

 

me and my brother will try to trace all electrical stuff this weekend thanks

 

You never said if this is auto or manual??

Two very different systems !!

Then I sure would not want to look at the electrical end of this without the schematics your just going to get frustrated .

Now unless yours is wired different then my 2000 Just because the rear differential is locked does not mean that the ADD is engaged.

Then your truck could have some custom wiring additions.

One never knows the interesting things one might find.

 

okay what should I start with the ADD?

 

Have you checked the fluid level in the tranny, tcase, and front diff? Is there fluid. How does it look how does smell?