73-87 Chevy _ GMC Trucks => Engine/Drivetrain => LT/LS Swaps => Topic started by: Skunksmash on April 28, 2010, 03:46:36 AM

Title: A 5.3L swap?
Post by: Skunksmash on April 28, 2010, 03:46:36 AM
Hi all just wanted to stop by and pick the brains of a few of you guys who have done the 5.3L swap in one of the 73-87 chevy trucks. Instead of trying to rebuild a TBI motor to the specifications that I need, I have found out that my goal would be easier reached by using a more modern engine. I like a lot of aspects about the 5.3, and after searching here and a few other places, it seems like a bunch of people have done this swap. So I would like to ask, what all is involved?

Is it a huge expense, or a major pain in the rump?

What do you perceive would be the advantages of having a 5.3L over an older motor? (other than the fact that I hate carborators with a passion)

What year year/model should I get the 5.3 out of?

How do you make all the little things work? Like cruise and the gauges and stuff.

Those are just a few of the questions I have about the swap. I imagine that somewhere probly sells the motor mounts an major components by now..
Title: Re: A 5.3L swap?
Post by: VileZambonie on April 28, 2010, 05:02:37 AM
If you get a good deal on one and can handle doing it yourself it can be a worthwhile swap. The advantages are for stock to stock comparisson increased torque and fuel mileage. Although it's not leaps and bounds so again unless you get a really good deal the advantages won't really be seen in your wallet with the expense of the swap. A lot of people like to do it simply for the modern appeal and potential upgrades you can do to the LS engine. Anything you need for the swap is available for our trucks including adapters for the motor mounts.

Vortec heads are still a popular inexpensive upgrade for the 5.7L and TBI systems can be plucked from a donor rather inexpensive if your goal is inexpensive efi.
Title: Re: A 5.3L swap?
Post by: slammed79 on April 28, 2010, 01:47:55 PM
The sweet thing with the 5.3 swap is that most of them will take a LS6 cam and net a 100 hp increase. If you dig through Car Craft tech the dyno numbers are there, and that was with a carb if I remember right. The LS6 intake is good for some additional hp if you stay with the injection. These engines are basically destroked LS1's and pick up easy horsepower.

I'd reccomend finding a 99-03 engine, I can't remember the code off hand, but those are readily available complete from intake to pan for about a grand.
Title: Re: A 5.3L swap?
Post by: Stewart G Griffin on April 28, 2010, 03:44:03 PM
What is the weight difference between an ls and a sbc?
Title: Re: A 5.3L swap?
Post by: Skunksmash on April 28, 2010, 06:15:43 PM
Well I am looking to pick up some gas mileage over my wore out 5.7L that only gets 14MPG. Some of the trucks that the 5.3L came out of weighed more than my truck, and got around 18MPG. At least according to a few people on my other forums. My current engine is on it's way out, so I figure if I'm going to have to replace it, I may as well replace it with something good.

