1980 Sierra K15 NP205 Stuck In Neutral

[Bextreme04]

No, I did some checking. The truck is for certain a 1980 model, however the TC, and it is original, is a 203. They must have been emptying the old stock as this one was rolling down the line.
The issue was definitely linkage related.

I doubt it was the original. The trans and T-case probably got swapped over when the engine did. Do you have a pic of the SPID sheet in the glove box?

 

[GTX63]

It is a 203 and full time 4wd. I agree, it is possible it was swapped out, but from making contact with the last two owners, and the exterior appearance, it would have been a very long time ago. The RPO list is also gone.

 

[nvrenuf]

Crawl under and clean the tcase, there will be a metal tag stuck to it with the year on it. Be prepared to discover it's swapped in.

 

[Bextreme04]

Yep, probably the trans too. Mine has a partial vin on the passenger side, I'd look for that on the trans as well. Be prepared for that to not match your truck either. Does the VIN on your truck match what you would expect for a 1980? What is the first part of the VIN(first 7 digits)?

 

[AuroraGirl]

A 1980 half ton did not come with a 203
I’d be curious what the truck frame vin says for year and compare that to your SPID/title, and then compare that to your dash plate by windshield. Do you have glass or plastic fuses, and does your axles have the word SPICER or WARN on them?, pics if possible?

Or is the axle end a cover with no knob?

 

[AuroraGirl]

A 208, which is also incorrect for 1980, would be easily mistaken for 203 if it was stamped lightly or had corrosion or even dirt in the tag.

Can you take a pic of your case from under the truck, and can you take a pic of the shifter?

A np203 is big. An np205, also cast iron, is not as big but under a vehicle the size appearance could be misleading when comparing, for example.


A np205 from 1980 should have a slip yoke to the rear driveshaft and a fixed front output. I don’t recall what np203 does but the rear output has a unique shaped cover piece that has the speedo cable I believe..
np208, aluminum cased, should have a slip yoke. The housing is quite long at least from my memory

 

[GTX63]

Be prepared for that to not match your truck either. Does the VIN on your truck match what you would expect for a 1980? What is the first part of the VIN(first 7 digits)?

Lol, the short answer is "No".
Having owned quite a few SB trucks, this one is becoming a head scratcher and yes, it does have me questioning myself.
As far as I can confirm, I am the 6th owner. Supposedly, the 2nd owners, two brothers who farmed, pulled the original 250 6 cylinder in 1989 and installed a 1978 drivetrain. I do not know from what.
The motor was a 350, that was all I was told. Corporate blue, Q jet, nothing aftermarket.

The glovebox sheet is long gone. The VIN code 2nd digit is a "C" indicating 2wd, lol.
Once the sun rises, I'll check the block code and slide under the truck again for pics. There is no tag on the transfer case.
The truck came out of the Lakewood Ga plant, spent time in Alabama and Southern Kentucky. The body looks like it was buried in a Michigan salt pile.

 

[GTX63]

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[Strick]

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The shifter pictured is for an NP203 full time case. The truck should have the slip yoke NP205 for 1980, as was mentioned earlier.

Strickland

 

[GTX63]

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[nvrenuf]

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Did you ever check the year on the ID tag?

 

[AuroraGirl]

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1991+ trans dipstick (could be retrofitted so not an issue)

 

[Strick]

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NP203

 

[Bextreme04]

That's a 1980 front end for sure. It's one year only. That's also definitely an NP203. Now you just need to take a pic of the trans pan so we can tell you what trans is in it, but I would bet it's a TH350.

At this point, my best guess would be that someone took a 1980 body and dropped it on a 1978 K series frame and drivetrain.

 

[GTX63]

That's a 1980 front end for sure. It's one year only. That's also definitely an NP203. Now you just need to take a pic of the trans pan so we can tell you what trans is in it, but I would bet it's a TH350.

At this point, my best guess would be that someone took a 1980 body and dropped it on a 1978 K series frame and drivetrain.

Yes, the transmission is a TH350. I would agree that is beginning to appear like the body was set onto a 4wd frame, I just can't wrap my head around why. Non of the previous owners I tracked down mentioned it.
I'm replacing the bed, rockers, cab corners, front fenders and wheel wheels. Unless this old girl turned from Cinderella into a rusty pumpkin overnight, why? How bad could the other body have been, lol?