# 87 D21 - 4x4 will not engage



## BBDirtbiking (Mar 6, 2009)

Alright, I have a 1987 Nissan D21 4x4, 3.0L v6, and just recently I went mudding and soon realized my front tires would not engage into 4 wheel drive. I made sure the hubs were locked and made sure i was in either 4H or 4L, but the wheels still wouldn't turn. The gears changed to low and everything but just the tires weren't spinning. If anyone has had this problem and know what it is please get back to me in this thread...or if you have any clue to what it could be, please also respond.


There is so much rainfall right now and I have no RIG! It's murder.


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## dvdswanson (Nov 6, 2005)

someone didnt steal your frt driveshaft did they?

jack up the frt end. lock both hubs and spin the wheels by hand. 1st check to see if the halfshafts are turning (on both sides) then check to see if the frt driveline is turning. if they are then your prob is in the t/case. if the d/line doesnt turn its in the diff and if the one or both of the halfshaft dont turn its the hubs.


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## BBDirtbiking (Mar 6, 2009)

Thanks for the advise dvdswanson, i will try that as soon as my friend is able to assist with a jack strong enough to lift my fat a**. Hopefully tomorrow, as there is so much mud right now. Also, if it is a prob in the transfer case or differential, how much am i looking at too fix it... i am running low on money lol.

Also, if one of the hubs are bad, does it make it so the 4x4 wont work period? because the person who owned my truck replaced only one of the hubs (dont they come in pairs) so that may be the problem, but at least one front tire should have spun...


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## Hardbodyblue86 (Jan 9, 2009)

If it is a bad hub it makes perfect sense that neither of your front tires are spinning. The differential in these nissans (unless it's limited slip of course) will transfer power to the wheel with the least resistance - which is why on snow/ice when you spin one tire in the front or back then that spinning tire becomes the ONLY moving tire. 

I had a WARN hub shear the studs, pull the snap ring, and fall off my spindle - and in four wheel drive it just spun in the wheel bearing and I had no 4wd because my differential only gave power to the hub with no resistance.

Not sure why it's that way.... but it's definately a culprit.


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## BBDirtbiking (Mar 6, 2009)

I am hopping that you are right hardbodyblue86. That makes the most sense because i would have heard something more serious probably. Just cannot wait to show my Jeep friend what my Nissan is made of, even though he has posi in the back a locker in the front...i was going most everywhere he went when i was in 2wd (i think he was not going to rough because he knew my 4wd wasnt working)


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## BBDirtbiking (Mar 6, 2009)

Alright, just if anyone is wondering, it was the hub. What i did to repair it, because i had no money, was to take it off and look at it...as simple as that....Almost. After getting it out and locking/unlocking it i found that the gear that is supposed to move up and down wasn't moving up and down...So i took apart the hub even further and discovered that the two notches that are used to raise and lower the gear were very small and were in fact missing the spring completely causing everything but the gear to move up and down preventing the hubs to lock. I then took the innermost ring that has the two notches on it and took a chisel and hammer to the notches popping them out more to have more of a structure to them to catch on the spring they turn around. After doing that and then attaching the Hub back onto my truck, i soon found out.....MY 4x4 WORKS!!! So if anyone else is having this problem, here is a easy and inexpensive way to fix a stock Nissan hub, total time was probably only 20 minutes, which in that time i also tightened my alternator belt and air conditioning belt, as they were acting up.


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