Author Topic: 4x4 Guys... Need some help - Trans. Swap  (Read 5813 times)

Offline HAULIN IT

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4x4 Guys... Need some help - Trans. Swap
« on: October 07, 2014, 08:02:57 PM »
Guys, We have this P.O.S. '82 3/4 ton pickup @ work we use to plow snow in the lots. It never leaves the property & winters aren't real bad in Pa. like they are in some "snow belt" areas of the country, so it isn't something we use allday-everyday, but it serves the purpose, but isn't worth much or much effort. Here's the basics...several years ago we installed one of the low-end GM crate 350's, it has the stupid 4 speed (SM 465) & a 208 transfer case.
The clutch linkage is all shot, wore out, ect. & plowing with a stick is a real pain particularly in rather tight quarters around vehicles, ect. so I was kicking around swapping out the manual for an auto.
I did this swap a few times YEARS ago using TH350's & either a 203 or 205 depending on the parts at the time. I remember the manual having a 10, maybe 14 spline output shaft so I swapped the T'case out to match the TH350. I've not done much with 4x4's newer than '79 so the 208 stuff is "new" to me.

So the questions: The column appears to be the "old" non-wiper/dimmer version...Is it the same as a '78? Seems I remember something @ the firewall area being different where the shaft goes on heading to the box changed around '79 or so?
So is the column a direct swap...electrical plugs, lower shaft hook-up, ect. or do I need something newer than the '78?

What spline (assuming this is in fact all the "correct" '82 parts, is the trans output shaft on the manual?
Is there any auto trans that goes directly in place of the manual?
I seem to remember hearing that the trans output shaft length being longer for the 208 than when used with the 203/205?
Does either the 203 or the 205 come out the same with the front driveshaft, Rear...if using a TH350 in place of the SM465 & 208?

I have some parts stock piled (TH350 with output shaft for the 203/205, a 203 case, a 205 case with slip yoke output from a '79-'80 Blazer, an Advance Adapters spacer/mount to put a TH350 in place of a 700 r4, a '78 auto column & some other stuff I'm sure hiding here or there) & can use some of that if it will work, but I want to do this as easily & cost effective as possible. I want to avoid building 2 driveshafts, ect. if I can as the ones in the truck are fine. Getting a working trans. isn't a problem as one of my best friends owns a tranny shop, but I would want to have the correct hardparts collected when we go to building it.
So help me out guys...What is the most logical way to go about this? Thanks! Lorne
   

Offline roundhouse

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4x4 Guys... Need some help - Trans. Swap
« Reply #1 on: October 07, 2014, 11:56:08 PM »
I'd find a donor truck and grab the trans and t case and flywheel flex plate driveshafts etc

GM put  so many trans/ T-case  combinations in these trucks it would be a real scavenger hunt to find enough parts that actually fit together

Unless you find a cheap donor truck I wouldn't brother with the swap unless you want it bad
You will spend way too much time rounding up parts that may or may not fit together



Collum should be the same
I  recently swapped a 82 tilt Collum into a 76 and it bolts in.  The switch box at the bottom was reversed.

I do t remember which but on one model the switch pulls the rod to work the switch and the other model pushes the rod


I'm
Not sure when they Moved the wiper switch but it was after 82.  Or at least my 82 has the switch on the dash
But it's the same switch. You just unbolt it and flop it around and plug the wires back in

Your manual trans Collum should be worth a few bucks
As are the granny gear trans

Which I agree would really suck for a plow truck

It sucks for any truck

Can wait To swap mine out with a nv3500 5 speed
« Last Edit: October 08, 2014, 12:01:28 AM by roundhouse »

Offline fitz

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #2 on: October 08, 2014, 06:14:25 PM »
A cheap aftermarket floor shifted may be quicker then a column swap.
Roundhouse is right about finding a donor truck.
In Mass I can find parts trucks in the $500 range. That way you know you will have all the parts.  You can pull all the parts you need and scrap the shell for $400.

Offline Captkaos

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #3 on: October 09, 2014, 06:31:40 PM »
The wipers went to the column in 1983.
The SM465 4x4 version had 2 different output spline counts
Pre -1982 2-1/2” stick out/10 spline
1982 - 83 for NON NP205 had a long 32 spline output, NP205 kept the 10 spline
1984 - 91 had the universal long 32 spline output for both NP205 and NP208.

