Re: post your 67-72 4x4
 

Man I’ve loved that truck since you first posted it! Great looking piece of iron!

Re: post your 67-72 4x4
 

Very nice truck , My suggestions: Drive it , Enjoy it :metal:

Re: post your 67-72 4x4
 

Thanks everyone! And I have been driving it quite a bit, but I am wrestling with which way to go on upgrading the drivetrain.
My wife wants to drive the red ‘70 regularly and the old Holley has to go for starters.
A big block ain’t the most efficient set up and prone to oil leaks.
I have converted my wife’s ‘41 ford pickup (350/350) to efi with a Holley sniper and it sure runs good and starts all year with no drama.
So considering a sniper efi upgrade on the big block, but long term I am also considering & researching an LS/overdrive conversion instead.
The LS Seems a little overwhelming (and expensive) with the Np205 thrown into the mix, but once completed should be trouble & leak free.
Any thoughts from members with experience on these LS Np205 4x4
conversions would be much appreciated!

Re: post your 67-72 4x4
 

I’m hoarding parts for my ls swap now. My plan is to keep the 465/205 in there place and mount the 6.0 wherever it needs to be to keep the stock driveshafts in place. I know that doesn’t exactly help with the od transmission in this case. For my 3100 I’ve got a turbo 400/205. I’m gonna 6.0 or even 8.1 swap that one with a 4l80E and the turbo 400 spec 205.

Re: post your 67-72 4x4
 

I've got the 6L90 with my NP205 (kept the stock trans crossmember and location but fabricated a few mods). Happy to share any lessons learned as it's a bit harder to find LS swap info with a transfer case mixed in on the board.
I'm wiring my LS engine as I write this...prepare for a lot of work with an LS swap but I get more and more excited each day I make progress!

Re: post your 67-72 4x4
 

I’ve got a 4x4 6L90 that came with my 6.0, I’ve thought about that route but man it’s pricy getting the 205 behind it. It’ll be nice when you get it all done. I’ve got an 18 Sierra 2500 with that tranny and it’s quite nice to drive. The 6L80 in my Camaro is every bit as good drivability wise. The low first and second gears In both of them get you out of the hole pretty well.

Re: post your 67-72 4x4
 

That seems like a reasonable plan.
Questions;
1.crate LS or boneyard LS?
2. Turbo 400 spec NP205? Early GM NP205’s are not all the same ?
Thanks in advance!

Re: post your 67-72 4x4
 

Negatory on the early 205’s. I believe save the adaptor housings and the coupler setups, the (84 and earlier) turbo 350 and sm465 205s are the same. ie. you can take a 465 205 and swap the adaptor housing and the coupler between the tranny output and the 205 input and convert it into a 350 205. The turbo 400 205 has a larger input shaft and bearing that requires machine work on the early 350/465 205 case to work. Because a 4L80E is basically a turbo 400 with overdrive it’s not very difficult to mount a turbo 400 205 behind a 4L80E. Does that make sense? Basically the 69-84 gm TH350/SM465 205’s are all the small diameter input shaft cases. These will all be referred to as the figure 8 or race track case because of the way the tranny adaptor bolts up. Somewhere in the mid 70’s Gm introduced a 400 205 that is the same racetrack/figure 8 pattern But had the needed bigger input bearing. In 85 they switched to what is called the round 205 (again for the pattern that the tranny adaptor bolts to it) all round 205’s will interchange between SM465 and TH400 with the correct coupler and adaptor housings. The round 205’s all use a longer 32 spline input shaft and are stronger in that area than the older 205’s. If you can find an 85-91 square body K30, you’ll get this case regardless of the transmission it’s got in it. Hope that helps with the 205’s some. There are other changes to the 205 thru the years but these are some of the more major ones.
As for my 6.0 it’s out of a totaled 2009 Silverado.

Re: post your 67-72 4x4
 

thanks! Sorry no SPID with truck...

Re: post your 67-72 4x4
 

Thanks so much for clarifying. I have a lot to learn!
So if I am following you correctly since I am currently running a t350 I can assume that I likely have a smaller diameter input shaft version of the np205.
Is the 700R4 the best OD auto for this NP? Or does one of the the newer electronic versions (other than the 4L80E) mate up well?
Thanks again!!:metal:

Re: post your 67-72 4x4
 

Hey Rowdy11...Had to read through all of your build thread before responding and now have a full page of new questions! Won’t ask them all now, but will definitely keep your offer in mind!
Gotta admit your experience scares me a little as I do not want to (or need to) dismantle my truck. That band saw action would be a challenge with the np205 in the truck.
I am hoping to keep the NP in place and “slide in” an OD Tranny and LS motor.
That’s sounding a little simplistic after reading your thread.
Maybe the Sniper add to the existing 402BB is more in the cards.
Sure appreciate all of the comments and offers for assistance !!!
6L90e six speed sounds awesome! Extra challenges with that set-up I am guessing?

