Sm465 swap

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

K201979

Full Access Member
Joined
Oct 22, 2018
Posts
879
Reaction score
863
Location
Winona, missouri
First Name
Hippie
Truck Year
1979
Truck Model
K20
Engine Size
350ci
By the way, you didnt get hurt on that deal. Just the bellhousing is worth more than that. Did you get the hydro pedal setup with it?
 

WoodzLegit

Junior Member
Joined
May 23, 2020
Posts
9
Reaction score
15
Location
PST
First Name
Bryan
Truck Year
1977
Truck Model
K10
Engine Size
350
i think you'll be ok on overall length/ driveshafts/etc. with that x-member amd the tall cast-iron adapter. my 465 has 10spline out and my 205 is 10spline in on my swap. idk why or exact vintage, but i like. this is for sure the bullet-proof setup. 1 odd thing with mine i've never seen b4 is 2nd, 4th, and reverse ate all hard into the seat and ive bent the dog-doo outa my shifter to get that. any ideas where that 465 shifter came from?
 

K201979

Full Access Member
Joined
Oct 22, 2018
Posts
879
Reaction score
863
Location
Winona, missouri
First Name
Hippie
Truck Year
1979
Truck Model
K20
Engine Size
350ci
i think you'll be ok on overall length/ driveshafts/etc. with that x-member amd the tall cast-iron adapter. my 465 has 10spline out and my 205 is 10spline in on my swap. idk why or exact vintage, but i like. this is for sure the bullet-proof setup. 1 odd thing with mine i've never seen b4 is 2nd, 4th, and reverse ate all hard into the seat and ive bent the dog-doo outa my shifter to get that. any ideas where that 465 shifter came from?
The sm465/np205 is for sure bulletproof. They went to 32 splines in 79, which i guess is stronger than the 10 spline setup. As far as your shifter, maybe its out of a heavier duty truck? Or maybe engine mounts are farther back? Was the engine swapped?(i6-v8) im not sure on the engine mounts, but i know there are different configurations. Did the zbar linkage all line up?
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
30,446
Reaction score
28,348
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
They went to 32 spline and no coupler shaft in '81, but only the 208 equipped trucks. 205 equipped trucks (K30) retained the 10 spline coupler through '84.

To run a 27 spline 205 behind a 32 spline 465, you would need a new input shaft, input bearing, machine the case for the larger bearing and get an adapter to convert the case to round pattern. It would be expensive. Or you could get a later model round pattern 205, but those are expensive too.

By far, the cheapest and easiest solution is to run what you have. The 208 isn't that bad, just don't bash it on rocks, be sure to run a proper length front driveshaft, and run the stabilizer rod up to the bellhousing. Most people will never break a 208 with light to moderate wheeling.
 

Preston Tucker

Full Access Member
Joined
May 13, 2020
Posts
106
Reaction score
50
Location
Maine
First Name
Preston
Truck Year
1974
Truck Model
K20
Engine Size
350
By the way, you didnt get hurt on that deal. Just the bellhousing is worth more than that. Did you get the hydro pedal setup with it?
What you see there is what i got in the deal i do have a hydro setup for it out of a 2wd 87 c30 1 ton we had hanging around. I bought this unit becaue i was like a full unit i can just swap out my case! Then i relazed about a day later that the housing is different like you said race track vs. rounded. But yeah! Still made out on the deal i think, i need a stick right now and its stuck in gear without it in it. I hear it can be a slight pain to pop it in neutral to get the stick in it:banghead:
Any tips there?
 

Preston Tucker

Full Access Member
Joined
May 13, 2020
Posts
106
Reaction score
50
Location
Maine
First Name
Preston
Truck Year
1974
Truck Model
K20
Engine Size
350
To me, the 205 would always be the better option, but i dont think the length will be the same, as far as your driveshafts working. I think you could make the 205 work with the right adapter and coupler that mates the shafts. That 74 205 will use the “racetrack” bolt pattern so you will need the adapter like in my picture. The newer 465’s, i think, are 32 spline iirc,(older are 10 spline), and the 205 mated to the 350 should be 27 spline, i think. So with a 27-32 spline coupler and a racetrack pattern adapter you should be able to make it work, i think:).
Can you buy those adapters new? I think i have seen them before for like 200 but i am not sure if thats right or not. Thank you for the info, i am splitting my tranny right now to count the splines so i can find out exactly what i need to get the job done.
 

