72 K-10 LS1 swap

[azsmokey]

Hello everyone,

I am new to this message board, but in my brief time, have seen a lot of nice vehicles and a lot of passion for the 67-72 truck body style. It is my personal favorite and had always wanted to build one.

It is my good fortune to have a grandfather-in-law that has a 1972 K-10, which he has had since new, who has decided it is time to do a restoration on the truck. I am not familiar with the underpinnings of this model at all and most of my knowledge comes from working on older Chevy small blocks and my late 98 LS1 powered Camaro.

Our plans include the installation of an LS series engine and late model transmission, 4-6 inch lift, new wheels and tires, paint, front and rear diffs, brakes, interior... He really wants to overhaul the truck and I am more than happy to embark on this project with him! I completed a small block swap into an 83 S-10 a few years ago with a motor mount kit and other accessories, but that is the sum total of my experience with swapping engines. This truck already has a small block V-8 underhood and not the V-6, so I believe the swap should be straight forward.

I have spent time researching the swap and have found a number of 2WD swaps but have yet to find an LS series engine and 4L series GM tranny in a 4WD 67-72. If there is anyone out there that has completed the swap into that vehicle type, I would love to pick your brains and hear some of your experiences.

-Are there any major issues with late model LS series engines ad transmissions fitting into that vehicle?
-Any issues with hooking up the transfer case? Should I replace the case with a different unit for ease of the swap/durability?
-He stated he would like to swap in Dana 60's, both front and rear and use disc brakes. Issues there?
-I know there are companies that make motor mount plates for the LS1 swap, but are there any transmission mount issues? Is a new crossmember needed? I am a fairly competent mechanic and have other friends that are good welders/fabricators, additionally there is no time frame for completion so we are going to have fun and take our time.
-Are there any good web sites documenting the swap process with the LS series engine?
-If we keep the existing diffs, is there a company that makes a complete disc brake swap, both front and rear?
-I have a list of other questions, but I will stop for now as this is my first post.

I look forward to hearing from other members about their experiences and look forward to working on this truck! Please share any information that you think would be useful in our situation. I hope you all have a great New Year!

[Mudder]

I am moving this over to the 4x4 area so that those guys there will be able to answer most of your questions best. You can also go to the welcome area and intrduce yourself there. It is good to have you here and I am sure if you look deep enough here you will find a mountain of useful information. I try to keep the 4x4 chassis stuff seperate from the 2 wheel drive chassis stuff.

[Zoomad75]

Welcome, Monkey! You got a pretty ambitious project planned there. As far as anybody else installing a gen 3 Small block into a 4x4 67-72. I know of two on these boards. One is a K5 Blazer running a 6.0L with a blower. He posted a video of it some time ago and it was killer sounding. The other I think was the guy converting the 4x4 to 4 links and air bags for soft riding. I haven't seen much posting by either, but a quick search should turn somehting up.

As far as the mechanics of the swap, it's pretty straight forward as a couple of companies make adapter brackets to relocate the engine mounts to the traditional small block location. You then use the exisiting engine cross member to bolt it up. It will depend on what accessory drive you plan on running to see if it clears the stock x-memeber though. The trans used would either be a 4l60 or 4L80 right? No problem there, you just need a passenger side drop t-case. A np241 from a later solid axle truck (87-91) might be the one to look for. You will just need to find the correct trans/t-case adapter. Your existing case (np205 or Dana) won't bolt right up to the newer trans.

You've got plenty of options for axles. What's the direction for the truck? Will it get used off road? If he wants beef in the axle department I'd go for a 14bolt full floater out back and if you can find one, a D60 up front. I don't see the need of trying to find a D60 rear axle as they are hard to come by and still don't match the strength of the 14 bolt. 14 bolts are MUCH cheaper to aquire than any D60. 14b rear disk kits are plentiful on the web. If when you start shopping for the front D60 and find the pricing out of the park, you could consider an 8 lug D44 from a later 73-77 3/4 ton or a 8 lug 10 bolt from 78-91. Both are a bolt in, come with disc brakes and while they aren't as bulletproof as a D60, if you keep the tire size around 35/36" the will survive.

LS1.com has a pretty good swap section. You can use the guys on this site that have swapped Gen 3's into 2wd's as a reference too. Even though they may be 2wd's the engine mounting is the same. Only difference is you will have some extra stuff hanging from the back of the trans.

Pleanty of info here once you dig for it.

[boostat4500]

Hello. I may be able to help a little here. My burb was a bone stock 1/2 ton 4-speed when I got it. It now has a LQ9(6.0L)/4L80E/NP246 drivetrain with a rear 14 bolt and front Ford Dana 44, disc brakes front and rear. The lift is a
6" with both axles moved back 1" to give you an idea there. Tires are 38x15.50r16. For the sake of not writing a novel in one post, shoot me some specific questions and I'll do the best I can to help. Here's a few pics to show the drivetrain.

[Yukon Jack]

Welcome to the board - looks like some great info has been posted to your questions. Keep us posted on your progress on this project.

[67GMC3/4]

nice burb, looking to do similar how did you do the wiring ?

[Mr. 250r]

Mounts - http://dirtydingo.com/store/
Disc Brakes - http://diy4x.com/ http://www.offroaddesign.com/catalog.htm
Transfer Case np241 passenger side drop to match chevy axles like Zoomad said
Those companies are off the top of my head there are many more for mounts and disc brakes but i just couldn't remember them all

But it all comes down to is this truck going to be abused or not then you could save some money on a D60 or a D44/10 bolt, i ran a 10 bolt with 38.5s street and mud/hills etc and it was fine up until i tried yanking out a truck multiple times i broke the axle so i put in a D60 which i got cheap