Dana/Spicer Transfer Case Guapo

I use a high quality long-pattern tee handle hex wrench to access those set screws. Also sometimes I use a hex wrench socket that has had the bit cut down so I can fit a breaker bar in there to break the screw loose.

If someone has been into the case before, they May have used loctite on the screw threads (common practice). If that is the case, you May need to use either a heat gun or a small propane torch and gently heat the boss where the screw threads into the fork in a very local manner to aid in breaking the loctite bond.

The only secret is having a high quality, tool steel hex wrench, not the typical chinee shit found at the discount house.
 
Well, I've heated it with a propane torch for a while, didn't work. I tried a longer allen key, didn't work. (the allen wrench would flex too much before I run out of space to turn.) I've tried a chapman wrench which attaches an allen key head to a small socket wrench-type thing, and I can't get enough leverage to break it free. This thing is really starting to annoy me. Any more thoughts?
 
Small diameter (just fits over allen wrench) long, strong steel tube? Maybe with a bend in it to give you more room to turn...
 
Get the fork material itself right at the threaded boss a dull red, it has to be expanded significantly for the set screw to break loose.

Grind a hex socket down so that just the stub engages the screw completely so you are not twisting the entire tool, then rig a cheater on whatever you are using to turn it with.

If all else fails, then use the gas axe and cut it off and extract the rail and fork in pieces, it's not worth aggravating the hemorrhoids over. I have plenty of excellent used ones in the stash here.
 
Okay after heating it for a longer period pf time I finally was able to break it free. Now I am debating whether I want to remove the interlock pin or to leave it in. I already have the Dana 20 set up with twin sticks and I use a chain to an eyebolt to keep the rear in 4lo (it has the tendency to pop out at inopportune times). Is it worth removing the interlock?
 
I'd remove the interlock myself since you have the twin stick setup. That is a nanny-state deal anyway.

Since the unit is down for rebuild (I'm assuming), then now is the time to correct the issue with popping out of low range under load. That is normally the result of the poppet springs having collapsed partially, worn detent slots, and worn poppets. If the shift forks show any sign of extreme wear/galling on one side, that is the consequences and should also be replaced.
 
X2.

Stretch or replace the spring.

Take a grinder to the shift rail to make the ball sit a little harder for it to slip out.
 
Dana 18 rebuild questions: I have a '61 s80 with 152ci, Dana t90 mated to the spicer/Dana t18 transfer case. I'm in the middle of rebuilding the transfer case, using the novak master rebuild kit.

1. I took the main shaft and clutch shaft to a machine shop to replace the bronze bushing. The new fit feels too tight. The machinist said it fits the spec of .0627. Can I let this go and assume the tightness will wear the bushing down quickly? Or should it move freely at this spec?

2. I'm also having trouble getting the shaft end play right. Before I put the front bearing cap on, the shaft is plenty loose. After I put the front cap on, I lose all end play and don't have enough play to bother with putting the rear cap on with the shims. I think part of my problem May be that the clutch shaft is not fully entering the main shaft (because of problem noted above) and is taking up all the end play when I replace the front cap. (it's hard to visualize unless you've worked on one of these). The instructions are fairly obvious and I'm certain I have the bearings, bushing, snap ring, etc installed correctly. Am I missing something in this process?
 
Thought I would answer my own question above for others doing the xfer case rebuild. The clutch shaft bushing was too tight and caused any end play to be pushed to the rear when reinstalling the front cap. Thus, there was no end play at the rear cap to adjust. I bought a 1-1/8 inch brake cylinder hone from snapon.com and honed the clutch shaft bushing until the clutch shaft turned free inside the output shaft. Then I followed the end play adjustment instructions in the novak kit and it worked out well. The intermediate shaft reinstall was straight forward. I'll let you know how it all works when I get the tranny and transfer case intalled on the Scout.
 
Thank you for the post Jeff. I had the same problem years ago converting my d20 to a d18; the bushing needed reamed.

Bushings should always be reamed, never honed as the grit can imbed in the bronze. In my case I used a knife similar to using a bearing scraper. The machinist sure could have worked with you better, but you got it figured out.
 
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I have a 72 Scout II, 345 with Dana 20 transfer case. The issue I am having is 2h. The transfer case works perfect in 4l and 4h, neutral is good as well. But 2h is actually 2l. While in 2h I was geared as though in 4l so I jacked up the rig and checked all. 4l and 4h turns all 4's but 2h turns rear but in low range. Any suggestions? The previous owner had the tc rebuilt but my guess, something was done wrong.
 
Is this a twin stick conversion? I don't see any way that 2low is possible with a single stick case. There are two shifter rails in the case. One is for hi/low range and the other engages or disengages the front axle. On a single stick case as most d20's are, the rails are linked together. Low range 4x4 sees the shifter pushed forward which in turn forces both rails rearward. For 2low, one of the rails would need to be significantly further forward out of the case than the other.
 
It is a single stick version. This is my concern. There shouldn't be a possible option to have the low rail in position when the 2/4 rail is in 2 wheel. I am wondering if the rails are switched or are they only able to fit one way. Not sure if a possible sticking rail May be a cause. The system is simple, one forward, one back = 2h, both forward = 4h, both rails back = 4l but no being able to get a 2h is perplexing me.

Thanks for any help
 
So are you able to achieve more ground speed in 4hi than you can in 2hi? What about the possibility of some rotational issue within your rear diff or rear brake drums creating a drag?
 
I have a question on venting a Dana 20 tc.

When I did the rebuild on the tf 727/407 I added the standard hose barbs for the vents in the case and housing.

Do you use the same on the tc? Do you run three separate lines up into the engine compartment, or is it ok to use a tee on the two from the transmission.

Finally what have others used for catch cans and do you run the tc and transmissions into the same catch can.

Thanks
 
The trans lines can be t'd to one catch, but I recommend keeping the t-case vent separate, just in the unlikely, yet possible event of fluid cross-mojonation. Head for your local pick and pull and look for plastic clutch slave and brake master reservoirs that you can fabbykate on to orient them upside down on the firewall.
 
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