what is the easiest way to swap an LS motor into a K10?

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.

Mattchu60

Full Access Member
Joined
Jul 25, 2012
Posts
197
Reaction score
10
Location
Iowa
First Name
Matt
Truck Year
1987
Truck Model
k10
Engine Size
350
I have an 1987 K10 with TBI 350 which is pretty worn out. I was planning on swapping in a crate 350, but I read so much good about the LS swap.

I have read a lot about the swap, but I get really lost in all the wiring. I dont know much about wiring a vechicle and dont want to lose my trucks functionality (a/c, cruise, etc).

I am pretty confident I could get the engine and a 4L60E swapped into the truck, but I would be totally lost trying to actually get it running and mated up with the trucks systems.

Is there a company out there that sells a total kit for wiring and ECM to run everything that makes it dummy-proof? I want plug and play if possible.

Also - I read conflicting posts on wether the oil pan on an LS engine will clear the front axle on a K10. I have no lift on this truck - will i have an issue?
 

87lsxgmc

Member
Joined
Oct 31, 2013
Posts
37
Reaction score
1
Location
buffalo
First Name
Paul
Truck Year
1987
Truck Model
2500
Engine Size
5.3
if your worried about wiring, and tune and all that stuff, when i swapped a ls1 into my camaro, i did a carb conversion. 6010 msd box for ls engines are real easy to wire up, mostly plug and play. hook up to a lap top to set the timing. for your ac, youl have to adapt the old lines to the new compressor. ill be trying to figure out a way to do that on my truck this summer. not sure about cruise or the oil pan issues.good luck!
 

MrMarty51

Full Access Member
Joined
Oct 25, 2012
Posts
7,794
Reaction score
10,022
Location
Eastern Montana
First Name
Martin
Truck Year
1978
Truck Model
K20
Engine Size
400
:popcorn::popcorn:I`m a watching and listening:popcorn::popcorn:
 

87lsxgmc

Member
Joined
Oct 31, 2013
Posts
37
Reaction score
1
Location
buffalo
First Name
Paul
Truck Year
1987
Truck Model
2500
Engine Size
5.3
im about to do a 5.3 conversion on my 87. im fixed on going injected since i have a donor truck with everything i need, but to run a carb is just too damn easy. anyone whose been around carbs long enough knows you can dial them right in. if i didnt tell you my camaro was carbd you would think its injected. excellent throttle response. i had all my friends fooled that it was injected till i popped the hood.
 

oneluckypops

Full Access Member
Joined
Feb 6, 2011
Posts
2,210
Reaction score
91
Location
Sedalia, Mo.
First Name
Luke
Truck Year
85
Truck Model
K30 SRW
Engine Size
5.7 Fuel injected Vortec/ 4L80E
I have an 1987 K10 with TBI 350 which is pretty worn out. I was planning on swapping in a crate 350, but I read so much good about the LS swap.

I have read a lot about the swap, but I get really lost in all the wiring. I dont know much about wiring a vechicle and dont want to lose my trucks functionality (a/c, cruise, etc).

I am pretty confident I could get the engine and a 4L60E swapped into the truck, but I would be totally lost trying to actually get it running and mated up with the trucks systems.

Is there a company out there that sells a total kit for wiring and ECM to run everything that makes it dummy-proof? I want plug and play if possible.

Also - I read conflicting posts on wether the oil pan on an LS engine will clear the front axle on a K10. I have no lift on this truck - will i have an issue?

I can help you with the Wiring. I do wiring harness modifications for vortec swaps. I could also build you a custom harness that would allow you to mount the computer and the fuse box anywhere you should choose. Turn around time is definitely faster and cheaper with using a stock harness and modifying it for your application.

PCM is not all that difficult, you will need to fill out a tune sheet telling the tuner what you are doing and what you want removed from the PCM memory, Most of the tuners are more then willing to help if you have questions on what you need and don't need.

