81 GMC K30 Transfer Case and locking hubs
 

The transfer case and hubs seem to be stuck. I can not get the transfer case out of 4H and the locking hubs will not turn freely. They were both working fine when I bought the rig. I have only owned this truck for 2wks now and I am not familiar with anything yet.

Any help getting familiar with this issue would be great. I think it is an NP205?

Re: 81 GMC K35 Transfer Case and locking hubs
 

unless someone swapped it k30 in 81 will be a np205 .

if your in 4wd and on pavement it can be tricky to get them out . do the t-case first . then the hubs . also try undoing this stuff on grass or gravel it can help the bound up problem . and wheels stright .

its also a good idea to get some spray oil and lube the linkage under the truck for the 4x4 shifter . the pivot bolt might even have a grease zerk .

stock single lever np205 shifters have always been a bit cranky . i swapped to a aftermarket twin stick years ago and it shifts WAY better . i will never go back to a single lever again . i got mine from offroad design .

for spray oil i like napa 1370 chain and cable lube . goes on thick foamy and turns sticky oil to stay in place and takes months to dry out .

and nice k30 truck and boss v-plow . she will be a tank for you .

Re: 81 GMC K35 Transfer Case and locking hubs
 

If it has lockouts there is a good chance it's a NP205, however without seeing the shifter or transfer case this is only a guess since you can convert NP203 to part-time as well.
My guess is things are bound up and won't unlock (if nothing is broken). Put the trans in neutral on a level surface and you should be able to get the transfer case out of 4-hi. Usually rocking the truck back and forth by hand will relieve the tension on the drivetrain and you can unlock the hubs then too. I have this same issue with my '74, just have to rock it back and forth a little and then you'll be able to unlock the hubs again.

Re: 81 GMC K35 Transfer Case and locking hubs
 

Not much help here but she's probably beyond repair. Your best bet is to sell it to me and I will gladly come pick her up. :lol:
Btw, curious about what's on the hood?

Re: 81 GMC K35 Transfer Case and locking hubs
 

Back her up and it should pop out of gear

Re: 81 GMC K35 Transfer Case and locking hubs
 

Changed the gear oil and took apart the Hubs (Spicer Hubs) cleaned the gunk out of them, lightly greased and reassembled today. Drove around a little bit, parked on level gravel and everything seems to be working fine. I will have to go back and look for a zerk and lube linkage.

Thanks for the tips.

Re: 81 GMC K35 Transfer Case and locking hubs
 

no problem .

and KEEP them spicer hubs . there BEFFY as he!! . and if they ever did fail they fail locked unlike warn hubs and some other brands .

Re: 81 GMC K35 Transfer Case and locking hubs
 

It definitely is NP205.

Re: 81 GMC K35 Transfer Case and locking hubs
 

I should at least drop more money into it than it is worth first though, don't you think?

It was originally a firehouse rig. That is the no. 81 on the hood.

Re: 81 GMC K35 Transfer Case and locking hubs
 

That's what I thought when I had them apart but it just didn't register completely. Good to know. Thanks.

Re: 81 GMC K35 Transfer Case and locking hubs
 

Nice rig.

Re: 81 GMC K35 Transfer Case and locking hubs
 

You beat me to it. KEEP your Spicer hubs. They're tough as hell. Nothing like em is made anymore. Just keep em clean and lubed.
If the plastic centre breaks all is not lost. There's a writeup on how to fix it with Polyvinylchloride pipe and Epoxy

Re: 81 GMC K35 Transfer Case and locking hubs
 

Thanks for checking in on this. I appreciate the conformation. I never even heard of Spicer Hubs before.

Re: 81 GMC K35 Transfer Case and locking hubs
 

Can you tell me a little more about what an aftermarket twin stick is please? Thanks very much.

Re: 81 GMC K35 Transfer Case and locking hubs
 

These are twin sticks: separates the front/rear so you can use them independently. My 4500/205 combo.