Preston Tucker

Full Access Member
Joined
May 13, 2020
Posts
106
Reaction score
50
Location
Maine
First Name
Preston
Truck Year
1974
Truck Model
K20
Engine Size
350
To me, the 205 would always be the better option, but i dont think the length will be the same, as far as your driveshafts working. I think you could make the 205 work with the right adapter and coupler that mates the shafts. That 74 205 will use the “racetrack” bolt pattern so you will need the adapter like in my picture. The newer 465’s, i think, are 32 spline iirc,(older are 10 spline), and the 205 mated to the 350 should be 27 spline, i think. So with a 27-32 spline coupler and a racetrack pattern adapter you should be able to make it work, i think:).
Are those adapters 27-32 splines actually manufactured of would that have to be custom made by a local machine shop? A link would be super helpful here if anybody know where i can get one!
 

K201979

Full Access Member
Joined
Oct 22, 2018
Posts
879
Reaction score
863
Location
Winona, missouri
First Name
Hippie
Truck Year
1979
Truck Model
K20
Engine Size
350ci
What you see there is what i got in the deal i do have a hydro setup for it out of a 2wd 87 c30 1 ton we had hanging around. I bought this unit becaue i was like a full unit i can just swap out my case! Then i relazed about a day later that the housing is different like you said race track vs. rounded. But yeah! Still made out on the deal i think, i need a stick right now and its stuck in gear without it in it. I hear it can be a slight pain to pop it in neutral to get the stick in it:banghead:
Any tips there?
Google and utube. I watched a guy named geb built. He was a member here at one point. His videos on the 465 may help. Otherwise, its gotta be out there, someone has dealt with it.
 

K201979

Full Access Member
Joined
Oct 22, 2018
Posts
879
Reaction score
863
Location
Winona, missouri
First Name
Hippie
Truck Year
1979
Truck Model
K20
Engine Size
350ci
Can you buy those adapters new? I think i have seen them before for like 200 but i am not sure if thats right or not. Thank you for the info, i am splitting my tranny right now to count the splines so i can find out exactly what i need to get the job done.
You can buy them new, but they are pricey. They are out there used too, but not much cheaper. Mine had both bolts broken off in it when i got it so i did try to source one, but with the prices, i just fought with mine.
 

K201979

Full Access Member
Joined
Oct 22, 2018
Posts
879
Reaction score
863
Location
Winona, missouri
First Name
Hippie
Truck Year
1979
Truck Model
K20
Engine Size
350ci
Are those adapters 27-32 splines actually manufactured of would that have to be custom made by a local machine shop? A link would be super helpful here if anybody know where i can get one!
Before i wrote that other post about having the right adapter, i googled it. I cant remember what i searched, but i saw something about 27-32 spline adapter. Ill see if i can find it.
 

K201979

Full Access Member
Joined
Oct 22, 2018
Posts
879
Reaction score
863
Location
Winona, missouri
First Name
Hippie
Truck Year
1979
Truck Model
K20
Engine Size
350ci
I searched 27-32 spline coupler.

You must be registered for see images attach
 

Preston Tucker

Full Access Member
Joined
May 13, 2020
Posts
106
Reaction score
50
Location
Maine
First Name
Preston
Truck Year
1974
Truck Model
K20
Engine Size
350
They went to 32 spline and no coupler shaft in '81, but only the 208 equipped trucks. 205 equipped trucks (K30) retained the 10 spline coupler through '84.

To run a 27 spline 205 behind a 32 spline 465, you would need a new input shaft, input bearing, machine the case for the larger bearing and get an adapter to convert the case to round pattern. It would be expensive. Or you could get a later model round pattern 205, but those are expensive too.

By far, the cheapest and easiest solution is to run what you have. The 208 isn't that bad, just don't bash it on rocks, be sure to run a proper length front driveshaft, and run the stabilizer rod up to the bellhousing. Most people will never break a 208 with light to moderate wheeling.
Well i have an issue there as i just found out when i split is, the 208 adapter to the case has an ear cracked right off of it, so thats out.
 
Last edited:

K201979

Full Access Member
Joined
Oct 22, 2018
Posts
879
Reaction score
863
Location
Winona, missouri
First Name
Hippie
Truck Year
1979
Truck Model
K20
Engine Size
350ci
Well i have an issue there as i just found out when i split is, the 208 adapter to the case has an ear cracked right off of it, so thats out.
I dont know what to tell you on that one. I guess maybe decide which direction you would ultimately rather go, and find the cheapest way to get there, and decide if that is possible. Maybe keep the hydro bell, sell the rest and find a 465 mated to the transfer case you want? If it was me, id sell the whole works and find a mechanical clutch bell, trans, transfer all mated already. Or a parts truck with one, but im old school.
 

Forum statistics

Threads
44,169
Posts
950,808
Members
36,286
Latest member
goodwrenchca
Top