1985 GMC 4x4 LS Motor Swap, tons of pics!

[bohmankid]

Here is my current project I would like to share with you. I bought this truck in July 2011.
The short story: I was pulling parts off a part-out Mustang for my Foxbody when I saw this truck sitting across the lot. I said to the man selling me the Mustang parts that I liked that truck. He said it's for sale for $1800 as it sits, or $3000 after they figure out what is wrong with it and fix it. I told him I'll take it as is, non-running and snapped a picture of it:


I had a friend tow it home for me. The truck is an 85 but it has a 350 TBI motor out of an 87 Blazer and the rest of the drivetrain is out of a 91 as well as the single front accessory belt. I put gas straight into the throttle body and the truck started and ran fine until I stopped pouring gas down it's throat. So it was a gas problem. Simple.

I pulled the bed off.


I also pulled out the gas tanks. Both were rusted through, but that wasn't the no gas problem.

[bohmankid]

The frame had surface rust, I was surprised by how good of shape this truck was in. I pulled up the carfax and it has been in Utah its entire life. Utah salt is not good to these vehicles. I am also the 3rd owner.

[bohmankid]

The reason why this truck didn't run when I bought it is because a fuel line inside the tank was split! Here is the tiny $0.99 cent problem!


I sanded down the frame and sprayed it with undercoating. I also painted the driveline and had fun with high heat paint.

[bohmankid]

Just a few more random pics...

[bohmankid]

And pics of the motor that it came with...

[bohmankid]

A few months after I bought the truck, a buddy of mine left his Mustang in neutral and it rolled down the driveway and into my truck that happened to be parked across the street..




I took the truck to a body guy I know and he got it all fixed up. Also cut out some rust on the other door and repainted both doors while it was in the shop. I put on a new exhaust with long tube headers after the paint was done, and went out shooting. I snapped a picture on the dirt road. You can see the new tips in the picture below.

[bohmankid]

I purchased new wheels for the truck and didn't like them. So I sold them for a profit the very next day, lol. I thought it looked like a hotwheel. I think I'll stick with the 16 inch wheels.




I also bought a cowl hood and took it to the same guy that painted my doors.

[bohmankid]

The radiator crapped out on me so I replaced it with a Champion radiator with dual electric fans. I got rid of that clutch fan in a hurry.

[bohmankid]

I tinted the windows, and everything was running smoothly!..


Until my tire blew out..


For some reason, 3 studs had to be replaced after the tire blew. This is just a picture of me taking off the rotor. You have to take apart the hub to replace the studs.


I bought new wheels and tires. Now things are looking up.

[bohmankid]

September 2012: I redid the exhaust again, probably because I was bored. I want to do something crazy to this truck but I didn't know what.

[bohmankid]

Now this is where things get a little crazy. I decided to go with a motor swap. Once again, probably because I was bored. I researched LT1 swaps, LS1 swaps, Cummins swaps, 6.0 and 5.3 swaps.
I came across a nice 5.3 with wiring harness and almost all accessories and I went and picked it up.






I hate the way these manifolds look though.

[bohmankid]

Looks good in there. This motor has 80,000 miles on it. In the clean up phase.


The oil looks fresh as well

[bohmankid]

I pulled the radiator support off the truck and got ready to pull the old motor out. I have never done this before, so all of this is new to me. Everything I know is from research and forums, lol. Hopefully I don't screw up.


I went with the Dirty Dingo adjustable motor mounts.


I cleaned up the engine bay and undercoated most of it.




I cleaned up the motor and painted it as well. Just waiting on a few parts to come in.

[bohmankid]

I'm going to be using my TH400 transmission so I had to order a flexplate spacer and longer bolts to hook this Gen III motor up to the old school trans.




The motor dropped in pretty good. It looks tiny in there.

[bohmankid]

I put the truck back together and all I need to do now is the fuel system, exhaust, and wiring


I am NOT looking forward to the wiring.

[bohmankid]

Welp, I purchased some stainless steel long tube headers and they fit pretty good. They are for a 2010-2012 Camaro 6.2-liter LS3. I got them because they looked like they tucked in pretty good and the collectors came out straight.


The passenger side fits snug. But I think I can get away with it.


The drivers side is great.


Both collectors dip a little low as you can see in the two pictures below. So I will need to cut those off and reposition them.




These next two pictures show the only modification I had to make. I used a flap disc to grind down the bottom of the frame only. I left the top alone. These pictures are viewing from the ground.
Drivers side:

Passenger side:

[bohmankid]

And now my thread is up to date. I still need to hook up the wiring harness, fuel system, and finish exhaust. Phew! I am $1900 into this swap so far..

[Greenlee]

Nice truck. I like the paint scheme.
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[bohmankid]

Thanks! I like it too. It's got a new school/old school look. The gray is stock, but the blue has been upgraded to an 'Ultra Blue' color.
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[y5mgisi]

Cool truck man! Good job so far!

[bohmankid]

Thanks y5! Believe it or not, it was your suburban build thread on CK5 that made me want to do this 5.3 swap!

[OutlawDrifter]

nice looking pickup, good progress so far!

[y5mgisi]

Haha! Thats awesome! Glad i could persuade you! I LOVE the way my 5.3 runs! I want to put one in the rest of my trucks now! The swap itself is pretty easy and kinda fun. I ended up actually enjoying the wiring aspect... The lame thing is i STILL havent gotten my computer tuned with a 5.3 tune... Its still running a VSS-less 5.7 tune. I Can not wait until i get a good "performance" tune on it and one that reads the VSS as well as park neutral. So, despite that fact that it runs very nice and near perfect all the time, its going to be alot better when its all dialed in.

[FrostyTheSnowman]

Nice to see another fellow Utahn on the boards!

I dig the truck, very clean for a truck that's lived its entire life in Utah for sure.

Love the Camaro headers too.

[bohmankid]

Originally Posted by y5mgisi

Haha! Thats awesome! Glad i could persuade you! I LOVE the way my 5.3 runs! I want to put one in the rest of my trucks now! The swap itself is pretty easy and kinda fun. I ended up actually enjoying the wiring aspect... The lame thing is i STILL havent gotten my computer tuned with a 5.3 tune... Its still running a VSS-less 5.7 tune. I Can not wait until i get a good "performance" tune on it and one that reads the VSS as well as park neutral. So, despite that fact that it runs very nice and near perfect all the time, its going to be alot better when its all dialed in.

Yes, definitely. I'm taking my truck to a local performance shop I like to get it dyno tuned once it's ready.

Originally Posted by FrostyTheSnowman

Nice to see another fellow Utahn on the boards!

I dig the truck, very clean for a truck that's lived its entire life in Utah for sure.

Love the Camaro headers too.

Definitely. It's awesome when you can meet local people on forums and get some hookups on parts and a close helping hand if willing! Forums are awesome!
I was very happy when the headers went on smoothly, Thanks.