86 K10 5.3 swap

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Camar068

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K10/LM7 5.3/4L60e/np208/3.73/32"
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10 yrs Air Force
Getting close to purchasing one in the next few days hopefully. After a long conversation on the phone with the seller I asked if the fuse box comes with it. He said it's a PITA using the stock box and to go with a smaller box.

I haven't noticed this on the web and figured I'd check you all's thoughts. The pricing on the engines he has been selling seems a bit questionable to me. $850 top to bottom/front to back w/harness/computer and normally under 100K miles. I say questionable because on my budget spreadsheet I had $550 for one with 160K miles.

LOL serial number on fuse box? see where I'm going?

Opinions on the price and fuse box please. (Edited part) Aside from a compression test, what else should I test, if anything, before I buy it? I haven't searched for this part, if it's out there excuse my idiocy LOL.

Thanks Again Guys
 
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foamypirate

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850 for a complete 5.3L with accessories/harness/ECM doesn't seem too out of line, especially without a transmission included. I paid $1500 for my LQ9 6.0L, no trans, but had harness/ECM/accessories, but that also has a 6 month warranty, and video of the engine running before pulled from the wrecked truck.

As far as the engine goes, short of it being running in a wrecked vehicle, I'd pull a valve cover just to check things out, make sure they aren't crudded up, compression test for sure, and even just looking at the spark plugs to see their condition (should be a nice light tan color), can go a long way.
 

dougbert

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5.3L - 2002 Silverado, rebuilt top end, long tube headers
For doing your own harness and building a small fuse box (4 fuses) that works great, see www.lt1swap.com for all his reference data, instructions and pictures on how to do it all.

all free. All he charges is $75 to flash your ECU, he is one of several who does this full time now. But you don't need to use him. But did since I got a lot of info from his website

try http://www.car-part.com/ for look for an engine as well

I documented my harness rebuild and fuse box build in my 1984 build thread in my signature

dougbert
 
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Camar068

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Looked at the one below today. Talked him down to $900 for engine/tranny (top to bottom/front to back on the engine) and them pulling it. I noticed a lot of oil/dirt on the top front (roughly where the thermostat would be on a 350) and around the valve gaskets. What do ya'll think? This one can be started as it's still in the truck....and it's here in town.

What do ya'll think as a back up plan if the $850 engine doesn't pan out? The plan is to clean/paint it and drop it in....no internal work to it.

https://lexington.craigslist.org/pts/5481279017.html

It had 3 bolts replaced around 4 & 6 cyclinders exhaust. Maybe broken off inside. I'll check that if I decide to seriously look at buying it. actually you can see them in the pics if you CTRL mouse scroll in. Brass color in between 4 & 6.
 
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Camar068

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86 K10 5.3 swap prep

got a 5.3 and tranny yesterday (not the one above). Before we took it out, I fired it up and listened to it (no radiator). It ran fine. Didn't put in gear because I didnt think I was getting the trans.

Anyway, It dawned on me after we got home 3 hours later that trans fluid wasnt shooting out the disconnected coolant lines as it did on my 700r4 when I moved it a few feet w/o radiator in place. Is this a bad sign for the trans? It has fluid in it...well it leaked out the ass end when tilted.

Gave $1200 for both engine trans (2006 Silverado crewcab 114K miles)
 
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Camar068

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spoke with my transmission guy, he said it may be low on fluid or it has issues.
 

Camar068

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little busy today taking stuff off to get to the block to clean up. It's got some rust here and there. Have had a hard on since we picked it up Wednesday LOL. I'll be a lot better when I take of the pan to look at the crank #'s to verify that it's a 5.3 and not a 4.8. Mine didn't have a painted dot on either the 4.8/5.3 stamp on the rear.

picture.php


picture.php
 

foamypirate

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Off to a good start! If you have any questions about the swap, I can probably help out. Just about finished with my swap (only have exhaust left to do).
 

Camar068

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did you mount a 4l60E to a np208? Having a hard time understanding why folks go with the adapter from Advance adapters. Is it just for the vss signal to the computer? If so couldn't a Dakota Digital adapter be used and have both mechanical/vss signal?

I've read about it but it's been a while. I'll read up again when I'm not working on it today. I was sure I had this issue finished in my mind....only cable adapter needed.
 

foamypirate

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did you mount a 4l60E to a np208? Having a hard time understanding why folks go with the adapter from Advance adapters. Is it just for the vss signal to the computer? If so couldn't a Dakota Digital adapter be used and have both mechanical/vss signal?

I've read about it but it's been a while. I'll read up again when I'm not working on it today. I was sure I had this issue finished in my mind....only cable adapter needed.

Mine was a 2WD, but I've seen a few people add tone rings to the NP208 for a VSS output. If you are on Facebook, check out the following group:

LS Swapped Square Body GM Trucks ('73-'86 C/K & '87-'91 R/V)

They are dedicated to LS swaps in Squarebodies, and there are quite a few guys with 4WD swaps on there. They can help you out in that area better than I can.
 

Camar068

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Finally found it. I have $50 for a vss generator to use on the NP208 listed on my spreadsheet. Summit has it for $55. Hard bugger to find.

https://www.summitracing.com/parts/rpc-250-4153

You must be registered for see images attach
 

Camar068

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Played around with the green rouge and the valve covers to start to really make them shine. Reckon they cast these in sand?

Man alive at all the imperfections. I may just clean 'em up and paint them or just buy after market. Unless I relocate the coils, you won't be able to see much of them anyway.

Speaking of coils, it would be really nice if there was a flat coil pack that could be used instead. Might be a little easier to relocate and it look nice. We had a cavalier or something similar that had a flat coil pack and all 6 were in one assembly. Just something that popped in my head.

picture.php
 

Camar068

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10 yrs Air Force
been piddling around with this and that waiting for bonus time at work. Not as much as usual this year so this won't be done until the spring/tax time. I figure I need about $600-$800 to do that swap. I could sell an AR to come up with that, but not gonna risk it in case Hillary gets in.

Buy or build one now while you can.
 

Driver4r

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got a 5.3 and tranny yesterday (not the one above). Before we took it out, I fired it up and listened to it (no radiator). It ran fine. Didn't put in gear because I didnt think I was getting the trans.

Anyway, It dawned on me after we got home 3 hours later that trans fluid wasnt shooting out the disconnected coolant lines as it did on my 700r4 when I moved it a few feet w/o radiator in place. Is this a bad sign for the trans? It has fluid in it...well it leaked out the ass end when tilted.

Gave $1200 for both engine trans (2006 Silverado crewcab 114K miles)

On a 4l60/80 pretty sure they have a bypass valve for the cooler, On startup, the valve closes putting the trans into a closed loop to speed up the warmup process of the trans fluid, once the ECU sees the engine is at operating temp, or mabey its on a timer, I forget. But the valve opens to pass fluid through the cooler.
 

Camar068

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10 yrs Air Force
Didn't know that, Thx Driver
 

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