Re: 81 GMC K35 Transfer Case and locking hubs
 

note true . yukon hubs they took the best of the dana 44 style and dana 60 style and combined them and made them better . plus they stick out even less . https://www.yukongear.com/productdet...x?ProdID=11865

next there is this guy who makes new billiet aluminum dials a pair for 100 bucks . https://www.tdsideas.com/store/p6/Da...kout_Knob.html and all sorts of other kool parts .

Re: 81 GMC K35 Transfer Case and locking hubs
 

yep stock np205 links both rails to give functions . separate them you get rear high/N/low and front high/n/low . you still can NOT mix ranges the like high & low not going to happen .

but if you also mod the shift rail or get a new rail if yours is worn bad then you can go and do front wheel drive option with the twin stick . this is more for offroad trails and such .

here is the link to ord web site page for there kit . its a basic bolt in kit in a hr or 2 for the average wench turning truck guy . http://offroaddesign.com/catalog/NP2...ckShifters.htm

i twin sticked my plow truck years ago and loved it . way better shifting and feel .

bonus if you do trailer is backing up in 2WD LOW range option with just the twin stick lever kit . yes this can be done stock single lever also if hubs are unlocked .

if you wish to get real crazy i did 6 levers in my 1 project thats not done yet . and the trans has a bell crank linkage to work correctly with it set so far up on the trans . fits threw a stock 4 speed shifter hole with 4 speed boot .
1= lokar auto trans / 2-6= winch in/out / hydro pto pump on/off / range box high/n/low / 205 rear high/n/low 205 front high/n/low

Re: 81 GMC K35 Transfer Case and locking hubs
 

Those are fairly recent replacement parts because this generation truck is gaining popularity.
Once you have the CNC program for milling the knobs it's not much of a leap to build a program for a negative of the knobs to make Injection molds for ABS or HDPE knobs.
The reason I'd stick with plastic, if possible, is Aluminum has a nasty habit of corroding when it's in contact with Iron or other metals. The plastic knobs have lasted 30+ years. Not so with the Aluminum knobs on my long gone 1969 IH Scout 800A or my 67 Dodge pickup in the barn.

Re: 81 GMC K35 Transfer Case and locking hubs
 

I just checked out offroad design. Oh my my! What am I getting myself into? This is going to become another expensive hobby. I think I'm going to have to trade in some old hobbies for this one. I thought I knew something about offroading....not!

SunSoaked, I'm not exactly sure what a 4500/205 combo is yet, but I'm guessing I might like to have one of those. I have some other rigs like a 79' Suburban that has a 400cid/Th400/203 I was wanting to make into a back road bush truck, but now I'm thinking GM Crew Cab short bed rather than a Suburban body (I have 4 young boys that don't drive yet) because if I was to put all these things together (with like a 203/205 doubler) and go where I want to go, I'm guessing the frame is going to twist a little.

For now I just need to concentrate on a drivable/bulletproof plow truck.

Do I ask about other issues on this thread or create a knew one? or a search?
I need a good old Rochester Quadrajet builder, not a reman piece of junk. Any help/advice here would be great.

I also think I'm going to have to figure out a way to make more money. Legally of course.

My apologies to all respondents. I am new to forums in general and have never engaged with anyone and still learning how to correspond properly. So to everyone, Thank You! and keep it coming. I'm just getting started.

Re: 81 GMC K35 Transfer Case and locking hubs
 

Sorry Sweetk30, just noticed your post. You guys are killing me! I getting goose bumps thinking about all the fun I'm going to have with my boys and hives at the same time thinking about all the info/research I'm going to have to digest. Love this stuff!

All I can say is thank you for all for the informative posts. I figured this was a good forum but I truly just took a blind leap of faith hoping not to get engaged with a bunch idiots. I am pleased to say this Forum and you folks are awesome!

Now I have to make time to try and to comprehend everything. I will do my best to keep up.

This 81' is an amazing old rig. However I'm still working on little things too, like wiper motor switch, bad plow connections, heater controls, slow electric window motors, carburetor (this one is the most painful), power steering pump/hydro boots etc...you guys know the stuff.

My main concern and interest is the drive/power train so thanks again!