NP205 speedo fail and the case seems mounted wierd on my 75 pickall???

Rusty Scout

Rusty Scout

Member
NP205 speedo fail and the case seems mounted weird on my 75 pickall???

Well I double checked all cables and speedo corrector and they seem to function fine. Speedo needle comes to life when speedo corrector(adapter) is driven with a drill motor(slowly in reverse).

So no speedo signal out of the NP205. Is this a common problem? I am hoping that whatever needs fixin can be fixed without removing this heavy case.

Also this case seems to hang way below the frame (about 6 inches) and seems to be hanging from only 2 bolts on the passenger side of the tcase crossmember. Is this normal? Seems like a poor design if it is normal. Needs a strut or something to keep it stable I would think?
 
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The speedometer drive comes from the rear output shaft which has a worm gear on the shaft that drives the speedo pinion (which in turn engages the inner speedo cable). Jack both rear wheels up and put the axle on stands. Then remove the speedo cable assembly and start the engine and put in gear and watch to see if the cable pinion spins. If not, then either the pinion or the speedo worm gear is stripped.

The divorced transfer cases have hung from the crossmember with four hefty bolt-points since the earliest days of the pickalls. And with the exception of the single speed/chain drive unit, have all been the most rugged units available for these vehicles since the mid-50's.

Some versions did have a fore-and-aft stabilizer rod to reduce transfer case "shake" under certain load conditions, but I really don't think it's effective as such. I have one on the beater truck, the t-all does not. It's mounted with rubber "stabilizer bar" isolators at each end. They both shake the tc very nicely when heavily loaded over rough terrain with no problems at all. I've driven the beater thousands of miles on the highway in both 4h and 4l on ice/snow/mud/slush with no issues at all, and that includes pulling the 6500lb. Trailer in those same conditions.

Just today I ran in 4l (front hubs unlocked) for about 100 miles going across hiway 36 from red bluff to fortuna/101 just to be able to pull and stop on those 10% grades.

I've also put thousands of miles of severe offroad use on the beater before it had any sort of lift other than 33" tires. I have high-centered on the tie rod guard on frozen double track rutted snow/ice, but never come close to whackin' the 205. However, the bottom of the case does show some significant impact damage which it's just shrugged off over the last 35 years.
 
I might be crazy but it looks like this thing(NP205) is only only hanging from 2 bolts on the one side(passenger) of the case. Over the driver's side of the case I can see 2 empty bolt holes on the crossmember and can run my hands over the top of the driver's side of the case and there is nothing there holding it up. This May account for my opinion of the way the case is below the frame. I have a feeling that someone was a fixin to fix the speedo problem and then quickly gave up after pulling only two bolts.


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When I get to the bottom of these issues I will do a follow up.
 
Ok I guess my parts catalog was a good purchase because it shows that I am not crazy after all. This NP205 on my 1975 150 pickup hangs from one side of the crossmember only with a single bracket(see #5) ...its got 3 (1/2"nc) bolts to crossmemnber and 2 (5/8"nc)bolts to to case.


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Seems like this case when hung in an earlier IH or a Chevy (like a military blazer) uses all 4 (5/8"nc) bolts on both sides of the NP205 for crossmember hanging. Maybe add this to the list of 74-75 pickall ihc oddball cost cutting measures
 
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I believe two bolts on the pass side and two on the top is what I remember does ur crossmember have any cracks? Mine had a complete corner gone btw mm my t/c has a horrible death shake
 
The parts book forpickalls 1974, 1975 and 1976(some 500s this year) shows only 2 transfer cases. The NP205 and the single speed cable pull one. There are 2 crossmember blow apart diagrams. One for each case. Both setups show only a one piece bracket that connects the case to the crossmember(one for each type of case).

I will do some more hemming and hawing and maybe poke it with a stick before I move on to worry about hidden rust or something else lurking around the corner.

Oh yeah I guess back to the speedo. That would be nice to have one although there is an app for that in my iphone now.

After I run mm's test for speedo pinion movement and find none then I will try and fish out whats left of the pinion.

I did see a picture on the internet of a NP205 speedo pinion and the big hex nut that held it in place. The pinion was metal if I am not mistaken and it appeared that you could remove it from the case without risking getting crushed by heavy cast iron objects. I will try and bust that big nut loose. I could not even see it before cause it was under a layer of grease, cow pucky and fur.
 
I contemplated defecting over to mopar this morning. She was a 93 ram 250 cummins. It had a np 205 married to a a518. Could not do it.

Anyway a quick update on my NP205. No signs of any mounting issues or damage. Bushings still intact too. Looks like I can remove the speedo pinion for inspection by using 15/16 thin wall 6 point socket on the speedo connection on output housing . Too scared to try it yet though. Need truck for a hauling job this weekend and don't need any headaches
 
I was wrong my NP205 hangs from the crossmember with 4 5/8nc bolts. 2 via a brakcet on drivers side and 2 directly to the crossmember on passenger side. I was under inspecting the gross play on my front drive shaft slip yoke and could clearly see the other transfer case bolts. Not brave enough to go after that speedo pinion yet. Maybe I can find a nice IH NP205 cheap and rebuild it. My fear is that the speedo drive gear is in pieces inside the rear output shaft housing.
 
These transfer cases are as bulletproof as any similar item ever built. They take a tremendous amount of abuse to make fail in any manner. Whatcha think a cummins dishes out when it's gotta "controller" dialed up???

Sumbuddys blowin' smoke up yore butt about "cracks". Yeah the case will crack if ya launch the rig into the air off a dropoff and then land it square onna rock shelf with all four wheels in the air (maybe)! I've done that more than once in the beater and had to get winched off high center...no cracks yet and it's run thousands of miles in 4h and 4l.

You are making a big deal out of the speedo drive, just pull the output retainer off and see what is there, then simply fix whatever is broken. Or scruu it and use gps for a speedo.

If only two bolts held these monsters to the crossmember, they would have all fallen on the ground 30+ years ago. Yours is no different from the other 100,000 built. If frame/mount components are bent/cracked, it's because of lack of maintenance over the years, shit gets loose, ya tighten it and replace missing hardware with the correct stuff!

The most severe duty operations these trannys and transfer cases ever saw was in snowplow work with a loaded sandbox in the bed. Constant backing and filling while ramming frozen snow piles, steel posts, buried cars, fireplugs, curbs, and other semi-movable objects. Busted locking hubs were a constant cost of doing business so they ran slugs in the front axle during the plow season. If they could handle that, they can handle anything. That way, the axle shafts and driveshafts/u-joints become the fuse instead of the hubs.
 
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