Direct replacement of a Manual isn't really available as the early ones are going to be really short.  Ideally you need the trans/transfercase pair to go in.  The TH350/NP205 would be the shortest, but finding those is going to be difficult if not impossible.

All the 73-87(91) front outputs will be the same, but the lenght difference is going to be there but most had a slip shaft, so...

Offline Blazin

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #4 on: October 09, 2014, 07:42:17 PM »
I would just replace the linkage, or weld up the holes, and shafts. Tighten the old stuff up. I have plowed with an SM 465 for years. I get turned around in tight spaces all the time. Plow right up against /  near stuff allot.
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline roundhouse

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #5 on: October 09, 2014, 09:41:02 PM »
The linkage has bushings in every joint and pivot

I think there are 3 under the dash and 3 under the truck for a total of 6

If they all have some play it adds up


Replacing those would go a long way twards getting it easier to shift

Offline HAULIN IT

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #6 on: October 10, 2014, 07:22:47 PM »
Ok Guys...Thanks for the replies. Chris, From your answer, I'm gathering that the '78 column is a direct swap to the '82? Wiring plugs, Lower shaft coupler & all?
Your comment about the front shafts...Are you saying ALL front shafts are interchangeable...'73-'87 reguardless of manual, which auto, 203, 205, 208? If so...I sure didn't realize this!
From the info I'm getting, I have everything I need except maybe the rear driveshaft to do the swap. I'll have to look @ my stockpile a bit closer, but it sounding like I'll probably do a TH350 & a part-time converted 203 that I have. I would use one of the 205's I have if it would have been a direct interchange, but if not, no sense in "wasting" one on a lot truck. Thanks for the help, Lorne

Offline Captkaos

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #7 on: October 10, 2014, 09:12:42 PM »
Same as in if it had a 208 regardless of the trans the shaft would be the same.
As for the column, yes it should swap out fine.  I think that is the year that the shaft changed, but if you are swapping all of it out, it won't matter.

Offline roundhouse

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #8 on: October 11, 2014, 11:25:05 PM »
When we swapped the 82 Collum into a 77 we also had to swap the rag joint


Offline HAULIN IT

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #9 on: October 12, 2014, 03:33:08 PM »
When we swapped the 82 Collum into a 77 we also had to swap the rag joint



Ok, Thanks. I remember years ago I was involved with some swapping this to that stuff & remembered there was something about the set-up @ the base of the column being different where the lower coupler goes on...the newer is splined & the older has a rectangle stamped into the end of the tube or something like that. As Capt. memtioned...If you have the whole thing (column & lower shaft) it goes in, which is what I remembered it. I'll have to see what the '82 has...I may need to hunt down a lower. When I changed to a tilt/cruise column in my 4x4 (from a '79-'80 Blazer), I just got the column, so I have the non-tilt from it ('78) to use in this truck, I re-used the lower at that time without issue. Lorne

Offline Irish_Alley

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #10 on: October 14, 2014, 11:32:29 PM »
capt im confused about input shafts are the same. but thought the year for the "round" pattern 205 started in 85 and these are the ones that got the long input shafts
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Offline roundhouse

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Re: 4x4 Guys... Need some help - Trans. Swap
« Reply #11 on: October 17, 2014, 06:26:17 AM »

When we swapped the 82 Collum into a 77 we also had to swap the rag joint



Ok, Thanks. I remember years ago I was involved with some swapping this to that stuff & remembered there was something about the set-up @ the base of the column being different where the lower coupler goes on...the newer is splined & the older has a rectangle stamped into the end of the tube or something like that. As Capt. memtioned...If you have the whole thing (column & lower shaft) it goes in, which is what I remembered it. I'll have to see what the '82 has...I may need to hunt down a lower. When I changed to a tilt/cruise column in my 4x4 (from a '79-'80 Blazer), I just got the column, so I have the non-tilt from it ('78) to use in this truck, I re-used the lower at that time without issue. Lorne

Yes.  The lower shaft is different

But if you grab the entire deal it swaps Over fine

You just swap it at the rag joint