Also, I was hoping to find a lower mileage engine out of an '08 model truck, so that I don't have to rebuild it before I slap it in there. Basically I'm just looking for something that gets decent mileage, and won't break my wallet when towing a little boat or a couple jet-ski's to the lake.
Title: Re: A 5.3L swap?
Post by: Skunksmash on May 03, 2010, 05:11:37 PM
Been researching it a little more, it seems like people tend to stay away from the 08 and 09 engines due to a greater difficulty in the swap.
Title: Re: A 5.3L swap?
Post by: Captkaos on May 03, 2010, 11:57:16 PM
They were Displacment on demand and electronic throttle, which added to the complexity, but you can still use them, and if you can make them work you will benefit from the DOD for mileage.  Most people that you are reading about are after power not economy.
Title: Re: A 5.3L swap?
Post by: Skunksmash on May 05, 2010, 07:37:41 PM
Hmm, never heard of displacement on demand. Sounds weird though. Like it somehow changes the displacement of the motor. Which I always thought required a new crank
Title: Re: A 5.3L swap?
Post by: SUX2BU99 on May 06, 2010, 10:29:41 AM
No I think the usual way it works is it cuts the spark and fuel to 1/2 the cylinders when cruising. My 05 Magnum R/T had it too on the 5.7 HEMI.  And so did my aunt's 81 Cadillac with the infamous 4-6-8 V8 motor  :D Those were notorious for not working well but hey, it was 1981 technology! I remember watching the little onboard computer display say when it was firing on either 4, 6 or 8 cylinders. Without port fuel injection, I think the only thing it did was cut spark to the cylinders. I could be wrong though. The modern DOD systems I believe only switch between 4 and 8 cylinders.
Title: Re: A 5.3L swap?
Post by: Layne on May 06, 2010, 04:33:24 PM
I think it actuated a solenoid on the rocker arm so it wouldn't open. I'm thinking opposite of V-TECH?
Title: Re: A 5.3L swap?
Post by: team39763 on May 06, 2010, 08:57:31 PM
I think another problem with the 08+ motors is the VVT.  I think it involves going into the motor to deactivate it(change lifters).  If I could do my swap over again, I'd go with the 08+ motor(L92,L76,LS3).  The additional power is well worth the trouble to me.  I don't know any easy solutions to the DOD or electric throttle.  Since mine is a performance application, I'd probably swap on a Edelbrock intake and 4 barrel throttlebody with a LS2 ECM or something.
Title: Re: A 5.3L swap?
Post by: Skunksmash on May 06, 2010, 10:05:14 PM
I don't think I want a solution to it if it gives me better gas mileage. I'll get my power gains out of a set of long tubes and a full exhaust, as well as a few other mods that don't adversely affect mileage. But which is the most desireable '08/'09 5.3L engine? It seems that there are actually a few variations...
Title: Re: A 5.3L swap?
Post by: team39763 on May 07, 2010, 01:32:43 PM
I don't know much about the 08+ 5.3's, but if I had a choice, I'd get the one with the aluminum block.  Other than that, I'm not too sure on the differences between the motors(besides one or two being E85 compatible).  I think I remember reading that the DOD technology really isn't that great on these motors yet...like GM still has a long way to go before it's useful.  I think I remember a member on this site saying his work truck had DOD and the only time it went into 4cyl mode was coasting down a hill, so it really never saved him any gas.  I do know you can always get a good tune and help improve the gas mileage though.
Title: Re: A 5.3L swap?
Post by: Captkaos on May 10, 2010, 05:17:08 PM
Yeah the VVT also adds to the complexity.  If you are going to run it like it is you won't have any problems, but there are solutions to everything if you throw enough time and money at it.  LOL
Title: Re: A 5.3L swap?
Post by: choptop on May 10, 2010, 07:30:10 PM
My work truck is an 08 with the 5.3 DOD, and it doesnt seem to have anymore power or fuel economy than the 04 it replaced. Both trucks were 4x4, and both trucks carried the same load. i think the DOD is a waste
Title: Re: A 5.3L swap?
Post by: VileZambonie on May 10, 2010, 08:33:38 PM
I'll have to give you guys a lesson in VVT and DOD one day when I get a some extra time. I have some awesome animations. If you understand how it works you will appreciate it more. GM uses oil control to deactivate the lifter so the valves do not open. The off cylinders act like an air spring. If you are going to do this kind of swap for eceonomy take advantage of it.
Title: Re: A 5.3L swap?
Post by: inovermyhead on May 10, 2010, 09:13:04 PM
