Dana 18 Not Shifting Back Into 2h

He says the issue started after pulling the plow and it's been a year since the axle swap?

 

that was my inclination as well, but when I asked if the transfer case still got stuck when he shifted into 4wd with the front hubs UNLOCKED, he confirmed that it did still get stuck. Even with wildly mismatched gearing front and rear, it shouldn’t cause anything to get jammed if the hubs are unlocked:

In that case, the spider gears and ring/pinion would still be spinning but they aren’t driving the front wheels due to the hubs being unlocked. So a mismatched gear set wouldn’t cause binding. there must be something wrong with the R&P or spider gears - broken teeth, really bad backlash, etc.

another possibility could be severe front driveshaft misalignment.

 

Sure sounds to me like a problem with front differential. Not turning freely. Don't see what else it could be if it's binding with the hubs unlocked.
Have you tried spinning both front tires in the same direction at the same time when you have it up in the air?

 

I missed it still locking up with the hubs disengaged. Yeah, probably a front axle issue if that's the case. We'll see when the diff covers come off.

 

I'm pulling them today. I'll confirm they are 5.38s in there too.

 

If I had to bet $, spider gears-----

 

Spider gears are perfect yet, everything looks good in the diff. Here is the ring stamp showing 5.38 gearing.

 

Front spiders are fine. No visible carnage

 

Have you tried spinning a wheel by hand with the cover off, so you can watch the full rotation of all the gears?

And you’re 100% sure the rear gearing is also 5.38?

 

I'll check rear next, but yes. I'm 99.99% sure it's 5.38 gearing back there.
If i spin one tire while it's on jacks and I'm watching, the opposite tire don't spin. It wiggles a bit, but won't spin opposite direction of the one I'm manually turning.
Hubs are engaged.

 

I spin the passenger, spider gears spin, drivers tire doesn't move.
I spin the driver side tire the diff gears spin, but not the passenger tire.

Maybe a broken axle shaft?

 

I hate my life.
Just checked the rear axle, I have 4.27 gears in the back! Gear stamped 47-11.
Checked the math...4/11=4.272727.

Also matches the axle ratio tag.
So I rebuilt a front axle to an imaginary gearing I don't have in the back.

 

Anybody want an axle ratio tag? Cheap...

 

Looks like this is getting installed sooner than a winter project

 

That'll do it. At least the problem is solved.

 

Possibly a broken axle or front u-joint, but be methodical in you examination. Put it in 4wd and 1st gear so that the drive shaft can’t turn. Now when you turn a wheel the other should turn in the opposite direction. If the drive shaft is free to turn, you could have the motion you are putting into a wheel transfer to the drive shaft and not the other wheel, it all depends on where it’s getting the most resistance. Isolate what you are looking at as much as possible. A second set of eyes is also nice. Keep working the problem, you’ll find it.
Tim

ah, see you found the problem while I was posting.

 

Make sure the driveshaft isn’t spinning. With the driveshaft locked (either in 4wd or someone holding it steady) and both wheels off the ground, when you turn one wheel by hand the other should spin the opposite direction. Assuming all is well with that test, then it’s fairly safe to say the 4.27 vs 5.38 gearing is your only problem.

 

Did you test drive this vehicle in 4WD after the Dana 30 installation?