m211 intermediate duals trouble

[WAYNE_L]

didnt notice till snow got deeper that my front axle is only getting power going foward and nothing from my middle axle drive shaft spinning but, no power ..

so i pulled axle shafts ,seeing its easiest to do first both were in good shape ..So only thing i can think of is broken ring gear or pinion .. no crunching or catching in the diffs i hear .. i just drove it 40 miles with no problems at all till i backed it into my drive ..


im guessing the tcase is out of adjustment for reverse front axle not engaged ..but i wouldnt think a diff this big would be broken ...

any ideas ?

 

[Baradium]

I'm almost afraid to know what is up with that axle Wayne. Doesn't seem like anyone here has any ideas either.

We have our work cut out for us when it warms up.

 

[rosco]

Let's see - its been years..... So what happened when you backed into the drive? What was happening, or not happening? Before you pulled those axles, you should have just pulled the fill plug and stuck your finger in there, got lube on it, and looked to see if you have metal filings on it. I doubt that is the case. But most probably in your T-case.

You say front axle - be specific.. Steering axle? Is it working? Is it pulling? The gearing in the T-case for the steering axle is slightly faster, then it is for the rear drivers, so that it only powers the steering, through two sets of sprague clutches - one forward, one reverse. When the rear drivers start slipping, the the rear drivers catch up with the front, through the spragues, and they enguage the steering, and power it. The linkage for the sprague clutches must adjusted properly, or there can be no power output.

Power output to each rear driver is mechanical. If you think one or the other rear driver spins the driver line, but doesn't get power, then jack the wheels up on one side of the rear end, and try to spin them by hand. If you can, and the drive line spins, its the T-case output.

 

[rosco]

Wow, now I see that we're all ihere, n the far north. Those are real good trucks. They just need their share of TLC!

 

[Baradium]

Hey Rosco,

We have two seperate problems.

First is the forward tandem. The driveshaft spins but the tires don't get power. So the driveshaft will be turning with neither wheel spinning. That eliminates the t-case as the problem. Since both axle shafts are good, it seems that it has to be something in the differential itself, we just don't know what. Again, the driveshaft only spins when the transfercase is trying to turn it.


Second is that the front axle doesn't auto engage in reverse like it should. We think it's an adjustment issue is all. It gets power in forward, just not reverse. With the forward tandem not working its traction abilities leave much to be desired.


This is a problem from when we first picked up the truck, so it's likely not something that happened while we were there. Although when we went to pick up the truck the guy had left the line lock on for the brakes and was trying to move it with the brakes locked down.

If I pull the axle shafts on the forward tandem just clear of the studs, I can feel them engaged to the carrier, and they will spin eachother (opposite directions) as well as spin still with one being held.


I guess I should also clarify, I'm half owner of that M211 with Wayne above. He hasn't gotten to drive it much at all this winter between it being a one wheel wonder and me breaking off a fitting inside the air horn solenoid when I pulled the horn to clean it out (it was clogged up). Dumping all the air out does wonders for your brakes.


This truck also has a military conversion (it was refit in 1962) that gave it a manual valve body for the transmission. I haven't ever looked at another M211 up close, is that a common retrofit?