I would check all rubber lines for hidden holes and cracks. I had a few before discovering the problems with the switch and actuator. I have a 1993 W250 which probably has a different set-up since the 96 is a design change.

 

thanks, i did find rust had ate a hole through one of the vaccum lines.

 

Hey guys, I couldnt find the number on the actual transfer case, but I did find a number under the hood. Just says: Transfer Case 241

 

I still havent figured this out yet guys, I took the shift motor off the top of the axle, put a new gasket on it, re-installed it, and the 4WD light stopped blinking when I was driving or stopped. Then I needed to use 4wd going out of a driveway, so I have to shift it back into 4wd, the light came on, 4wd came on, got my out of the icy driveway, put the 4wd stick back to 2Hi, then the light continued to blink again like it did before. I tightened the bolts on the shift motor, 4WD light still blinks, it seems to blink faster as I speed up, then it just stays on constant, I push the clutch in and it blinks and stops. Mind you, it does seem to be in two wheel drive now, as the lights blinking. but I dont trust it enough to drive it. Anymore ideas? Im lost on this one.

 

You have a vacuum operated 44-8FD or 44F-BJ Spicer front axle also known as Ramtrac. You also have a New Process 241 transfer case. I am told this transfer case is the only one used with the Spicer axles.
The diaphragm moves a fork that then moves a collar that engages both axles and locks the front end. Have you done a vacuum test on the diaphragm on the shift motor? The reason I ask is this sounds like the coupling/collar is not being held solidly in the 2 wheel position and it is hitting the 4 wheel drive switch turning it off and on. That is usually a vacuum leak problem of some sort.

 

Alright, I'll try testing the vacuum I guess

 

Bit of an update guys. I found that my trucks not actually in 4wd. But I still have a loud clunking noise when I make hard left or right turns. Also, I sometimes hear a grinding/popping noise comeing from the drivetrain, sounds like it might possibly be comeing from the t-case. Its got an NP241 case. makes the noise when it 4wd, but its more of a squeeking/ creaking noise, but gets louder as I move faster. Any ideas? Also, I changed the fluid, it was quite low when I checked it before, I noticed it looks like its leaking up where the driveshaft goes into it, maybe just a seal? Thanks again guys!

 

Have you checked the U-joints on the axles?

 

Not on the axles, but did check the driveshaft ujoints, there good. Im gonna check the axle u-joints tommorow. Do ya think that would cause the metal grinding/ popping noise too?

 

Yes. Especially at hard right and left turns but even straight ahead once they get bad enough.