72 Jimmy 4x4 transfer case troubles

[VanceH]

Ok heres the deal, i have a 72 jimmy with a automatic. I am assuming its a turbo 350. I just lost the transfer case and had to be towed home. I am wanting to replace or fix asap as this is my daily driver. Does anyone have any ideas what transfer case this is? How hard is this to rebuild

Thanks
Vance

[JimmyFloyd]

my guess would be it's a NP205, but don't quote me.

[mrein3]

Make sure you get one that was originally behind a th350. The straight stick 205s have a different input shaft.

[D.PASSMORE]

Is it the T-case (NP-205) or the transmission (TB350)? Have you been able to determine which it could be causing the problem? Snaps some pictures, so it can be ID'd the units... There is plenty of rebuild info and kits available.

[Thealien]

Why do you think it is the transfer case? Those NP205s are pretty tuff!

[VanceH]

ok after getting underneath the rig its the u joint on the Transfercase side. (i think) But it does not look like any u joint i have ever seen. seems different. is there a special u joint on these? Sorry this is my first 4x4 i have owned in this year.

Thanks

[sharpie1972]

Please keep us posted on parts needs. Pictures would be helpful. If you haven't damaged a yoke or driveshaft this should be an easy fix. Sharpie

[VanceH]

I will post up pics in the morning, as its to dark now. I am trying to find the u-joint or a pic of it but i have seen nothing like this before. Its almost like a sleeve of some sort?

[sharpie1972]

Sounds like the "slip joint" might have let loose. This probably calls for a driveline rebuild or replacement. Still not nearly as bad as losing your trans. or transfercase. Any sign of damage to the transfercase yoke or housing? Sharpie

[VanceH]

No damage on the transfercase at all, i looked thru some documents that i have when i bought the jimmy. it shows a rebuild on the transfercase with less than 10k ago. So i will take the driveshaft off in the morning and see what is what

[sharpie1972]

Let me know how bad the damage is. I have two original shafts and may be able to get you back on the road. A rebuild of your original is the best option if it's not too mangled. Sharpie

[VanceH]

ok i found a pic, this is not mine but this is what i have. Am i correct that there is 2 u-joints on the transfer side

[sharpie1972]

Oh Boy! that is modified to the max. You have a driveshaft park brake set-up. Not factory, but very functional. I say you have 2 choices: Rebuild what you have or go back to stock. The problem with stock would be the cost/trouble of replacing a factory park brake set-up. You may be money ahead to fix what you have if it is not totally destroyed. Sharpie

[VanceH]

like i said this is not mine just a pic of what my ujoint set up is. I dont think i have the same brake setup. is the h joint factory on these?

[D.PASSMORE]

What are the symptoms of the problem with the drive line?

[BLAZERMAN]

Thats a CV joint [constant velocity] and would be normal for the transfer case side of your front driveshaft but not the rear.

[72lb4x4]

If the TC is in 2H and you have unlocked locking hubs, why is the front driveshaft an issue?

[VanceH]

not sure how the whole 4x4 thing works, i think i have a hub stuck in the locked positon or somthing. The front drive shaft turns when the truck moves. It happened while i was driving 60 on the highway. all of a sudden BANG BANG BANG so i stopped and had it towed. The shaft looks good but there is about an inch play in the CV or H-joint. I will pull it off in the morning and take a bunch of pics. Does anyone know if this takes a standard Ujoint?

[FLEET72]

That is a "double cardan joint"


a little tougher to repair but very doable in the driveway or at the rest stop 20 miles east of Phoenix on I-10 in the middle of summer.

[FLEET72]

Originally Posted by VanceH

not sure how the whole 4x4 thing works, i think i have a hub stuck in the locked positon or somthing. The front drive shaft turns when the truck moves. It happened while i was driving 60 on the highway. all of a sudden BANG BANG BANG so i stopped and had it towed. The shaft looks good but there is about an inch play in the CV or H-joint. I will pull it off in the morning and take a bunch of pics. Does anyone know if this takes a standard Ujoint?

Check this

[msgross]

you should be able to go into NAPA and get new u-joints for that. Find a buddy with a vice and it can be done in a few hours. Or take it off and have a mechanic fix it...

Is the Transfer Case in 2WD? If so the front driveshaft shouldn't be turning...

[VanceH]

Hey fleet thats it!!!! thanks again for all the help ill post up pics in the morning

[FLEET72]

Also, if it is the front drive shaft just take it off and you can still drive it as needed til the shaft is repaired . If it is the rear shaft you can still drive the truck, just pull the rear shaft, put the transfer case in 4H, lock the hubs and off you go. I drove my K5 that way for a week while having a new rear shaft made up.

[D.PASSMORE]

When you get it apart, pull the yoke out of the rear of the T-case and look at the splines for damage, Also, replace the two seals in the housing. The are notourious leakers. I have part numbers if needed.
Keep use informed, I'm in the process of rebuilding a 72 Blazer driveline.

[sharpie1972]

You may want to clarify if it's a front shaft or the rear shaft that you are having trouble with. I can't quite tell which one from the conversation so far. Sharpie