So about last week my 1980 F100 with a dana 44 ttb manual locking front end, C6, and 13-56 Borg Warner Tcase started to make a grinding/groaning noise so bad I could feel it in the floor board. It does it every once in a while as I'm going down the highway at about 70 and it gets more frequent when I slow down till about 50. To me it sounded like it was coming from the right front wheel so I pulled it off and sure enough it showed signs of leaking grease around the cap seal. Today out of couriosity I removed the front drive shaft. With the Tcase in 2H and the truck off in park I grabbed the front yoke and it free spun as I suppose it should. I then put it in 4H and it still free spun and when I spun it forward to reverse it made a clunking sound like something was hitting the case so I thought "oh great my Tcase is done". Next for poops and giggles I cranked it up and drove it. Not once did it make the noise. I put it back in the driveway in 2H in neutral with the brake set and the front yoke free spun like I suppose it should. Then with it still running and in neutral with the brake set I put it in 4H and tried to spin the front yoke. Nothing. It didn't spin at all like I'm geussing it shouldn't because it is meshed with the gears and ready to spin the front. I am completely confused as to what is going on because I am new to 4x4 but I believe it is the front hubs, correct me if I'm wrong. Also my Tcase shifter is a little tricky to find the different gears. When I go to shift into 4H it feels like all the gears go by in one click and sometimes it will pop out of 4H while driving. It is especially hard to get it into 4L partialy because it the seat is in the way.

Sorry for the long write up but this is freaking me out and this is my daily driver. Thanks, John

 

When you are driving down the highway at 50 or 70 and get the noise, do you have it in 2H or 4H?

As for the front yoke, it shouldn't spin in 4H or L, but should in 2H.

But, if you can't get it to go in gear correctly, assuming you have it in Neutral when trying, then maybe you have a problem in the t-case. I had a similar problem with an NP208 and the shift yokes were worn out.

 

When it makes the noise going down the highway It is in 2H. I don't ever shift it into 4x4 untill the tires hit mud or dirt because I am afraid of it binding and breaking something.

As for shifting it, when the truck is on and in drive It will go into 4H/2H and stay there but not 4L. When it is off,it still won't go in 4L and feels like it won't stay in one gear and it is hard to tell which one I am in. I have only had it pop out once. It grinded and wouldn't go back into 4H so i had to put it in park. When I shifted to park it made a bad grinding noise until it finally felt like it grabbed park and stopped. I put it in drive and it shifted right back into 4H and off I went. It never came back out. From then on until now I havn't had any problems with it. Also I remember vefore this started I removed the ***** you turn on the locking hubs to paint them and they were a little tricky to reinstall but I thought I got them back in correct. Could these not being in right cause this?

 

You are doing things correctly as you aren't supposed to be in either 4H or 4L on pavement with the front hubs locked in. Good job.

But, speaking of the hubs, it is possible you didn't get them back together correctly. You should be able to find an exploded view on the Internet, but I can find one tomorrow if you can't.

On the t-case, if it pops out you have a problem. I'm not sure it is the problem that is making the noise, but a problem nonetheless.

As for the noise, did you drive it with the front drive shaft out? If so, did it make the noise? If it is the hubs it should make the noise with or without the front shaft.

 

I did drive it without the front driveshaft on the highway at 70 for a couple of minutes and it never made the noise but tomrrow I will drive it to school and see if it will make it again or not. As for the hubs, I didn' pull the whole things apart, I just unscrewed the one screw in the center and pulled the plastic **** out, painted it, and screwed it back on. The reason it took a while to get them back in is because the peice they screw onto was loose and kinda pushing in to where the screw wouldn't reach it.

 

Welp, drove to school today without a single noise so it looks like the problem is my transfer case. I would like to get the same one but am willing to upgrade for a better unit. Are there any stronger ones that will fit without different driveshafts? Maybe even an electric shift one? It has to have the rear slip yoke like the one I have so I don't have to work on my driveshaft.

 

I'm told the BW1356 is stronger than the NP208. And it looks to me like the one I have will work with the same drive shafts, although I've not checked that the u-joints are the same size.

The downside is that it uses a bit different shift lever. But, I'm hoping the one for the amap will work.

 

Well, today I was driving to school, still with the front driveshaft off, the truck started to make the noise again. I don't know what this means but I need to figure it out soon before whatever it is goes out and I lose my rig. Does anybody know what this could be? I'm thinking its either the transfer case or the front hubs.

 

With the front drive shaft off you can engage the front hubs. If the sound still happens then it probably isn't the hubs.

 

Welp, today to and from school I drove with the front driveshaft off and the hubs locked. I didn't hear a single peep. This means it is the hubs correct? I don't mean to bash the 4x4 world but I'm thinking it isn't really my kind of place. Every since I made the swap I have kind of regretted it and now with these problems it is really starting to push me back over to the 2wd side.
If anybody has a ball joint 5x4.5 F100 front end please let me know. Also If you are interested in 4x4 we could possibly make a deal for my Dana 44 ttb front and C6 Tcase if you are close to Caldwell, TX

 

If you have the noise with the hubs unlocked and don't with them locked then it must be the hubs. (Had it been the other way around it could have been the u-joints in the front axles.)

 

Replacing the hubs sounds cheaper than buying a nee transfer case thats for sure. Thanks for all your help I am very greatful!

 

I'm happy to help, but I just hope the diagnosis is right.

 

Do you get the noise when you let off the throttle or when the truck is coasting? In the transfer case, there is a fork that moves what I call the reduction gear set back and forth. When you go to 4L, this set locks to the transfer case housing to change the gear ratio. On the front of the setup, the forks set in a plastic (or some type material) slot. If the plastic slot is wore out, the forks no longer load the gear set and it will move back and try to lock on the transfer case housing while turning. Not good and makes some noise.

The good news is it doesn't take a replacement transfer case to fix this. Just some parts. Really the insides of the case are simple if you are mechanical inclined. You could also check with your local transmission shops. Some will work on them, some will not give warranties.