Re: post your 67-72 4x4
 

The 700r4 will work with the case you’ve got. Several people on here have done that conversion. The th350 205 is the actually the best one to have for that conversion.

Re: post your 67-72 4x4
 

The 700r4 will need a new adapter type output shaft to mate to a 205. Not hard to do but make sure you get a 700r4 that is 1986 or newer as it is a stronger unit. The older ones should be avoided if possible. You can read up on it. I rebuilt my 700r4 with all B-M internals etc and was easy to install the new shaft at that point.

Re: post your 67-72 4x4
 

Here's my '68 K10 I brought back from Colorado the last weekend of June. Near as I can tell it's the original 250, SM465, and T221 setup. The frame matches the VIN as well. It still has the closed knuckle D44 and I believe the rear axle is a 12 bolt but I haven't got that far yet. I've rebuilt the carb, gapped the plugs (some had no gap), and corrected timing and it runs pretty good, though smokes a bit. It came with some odd bucket seat and I'm searching for a 67-68 bench seat to fix that issue. The cab needs some attention in the usual locations. The fenders are crinkled pretty good and the grille will need to be replaced as it got bent too. I was told it was an old farm truck and it shows, but the bed is from a newer model and in good condition for its age. The hubs are an interesting situation. The driver side has a full time cap and the passenger has a Warn hub. I wish I could find another one and get rid of the cap. All in all, I'm excited for this project. I've been looking for a K for a long time.

Re: post your 67-72 4x4
 

Heck yea! That’s a great looking ‘68. Other than the bed and the seat it looks to be pretty original. What are your plans for it? Welcome to the 67-72 K club!

Re: post your 67-72 4x4
 

Great score...Now the fun begins.....

Re: post your 67-72 4x4
 

The plan is to get it back to original look and feel as much as I possibly can. I'd like to keep the closed knuckle but understand parts are getting harder to come by, especially the hubs. Based on what I can see (no SPID) the paint is the 506 Medium Blue Poly and I'd like to keep it that way too.

Re: post your 67-72 4x4
 

Thanks JJ!

Re: post your 67-72 4x4
 

Haven't been on this site for a while. Here's my 69 original paint K10 that I put 3/4 ton axles under. Hopefully LS swapping it next year.

Re: post your 67-72 4x4
 

Awesome truck!!

Re: post your 67-72 4x4
 

@rowdy11

I wrote this back in 2009

MATING 4L60 TO NP205

Re: post your 67-72 4x4
 

I like the color combo.

Re: post your 67-72 4x4
 

You bet! Happy to answer any questions and promise not to hide either the good or the bad...it's been a big learning experience for sure!

Re: post your 67-72 4x4
 

Very nice write up!

Re: post your 67-72 4x4
 

To the top

Re: post your 67-72 4x4
 

Last weekend.

Re: post your 67-72 4x4
 

Heck yea!!! Looks like a good time!

Re: post your 67-72 4x4
 

My work in progress. From C20 to K10.

Re: post your 67-72 4x4
 

Nice work

Re: post your 67-72 4x4
 

My Dad's truck

Re: post your 67-72 4x4
 

My K10 before I took it apart.

Re: post your 67-72 4x4
 

Haven't posted on this thread since it was painted. All painted, got the bed LineX done and this week it goes in for some clear bra.

Re: post your 67-72 4x4
 

That sure is a purdy truck. I like the Monte Carlo too.

Re: post your 67-72 4x4
 

Thank you, the Monte Carlo is a 71' and nice road car.

Re: post your 67-72 4x4
 

Couldn't be better

What a '70s time capsule. I had a '72 blazer with the chrome smoothies and other accessories. Dual auxiliary tanks was one of the upfits. Looks good here and looks great now!

Re: post your 67-72 4x4
 

Those wheels are 16.5 x 8.

Re: post your 67-72 4x4
 

1970 c10 327 sm465

Re: post your 67-72 4x4
 

Awesome truck Sanddunecoon!