The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 02-12-2021, 02:28 PM   #1
tinman_local2
Registered User
 
Join Date: Jul 2015
Location: Smithton, Mo.
Posts: 158
69 k20 rockwell to np205 swap

I swapped out the old t-221 for a np205. I didn't move the transmission cross member. It appears the distance from the front of the bell housing to the center of the motor mount is a little short. The mounting adapter on the 205 is 2 1/4" longer than on the 221. Are there any problems with moving the front cross member forward a couple inches. I'm down to bare frame so it won't be hard to do, just don't want to run into trouble later.
tinman_local2 is offline   Reply With Quote
Old 02-13-2021, 08:29 AM   #2
CUSTOM/10
Senior Member
 
CUSTOM/10's Avatar
 
Join Date: May 2003
Location: Sandown, NH
Posts: 2,833
Re: 69 k20 rockwell to np205 swap

I can't answer your question, but I can give you some info that might help you avert another issue. The t221 cross member is 1" shorter ( top to bottom ) than the np205 cross member. So if you use the t221 cross member with a np205 your t-case might be hitting the floor of your truck !

Gary
__________________
Gary
72 SWB 4x4

My 72 SWB Build
http://67-72chevytrucks.com/vboard/s...d.php?t=259859
CUSTOM/10 is offline   Reply With Quote
Old 02-13-2021, 05:28 PM   #3
gmc684x4
Registered User
 
Join Date: Jul 2012
Location: Whitehorse yukon
Posts: 1,218
Re: 69 k20 rockwell to np205 swap

I have done this swap several time I used the complete tranny transfer case and crossmember for the swap
Which transmission did you have sm420 or sm465 ?

The 465 np205 with matching crossmemeber
It will sit back further and need new holes
420 t221 vs 465 205 combo use different drive shaft length as well I can not say about the 465 t221 combo as I have not played with that setup
gmc684x4 is offline   Reply With Quote
Old 02-13-2021, 06:36 PM   #4
tinman_local2
Registered User
 
Join Date: Jul 2015
Location: Smithton, Mo.
Posts: 158
Re: 69 k20 rockwell to np205 swap

I've got the 465. I moved the front cross member forward. I think it will help with the transfer case interference with the cab leaving the original trans cross member where it is. Hopefully this isn't a mistake.
tinman_local2 is offline   Reply With Quote
Old 02-14-2021, 07:59 AM   #5
CUSTOM/10
Senior Member
 
CUSTOM/10's Avatar
 
Join Date: May 2003
Location: Sandown, NH
Posts: 2,833
Re: 69 k20 rockwell to np205 swap

If the t-case does hit the floor you can get a t/c lowering kit, it's basically some spacers and longer bolts.

Gary
__________________
Gary
72 SWB 4x4

My 72 SWB Build
http://67-72chevytrucks.com/vboard/s...d.php?t=259859
CUSTOM/10 is offline   Reply With Quote
Old 02-14-2021, 04:24 PM   #6
gmc684x4
Registered User
 
Join Date: Jul 2012
Location: Whitehorse yukon
Posts: 1,218
Re: 69 k20 rockwell to np205 swap

When swapping i kept motor in stock 4x4 location and used drive shafts from donar vehicle that I swapped tranny tcase from
Is your front shaft a double cardigan joint ?
Most of the diff is a 420 tranny is shorter then a 465

Moving the engine forward you will have to watch for clearance issues with the front diff pumpkin which is why the engine is in the back position
gmc684x4 is offline   Reply With Quote
Old 02-14-2021, 07:10 PM   #7
tinman_local2
Registered User
 
Join Date: Jul 2015
Location: Smithton, Mo.
Posts: 158
Re: 69 k20 rockwell to np205 swap

Quote:
Originally Posted by gmc684x4 View Post
When swapping i kept motor in stock 4x4 location and used drive shafts from donar vehicle that I swapped tranny tcase from
Is your front shaft a double cardigan joint ?
Most of the diff is a 420 tranny is shorter then a 465

Moving the engine forward you will have to watch for clearance issues with the front diff pumpkin which is why the engine is in the back position
The drive shaft is the double jointed one. I've got a 4" lift, so I don't foresee any clearance issues with the differential. I'll have to have the drive shaft lengthened. The rear will need shortened.
tinman_local2 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:15 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com