A/C is pretty straight forward once you find a place to make your hoses, O'reillys does mine. But there are other sources out there as well.

Fuel system is probably the most difficult, but honestly it is not all that hard.


Let me know if you would like for me to help you or not. PM me for the fastest responses.
 

Mattchu60

Full Access Member
Joined
Jul 25, 2012
Posts
197
Reaction score
10
Location
Iowa
First Name
Matt
Truck Year
1987
Truck Model
k10
Engine Size
350
Thanks for the info guys. OneLuckyPops - I live in north IA and there are no tuners around here, probably closest is around 125 miles away, I assume there are guys that do it through mail order. Are your harnesses all tagged so its dummy-proof?

What year/model truck should I look for an LS and trans swap? I would want to keep the cable driven throttle I think - I want to retain Cruise Control - would my factory system work or would something need to be rigged up?

Lastly -anyone have an idea if the oil plan will clear?
 

Jims86

Full Access Member
Joined
Aug 3, 2010
Posts
5,492
Reaction score
135
Location
Patterson,Ca
First Name
Jim
Truck Year
1986
Truck Model
K10 Suburban Silverado
Engine Size
5.7 TBI
Motor? You going electric?
 

oneluckypops

Full Access Member
Joined
Feb 6, 2011
Posts
2,210
Reaction score
91
Location
Sedalia, Mo.
First Name
Luke
Truck Year
85
Truck Model
K30 SRW
Engine Size
5.7 Fuel injected Vortec/ 4L80E
Thanks for the info guys. OneLuckyPops - I live in north IA and there are no tuners around here, probably closest is around 125 miles away, I assume there are guys that do it through mail order. Are your harnesses all tagged so its dummy-proof?

What year/model truck should I look for an LS and trans swap? I would want to keep the cable driven throttle I think - I want to retain Cruise Control - would my factory system work or would something need to be rigged up?

Lastly -anyone have an idea if the oil plan will clear?

Yes you would probably be best with a mail order tune.
Yes when I do a harness it is "dummy proof" all connectors, fuses, Relays, Grounds, Ignition, and Power wires are labeled. The labels will even tell you where the connection needs to be made... I also include my e-mail, and phone number so that you may call or text me with any questions you may have during your installation.

As far as cruise control is concerned. Yes you can use your factory cruise set up, BUT IMHO I would consider going with the newer style cruise. To me it is much more reliable then the vacuum operated.
 

scottsdale77

Junior Member
Joined
Jan 11, 2014
Posts
1
Reaction score
0
Location
Georgia
First Name
Chris
Truck Year
1977
Truck Model
K10
Engine Size
small block 350
i have a 1977 4x4 k10 scottsdale with a 4in suspension lift and a 3in body lift. With a rebuilt 350 and transmission. I was wanting to put a Ls1 with transmission in my tuck, i was wondering if it was worth my time and money to do it.
 

87lsxgmc

Member
Joined
Oct 31, 2013
Posts
37
Reaction score
1
Location
buffalo
First Name
Paul
Truck Year
1987
Truck Model
2500
Engine Size
5.3
what do you use the truck for? a th350 is hands down stronger than a stock 4l60e, you could split it up and just drop the motor in, and get an adapter plate for your converter and run the th350. for a little bit more hp is it worth it, thats up to you and your goals with the truck, imo the ls base engines are a better platform to start with, get a mild cam kit in any stock bottom end your easlily going to make 450hp good luck!
 

Joshua8336

Full Access Member
Joined
Dec 11, 2011
Posts
298
Reaction score
0
Location
Dirty South AL
First Name
Joshua
Truck Year
1985
Truck Model
c10
Engine Size
4.8
I have an 1987 K10 with TBI 350 which is pretty worn out. I was planning on swapping in a crate 350, but I read so much good about the LS swap.

I have read a lot about the swap, but I get really lost in all the wiring. I dont know much about wiring a vechicle and dont want to lose my trucks functionality (a/c, cruise, etc).

