Advice on LS Swap

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brningdawn

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Wanted to get some opinions on the best route for my 1992 GMC K1500 RCSB.

I have a 2009 Chevy Silverado 1500 2wd with the flex fuel 5.3 in it. It's been my daily driver for a few years and was my mom's truck before she wasn't able to drive anymore so I know it's history since new. It currently has about 170k on it and mechanically runs great.

I've long wanted to put an LS in my 92 so my question is since I have the complete running truck and I know it's a sound engine should I use it as a donor vehicle or sell it and start with a pullout from the yard? The truck is worth $5-6k whole right now. So I could either sell it and use the money to start my 92 build or use it for parts. I don't know which would ultimately be more economical.

I also wonder what other parts I could take out of it. The seats are in good shape.

Should I keep the 4160 that's in the 92, have the 2wd out of the 09 converted to 4wd and use it, or start with a new 4wd 4160e/4165?

What about the rear axle? The 09 has the G80 in it. Both trucks have 3.42 gears but the 92 has open diff. Can anything be swapped from the 09 to the 92?

If I use the 09 I'd need an ac relocator bracket, some splicing of the two harness, new fuel pump, computer reprogrammed, mounts, and maybe an adapter on the flexplate depending on the transmission. Does that sound right?
 

Drunkcanuk

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Personally I would sell the 09, then find a complete LS and tranny that's already a 4x4. If the truck is in decent shape, no reason to gut it just for the motor and still have to deal with the difference tranny. Let someone else enjoy it while you buy something that's been pulled from a wrecked truck.
 

Schurkey

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That's a lot of work to go through to end up with a 5.3.

I can't see destroying a perfectly-functional '09 to use as a parts-donor. Sell the '09, buy a 4WD powertrain from some wreck. Preferably, something with more snort than a 5.3, and which already comes with a 4L80E.

Mind you, I'd be doing something with a traditional small-block, or a big-block swap. But that's me.
 

brningdawn

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Part of my reasoning for possibly doing it that way is knowing the history of the truck and knowing I have everything I need from the donor. Thought it might be easier. This will be my first engine swap where I wasn't putting the factory intended engine back in so I'm trying to keep the number of headaches down as much as possible. I know I will still probably spend a lot of time trying to get it going.

I want a 6.0 and 4l80 but I also never pull anything that the 5.3 can't handle with ease and I in Oklahoma so no mountains to worry about. I've been driving the 09 with the 5.3 for a few years and never felt like it didn't have enough power. The extra expense up front and the hit on gas mileage doesn't seem worth it. If I needed a tow rig I'd step up to a 3/4 or 1 ton. This is going to be mostly a daily driver, light offroader. I bought the 92 when I was 17, I'm 38 now, and they'll bury me in this truck. But it does need some love. She's all original and showing her age. When I priced out everything to rebuild, roller cam, ebl flash 2, throttle body stuff, etc.. to get her a little more pep you're spending as much as an LS swap. That's not even including new heads. I don't know. Hard to decide. The TBI is certainly simple and reliable, but it just feels like such a dog I don't know if I'd be happy with the results after doing all that.
 

L31MaxExpress

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I would keep the 5.7L before I considered anything smaller than a 6.2L myself. 5.3Ls are absolute dogs unless you spin them to the moon. All bark and no bite.

6.6L L8T/6L90E if I were doing a swap. I saw a complete pullout the other day with 3,000 miles for $5k
 

0xDEADBEEF

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I drive my son's 5.3 swapped truck and it never gets over 2k rpms. It will lock up in OD at ~45 mph at 1500 rpms and won't unlock going up the slight hills we have. It will also roast the tires if you don't ease into the throttle.
 

TonyM

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If you're going to sell the 09, I'd recommend buying a donor truck as opposed to just pulling an engine from a junkyard. You will use alot of the parts off the donor saving you time and money. There's also some details to consider, like do you want cruise control?
 

TreeGeared

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I am going to second or third selling the truck. Regardless of history I would go through any engine and at least replace gaskets, have injectors cleaned, replace any questionable sensors, ect. All that takes some cash and you would get more out of the truck whole rather than parting it. I am speaking from experience. I believe that engine in the 09 also has DOD which can be troublesome. If you get an earlier engine you will not have that and could get a drive by wire motor which would be a little less work to convert. As others have said getting one that is 4wd from the start will be a plus. Unless you plan on going with headers and duals consider grabbing the exhaust from a donor if it is in good shape and the same wheelbase. I was able to adapt the exhaust from a gmt800 with little modification.
 
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