Transfer Case - Only have 4L (Dana 20)

Roger that, just figured I would ask. Jeff, I did not check the rear drive shaft. With the transmission tunnel access cover off I could verify that the front drive shaft would spin in 4l but neglected to check the rear drive shaft. Would you recommend jacking up the rear of the truck and trying to spin it by hand?
 
Hahaha, are you sure????? I'll do that first thing this evening. Can't believe I neglected to do that. I tend to get hung up focusing on the component giving me trouble instead of stepping back and considering the entire system. Lesson learned. I'll report back this evening.
 
Kinda late for that, now that ya got it torn apart.

Good ole po virus bit ya in the rear.

At this point I might consider, out of curiosity, and install your spare to see if that solves the issue. But I'm think there might be a bigger problem, that just a possible bad rebuild of the tranny, along with not mating things up properly during the previous install.

Also, as mentioned, it be good to jack up rear-end. Checking the prop shaft and diff. Hope ya got yourself a decent pair of stands. Would hate to here that ya got squashed.
 
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Yea, it would not be the first time a po removed the rear diff gears to facilitate a quick sale. It wouldn't explain the missing 4h though.
 
Haha but the po seemed like such an honest person! Haha just kidding, there have been some undisclosed issues but I knew I was buying a project. Its slightly therapeutic after spending my 9-5 hours behind a desk.

Ok, rear end jacked up, spun the wheel ends and the rear drive shaft spins freely. I don't sense any binding, grinding, etc. All seems well. I'm going to bite the bullet and commit to installing the 'good' transfer case tomorrow and see what happens.
 
Well I had a buddy help me wrestle the 'good' transfer case into position last night and....drum roll...it shifts properly! I still need to hook up the drive shafts and fill 'er with fluid but seems to be a-ok. I'll take it for a test drive soon to be sure. My next project will be to tear into the 'bad' case and do some detective work. I've got the service manual so that should help me find the issue.
 
Welp, fix one problem to discover another. The transfer case now shifts great, goes through all of the positions flawlessly. Got into the truck to take it for a spin and it barely moves. It acts just like it would if the parking brake were engaged. I have to rev it to like 2000+ rpm and then it just barely inches forward or backward. It acted like this before the transfer case issue but I just assumed it was because it was in 4l. So now I’ve got to troubleshoot that. I know the parking brake disengages because I jacked up the rear axle and spun it a few days ago when the transfer case was out and it was no problem. In fact, I had the parking brake on when I first tried it and the wheels wouldn’t spin, remembered the parking brake, released it, and they spun easily. Also while I was tightening the driveshaft bolts I was able to move the truck forward and backward by myself while underneath the truck, so I assume this isn’t an issue with a binding drivetrain.

I’ll start with the easier stuff. I’ll make sure the front axle spins freely in 2wd, maybe the front brakes have locked up but I doubt it since I was able to move it forward and backward by myself. I’ll also check the fluid level in the auto. If all that checks out, I reckon I’ll make sure the bands are adjuster properly, the po did take the trans out and ‘rebuilt’ it. The fun continues…
 
If you were able to roll it freely by hand you're front end isn't hanging up. Given the symptoms and the latest revelation about po fixifying on the trans, I strongly suspect as I think you do too, that the trans ain't happy. Hopefully it is just a simple fluid level issue. Do you know the proper method for checking the level? Speak up if you don't. There's one right way and everything else is wrong. Accuracy does make a difference.
 
Yea, in my travels around this board I stumbled upon the proper method for checking the trans fluid level and I bookmarked it so I'll be sure to follow that. I'll give you one observation that makes me wonder about the front brakes. I had to install a new master cylinder because the last one was toast so I bench bled it prior to install but then before bleeding the rest of the system I went through my ignition issues (thanks for the help there scoutboy74) and got the motor running. When I then got around to bleeding the brakes, I loosened the bleed screw and fluid gushed out (happened on both sides), not under extreme pressure by any means but more so than I expected. Almost like there was slight pressure in the lines. I'm wondering if my front brake line(s) have collapsed a bit and is restricting flow back to the master cylinder. I'm thinking that I was able to roll it 'by hand' during the transfer case fiasco because it had been sitting for over a week without the pedal pressed so maybe the pressure was relieved…slowly. I know it’s a bit of a stretch but its easy enough to check. I’ll keep the truck in 2wd and jack up the front to see if the wheels spin. I expect success there so then I’ll start the motor up / pump the pedal a few times, give it a minute or so and then try to spin the wheels again. I think it’s a good idea to check the auto trans fluid level regardless of what happens with the front axle but something about those front brakes makes me want to investigate, if nothing else to prove to myself that it checks out. Of course the work of the po on the trans makes me even more suspect of that but hey, I guess I May just be doing that manual trans swap a bit earlier than expected. That’s how working on 40 year old vehicles goes some times!
 
Sounds like you're on top of it. I would think that if one or both front calipers were stuck and the trans was healthy, the truck would still want to lurch either forward or rearward to the point of rear wheel spin and dragging of the offending locked wheel(s). You got a daggum stump pullin' torque monster motor under the hood. If the trans is capable of transferring that torque to the rear wheels, it's going to try hard to move the rig, locked up wheels or not.
 
I know this has gotten well off the transfer case topic but I'll go ahead and post what I've found which I am sure is causing the issue. The automatic transmission was a bit thirsty. And when I say thirsty, it was a gallon low. Yup, gallon! Since the po 'rebuilt' the transmission, I assumed he properly filled it with fluid. You know what happens when you assume. The front brakes were sticking and everything is in pretty awful shape so its all getting replaced, I hope to enjoy this truck for many years so why not do it right....especially since the po said he re-did the brakes which consisted of new brake pads and apparently having some local beaver turn the rotors...shame.

As always, thanks for the help!
 
Welcome to the wonderful world of po virus. I was somewhat suspect of the trans in the beginning, but had hoped for better. I suggest pulling it and have it rebuilt. If it was me at this point, I don't think that I would waste the fresh oil if it's already having issues.

Same goes for the brakes. Hate to see you become a rocket through someones rear bumper.
 
I say go ahead and run it once you get the brakes squared away. Now that the fluid level is proper, the thing might be pert as a ruttin' buck. Would be a shame to put the cart ahead of the horse if you don't have to. Worst case is you wasted a gallon of atf if the trans turns out to be in need of service. I know it ain't cheap, but boo friggin hoo.
 
Yea completely agree, I'm going to give it a go and see how the auto holds up. I never intended to take this thing cross country so I'll cruise around town and keep my eye on it. Like I mentioned, I've got a donor manual trans that I'm looking to swap this next winter so hopefully the auto will hold up until then. If not, I'm a aaa member haha. Thanks again, the brake parts have started showing up at the front door and I've gotten the old stuff torn down and off the truck so I'm really hoping that this is the last hurdle to jump to start enjoying it.
 
I couldn’t help but post one more update. Does anyone want to venture a guess as to why the transmission was low on fluid? That’s right! It had a leak, I just didn’t know that because it had leaked down past the leak point ever since I had the truck which is why it didn’t Mark its spot in the driveway. It was leaking from the beloved shifter seals. $4 in parts from napa and about 8 hours later and its holding fluid and running like a dream. This is the first time my wife and I have actually been able to take it on a drive since we bought it 6 months ago! Thanks to all for the help!
 
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