4x4 not working

[KMSCD]

I will start my first post with a fun one maybe

I have 1989 w250 and the 4x4 is not working 4hi or low I get nothing



thanks for the help

 

[Philip]

Stick shift or auto?



It could be many things. Broken transfer case input shaft. Striped out spline connector between the trans and transfer case. Broken out put shaft on the trans. Gear reduction box on the transfer case blown.



Do you hear any noises when trying to move?



Welcome to the TDR

 

[DavidBurt]

Don't forget a locking hub broken if it has them.

Dave

 

[ClarkP]

This might sound like starting with the simple logic, the hubs are locked in or are locking correctly? Second, on my '92 there is a sweet spot you have to hit other wise nothing, you will stay in 2WD or if in 4WD if you don't hit it right on the way back you will stay in 4WD. Does the 4WD light turn on when you shift into 4?

 

[BHiggins]

I agree with DavidBurt, start by checking the locking hub. If one isn't locking, your four wheel drive won't work. Lock one hub at a time, and see if you can spin the axle by hand (you can reach the axle by the steering knuckle, you'll be able to see the u-joint). If the axle spins with the hub locked, then the hub is shot.

 

[KMSCD]

I was leaning towards the hubs locking cause there is no noise and power seems to go down when I pull the stick to 4hi postion ( could be all in my head) and the light I cant tell if it is coming on or not



are the auto hubs a a easy fix

 

[AKimmel]

If your truck is a gas truck with a dana 44 frontend, then its your vacuum switch on the top of the transfer case. They stick and won't lock the axle in or out dependeing when it stuck, and the light will either be stuck on or off.

 

[KMSCD]

well got the it fixed its a a very small rock in the hub making me thing it was truned all the way when it was not



thank for the help

 

[91W350]

I know you already have it fixed and we are all glad it was free.



In the future though, unlock the hubs and put the t-case in neutral and check for free rotation of the front driveshaft. It should turn very easily. Now lock in the hubs and turn the front driveshaft, it should turn about 1/4 turn, if your front axle has badly worn parts, I have seen over 1/2 revolution of the driveshaft. Normally it is a combination of worn kuckles, axle and spider gears and ring and pinion slack. Sometimes I will jack up one wheel and turn the shaft, you will be able to feel broken gears quickly. If it turns about 1/2 turn and stops with a wheel in the air, you may have a locking differential, jack up both wheels and check for free rotation. You can also unlock one wheel and check each side that way for free roatation. For front axle use, the Dana 60 is a very strong unit and seldom causes any problems.



If all seem well with the front axle, unlock the hubs and put the T-case in 4wd. Now the front driveshaft should only turn less than 1/8th revolution. I am sure you see the logic, just eliminate the probable problems quickly. I have removed the rear driveshaft and put a few miles on the truck with just the front axle pulling. That will quickly tell you if all is well.



If you do not know the history of your truck, I would recommend draining the fluids out of the t-case and both axles, checking for water (Looks like milk) and metal shavings (glitter in the lube). A lot of members use synthetic lube in their trucks, I am one of them.



Like the others, welcome to the TDR, glad to have another 1st gen around... .



Glen

 

[KMSCD]

thanks

I am planing on getting it up a lift this weekendand checking things out so I will play with that stuff is there any other week spots I should look over



It a well maintained truck and keep very stock part of the reason I pick I went with this one

 

[91W350]

well maintained truck

That makes all the difference in the world!



If you find something that concerns you, just post a note. The experience and knowledge you have tapped on this forum is better than any manual I ever had in my hands. These guys are amazing. Glen