If it's simplicity and low cost that you are after you can't beat the LM7 5.3L engine in its carbuerated form. I however am doing the efi b/c I love remote start on those cold morning and hot afternoons.  ;D
Check this out if you haven't already seen it. Shows you the in and outs of installation although most of his upgrades are unnecassary and expensive you get the idea. http://www.sporttruck.com/techarticles/0912st_ls327_engine_swap_1973_chevy_c10/index.html
Another good resourse is Street and Performance and also Nelson Performance. A lot of guys like the Nelson tune and Alan is very helpful. Also check into BRP adaptors for some info. Hope this helps some.
Title: Re: A 5.3L swap?
Post by: choptop on May 10, 2010, 09:42:07 PM
Vile, I understand the principle of it, and really look forward to the lesson. I am curious as to why I dont see any difference with the 08 and the 04. I think the 04 had more power, and it actually got better mileage. Is the 08 much heavier than the 04. I was looking forward to better economy, but didnt happen. This is west texas, we dont have very big hills, if any, and most highway speed limit is 70mph. I got 19mpg out of the 04 and have gotten 18 in the 08, but on very few occasions.
Title: Re: A 5.3L swap?
Post by: SUX2BU99 on May 11, 2010, 09:54:31 AM
That's pretty cool that they can control the lifters too. VVT systems are a stroke of genius IMO
Title: Re: A 5.3L swap?
Post by: Skunksmash on May 12, 2010, 03:32:05 AM
As long as it doesn't have less power due to all that stuff then I'll probly just say screw it and leave it there.
Title: Re: A 5.3L swap?
Post by: uptonogood99 on May 17, 2010, 08:40:05 PM
The 5.3 motor comes in 4 different version. All can be figured out by the 8th dig of the vin IE "t" "Z" and sorry I forgot the other 2. The E85 motor, non DOD, has the most power, but gets the worst fuel mileage [about 15mpg]. All of these 5.3 started with "fly by wire" throttle system in about 03. If you are doing a swap, the best way would be to have a whole donor vehicle. This way you would have the engine, harness, ecm, fuel pump, fuel pump module, bcm, and most important the theft deterant system. The 06 and up vehicles also run the gm high speed lan for communications, which is going to make everything more difficult. I would suggest looking into the new crate motors GM is selling with stand alone ecms with a very simple harness. They are not cheap [about $8500] but I think a decent 08+ donor is probally going to run you about the same with more headaches. Good luck!
Title: Re: A 5.3L swap?
Post by: screamin86 on May 17, 2010, 10:53:53 PM
The aluminum block 5.3 I believe is the l33 the lm7 is the standard 5.3 and l59 is the flex fuel motor and the l59 is what I have in my yukon they came with 33lb injectors which is nice since I can mod a little more without worrying about needing injectors. Imo I'd stay away from any of the DOD motor for simplicity sake and if you ever mod it internaly like cams and such the DoD will be deleted anyway and lifters would need replaced. I believe the tunes for the newer motors are a little more expensive also but that's just me thinking lol. The 5.3 is a GREAT motor amd was originaly my intention for my truck but I want to do the swap on my car first so the truck got a 350. My 03 yukon has the l59 like I said and I've done some mods along with a tune frm nelson performance and in town I get roughly 14-16mpg and my personal best on the hwy is 23 and my wife drove it going to norfolk back in the fall and just barely got 25mpg on the hwy!!!! I say its not always what we get but on normal hwy trips we average 20+. I say its worth it and someday I hope to see a 5.3 between the fenders of my k10!
Title: Re: A 5.3L swap?
Post by: three8six on May 18, 2010, 12:39:53 AM
Anybody heard an aftermarket exhaust system on a DOD engine? Especially when its running on 4 cyl?
Title: Re: A 5.3L swap?
Post by: screamin86 on May 18, 2010, 01:25:02 AM
Ibe heard somes guys say it creates a odd drone on the hwy with it goes in to 4cyl mode.
Title: Re: A 5.3L swap?
Post by: three8six on May 18, 2010, 12:56:59 PM
Oh it sounds like a 4 cyl honda to me honestly with one of those fart cans.
Title: Re: A 5.3L swap?
Post by: Koots on June 10, 2010, 09:50:47 PM
The aluminum DOD 5.3L in my parents 09 Sierra gets incredible mileage and when you need it, will throw the ECSB Z71 around quite nicely when you hit the go pedal. Compared to the older models that seemed to be riddled with torque management to save the trans, it has excellent throttle response.

If i were to swap in a new engine, that would be the one i'd go for or a 6L (i've become addicted to the growl of my 2500HD :D)