I am pretty confident I could get the engine and a 4L60E swapped into the truck, but I would be totally lost trying to actually get it running and mated up with the trucks systems.

Is there a company out there that sells a total kit for wiring and ECM to run everything that makes it dummy-proof? I want plug and play if possible.

Also - I read conflicting posts on wether the oil pan on an LS engine will clear the front axle on a K10. I have no lift on this truck - will i have an issue?

painless makes a kit. depending on the year and if I can find some pinouts you can send me your engine harnesses and I can mate them together. PM if interested
 

Matthew Scott

Junior Member
Joined
Jun 11, 2018
Posts
2
Reaction score
5
Location
prior lake, mn
First Name
Matthew
Truck Year
1975
Truck Model
510/20
Engine Size
350
I can get an LS 5.3 out of a Silverado with 104K miles for $400 and it has all the wiring. Should this be an easy swap? Does anyone make a list of the small parts needed?
 

smurfasaur

Full Access Member
Joined
Aug 23, 2017
Posts
133
Reaction score
44
Location
Central WA
First Name
Austin
Truck Year
1979
Truck Model
K20
Engine Size
289
Thanks for the info guys. OneLuckyPops - I live in north IA and there are no tuners around here, probably closest is around 125 miles away, I assume there are guys that do it through mail order. Are your harnesses all tagged so its dummy-proof?

What year/model truck should I look for an LS and trans swap? I would want to keep the cable driven throttle I think - I want to retain Cruise Control - would my factory system work or would something need to be rigged up?

Lastly -anyone have an idea if the oil plan will clear?

Tons of people do mail- order tuning if you’re not near a local tuner. I had BlackBear performance do a tune for my 5.3 since I did a cam swap and headers, etc.

Harness isn’t scary at all. Only 2-3 sensors use the same plug if I remember right so it’s pretty foolproof if you buy a premade harness.

Cable throttle body was from 99-02 or 03 I believe and IMO is easiest like you say. Drive by wire isn’t rocket surgery either though and makes hooking up cruise control really slick.

Oil pan clears just fine depending on your engine position and motor mounts. I used dirty dingo slider mounts to get my engine/trans as close to stock as possible and I had to put about 0.25” spacers in between the block and mounts in order to have clearance on the engine crossmember. I believe there are some folks that have used tejas mounts on 4x4s with no spacers though. Definitely check out Tejas, and the LS swap squarebody Facebook group. Tons of help.


Sent from my iPhone using Tapatalk
 

Camar068

Supporting Member
Supporting Member
Joined
Feb 5, 2014
Posts
4,293
Reaction score
3,339
Location
Kentucky
First Name
David
Truck Year
1986
Truck Model
K10/LM7 5.3/4L60e/np208/3.73/32"
Engine Size
10 yrs Air Force
I had to put about 0.25” spacers in between the block and mounts in order to have clearance on the engine crossmember.

I got lucky with the dirty dingo's and had a 1/4" between the two....and there was a vacuum hose (not being used) sitting in that spot so it's jammed in there lol. Thought about the washers, will do that if needed.

Mathew Scott, you'll need a sender from an 87 to add the fuel pump to. Could probably make the older style work, not sure though. This is assuming your using your existing saddle tank.
 

smurfasaur

Full Access Member
Joined
Aug 23, 2017
Posts
133
Reaction score
44
Location
Central WA
First Name
Austin
Truck Year
1979
Truck Model
K20
Engine Size
289
I got lucky with the dirty dingo's and had a 1/4" between the two....and there was a vacuum hose (not being used) sitting in that spot so it's jammed in there lol. Thought about the washers, will do that if needed.


Nice, yeah I’ve heard mixed things about having to notch the crossmember or do spacers. If I had to do it again I would probably just fab a new crossmember.


Sent from my iPhone using Tapatalk
 

Forum statistics

Threads
44,173
Posts
950,869
Members
36,289
Latest member
HT2abbottrl
Top