How to find a good used motor?

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tRidiot

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I can't spend $5k on this truck, I have a blown head gasket, probably want to do a motor swap.

Problem is, I don't know much about this stuff, I have friends/contacts who can do it, I have a mechanic who could if I wanted to pay more.

Just I don't know how you 'find' a good motor - Ebay? I've got 275k on this truck, if I drop $5k into a motor swap I STILL have 275k on the rest of the truck, I just don't know that it's worth that. I considered doing a decent used motor and trans at the same time, but searching on Google it gets overwhelming quickly and of course crate motors are stupid high, rebuilts seem to be $2k+ just for the motor.

What motor "code" am I looking for anyways? I mean, it's not an LS1, LS2, etc. I know it's a GMT800 body, and a 5.3L motor, that's about the extent of what I know about the drivetrain itself.

People say, "just check local junkyards". Well... that sure seems like a crapshoot to me, you're just getting a random motor and taking someone's word that it came out of a truck with 100k miles instead of a 275k like mine, right?

I guess I'm just pissed and overwhelmed looking at this project. Luckily I have my 370Z I can drive for now, so I'm not in a massive hurry, but I've put so much time, money and years into the electrical/audio system in this truck, I'm not ready to walk away from it.

And I REALLY don't want a cay payment.

<edit>From what I am finding, this may be the L59 version of the LM7 (based on Wikipedia)? Is that what I should be searching for, "L59 replacement motor" or "used L59 motor"?
 
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wjburken

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I can't spend $5k on this truck, I have a blown head gasket, probably want to do a motor swap.

Problem is, I don't know much about this stuff, I have friends/contacts who can do it, I have a mechanic who could if I wanted to pay more.

Just I don't know how you 'find' a good motor - Ebay? I've got 275k on this truck, if I drop $5k into a motor swap I STILL have 275k on the rest of the truck, I just don't know that it's worth that. I considered doing a decent used motor and trans at the same time, but searching on Google it gets overwhelming quickly and of course crate motors are stupid high, rebuilts seem to be $2k+ just for the motor.

What motor "code" am I looking for anyways? I mean, it's not an LS1, LS2, etc. I know it's a GMT800 body, and a 5.3L motor, that's about the extent of what I know about the drivetrain itself.

People say, "just check local junkyards". Well... that sure seems like a crapshoot to me, you're just getting a random motor and taking someone's word that it came out of a truck with 100k miles instead of a 275k like mine, right?

I guess I'm just pissed and overwhelmed looking at this project. Luckily I have my 370Z I can drive for now, so I'm not in a massive hurry, but I've put so much time, money and years into the electrical/audio system in this truck, I'm not ready to walk away from it.

And I REALLY don't want a cay payment.

<edit>From what I am finding, this may be the L59 version of the LM7 (based on Wikipedia)? Is that what I should be searching for, "L59 replacement motor" or "used L59 motor"?
I get your dilemma - where do you put your money.

Are you being told that the motor in your vehicle is shot and can't be fixed due to the blown head gasket? People replace head gaskets and heads everyday.

As far as finding a good used motor, might consider looking around and see if someone has a running truck with a shot body that they are selling for cheap. I know around me, there are a few tahoes, silverados, suburbans that are in the $2000 or lower price range that run but the body is rusted out. Might be worth buying one like that and swapping the motor. That way you can hear the motor run before you buy it. Then you can part out the donor vehicle and recoup some money or just scrap it.
 
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tRidiot

tRidiot

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Yeah, right, so here's the deal.

I had the heads that have the problem with low-grade leakage, had to continually add coolant every few weeks or so. My mechanic was aware of it, he recommended a top-half rebuild, but we've put it off for several years, he said just keep doing what you're doing until it is leaking worse. No problem.

Last week I replaced the thermostat with one from O'Reilly - my heat wouldn't blow hot unless I was running 40 or so down the road, and even then wasn't great. So I replaced it and it worked, heat was much better, seemed to be cycling well, never overheating, etc., but I only drive a couple miles to work.

