1998 2.7L manual 5spd 4wd troubleshooting

my 1998 tacoma 2.7L doesn't seem to be functioning properly in 4wd.
when i lock my hubs the driveshaft to the front axle locks, BUT i dont get any pull on the front wheels when driving in 4H or 4L.
when i conducted this test, nothing went wrong.

TEST: lock hubs, jack up one wheel at a time. while jacked up, spin the wheel and the front driveshaft turns. this means that the hub is not broken, right?? did the same thing for both wheels and they both cause the driveshaft to turn. why do I still not have pull on my front wheels when driving in 4H or 4L?
any idea what this means?
I started examining after I got stuck in sand last week. my front wheels were not getting any pull even when driving through my e-brake. something must be wrong but i don't know what it is. help would be much appreciated. thanks

 

Will your transfer case spin your front driveshaft if all 4 wheels are off the ground? If you don't feel comfortable doing this at home, a mechanic might let you try it for $20 first thing in the morning or when they're having a slow day

 

Sounds like a good test. But just to clarify, your saying to support truck with all 4 wheels off ground. Then start truck and with hubs locked in and in 4wd, put truck in gear and verify that front wheels spin.... right?

 

I have only jacked up the front wheels one at a time. Thanks for the suggestion. Can you describe the conditions for that test in detail

 

Very simple test. Engage 4H or 4L. Then jack up one front wheel. Engage both manual hubs. Try to spin one front wheel. You shoul not be able. You should be able to free spin the wheel only in 2H.

Even simpler test. Engage 4H or 4L. Unlock both front hubs. Get under the truck and by hand try to spin front driveshaft by hand. You should not be able to. If you can, your 4WD in transfer case is not engaging so something wrong in transfer case.

 

All wheels on the ground, With tranny in neutral, 4wd engaged, and my hubs unlocked, I can turn the front driveshaft by hand. When I lock the hubs I can not turn the front driveshaft by hand (even when in 2H)

 

When I'm in 4wd withhubs unlocked and all wheels on the ground, I can turn the front driveshaft by hand. This means transfer case is not engaging 4wd?

 

Certainly sounds like something with the transfer case to me.

 

Yep. In very technical terms you transfer case is f***** up or in lame terms 4WD is not engaging and now you are very happy owner of Prerunner

 

My bad forgot manual hubs. Same thing as Rysium's test if you didn't have them. Where are you located? Transfer cases are all over SoCal on Craigslist.

 

Yeah. I forgot about the manual hubs so you don't have to mess with taking the wheels off the ground to find out if the transfer case is bad - it's what I suspected tho. It's probably an easier fix than the front diff though so that's good news.