So Thurs, NYE, I took the family and we headed out on a trip, after an hour and a half, it overheated and stranded me. Limped into a mechanic, they changed the thermo again and then tested it and the head gasket it blown.

So due to the factory defective heads, I think it needs a rebuild and if we're going that far, we should probably replace it. That's my thought, anyways.
 

cheyenne383

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Where are you located? I have done the swap several times over the years a few different ways, here's a couple quick thoughts:

1. eBay sellers with good feedback are a good starting point, there are several dismantlers that specialize in engine packages. This would net some security and recourse, some even have a 30-90 day warranty. A quick search looks like you could get one shipped to you for <$1k, if it includes the harness and swap parts you could then resell your excess parts to someone more ambitious that is interested in a rebuildable engine and harness set up.

2. Local dismantlers/part out sellers. You would be able to have some in person recourse and could inspect your purchase prior to getting it.

3. Running and driving donor, you could pull what you need and easily part out the rest. If you have the time this would be an almost net zero investment after selling of parts.

Either way good luck with the repairs, I just spent the weekend redoing all of the grounds on my 292k 2006 Sierra... my fingers hurt but I spent $30 on wire and terminals instead of paying a car payment ;) I swapped the original 4.8 for a 5.3 out of a Tahoe in 2016 once I had coolant in the oil and it's still doing great!
 
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tRidiot

tRidiot

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However, I think I want to look at the heads on mine and make sure the replacement I get doesn't have the same heads, right? So in 50k miles or so I don't end up with this exact same problem?

I don't have the truck in my possession right now to look at the code on the heads... I remember my mechanic showed me a few years ago, it was stamped on the outside of the head and he said this is the one that is the problem. Is that something listed on most used motors like on Ebay or wherever?


<edit> Sorry, I'm in northeast Oklahoma, about 45 min north of Tulsa.
 

Mudsport96

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Find a local you pull it junkyard. Look for a truck the was t ***** or rolled over that way you know the engine ran when the vehicle went to the yard. Pull engine put in your rig. Some places like LKQ have engine pulling hoist you can use. Remember if it spins it wins.
 

Doubeleive

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buy 2 bottles of the blue devil "head gasket sealer", will cost you about $65-70, follow the directions as stated on the bottle, pour both bottles into the upper radiator hose when the engine is dead cold before first start. you will need 2 bottles because each bottle is for a 4 cylinder so it takes 2 bottles. leave the stuff in there and drive it. chances are 50/50 that it works, if it works then that gets you down the road again and leaves you plenty of time to save up for whatever you decide to do later.
the stuff works, did for me and others.
as far as looking for a engine you just need to go by your vin code such as vin T or vin Z, etc engine just has to match your vin otherwise you have to change the computer also.
you can pick up used engines for 800 or so or a rebuilt for about $2k and figure $1k for install at a independent shop.
 

Mudsport96

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as far as looking for a engine you just need to go by your vin code such as vin T or vin Z, etc engine just has to match your vin otherwise you have to change the computer also.
.
The only difference between the base 5.3 and the flex 5.3 mechanically are the injectors and fuel rails. Everything else is the same. So if he went that way all he would have to do is use his injectors and rails.
 

Doubeleive

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The only difference between the base 5.3 and the flex 5.3 mechanically are the injectors and fuel rails. Everything else is the same. So if he went that way all he would have to do is use his injectors and rails.

as long as the vin letter matches it's plug-n-play, doesn't matter what it comes out of, that is why you see yards listing used motors as vin T, vin Z etc,
 
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tRidiot

tRidiot

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Can I limp my Tahoe home to my house, do you think? I live 4.3 miles through light city traffic from the garage where it sits. It's not the best area of town and if I'm going to leave it for a few weeks while I try to find a motor, I'd rather it was at my house than at the garage. I mean, what further damage am I going to do?
 

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