5.3L (LM7) into OBS Sierra Classic

Sorry about the title ripoff 1BADC10 :laugh:

Well, this is my topic about the 5.3L swap I am doing on my project truck. The project truck is my 1980 GMC 3/4 ton 4x4, which currently has a TPI 350, SM465 3 speed standard with granny gear, and an NP205 transfercase. It started life as a 2wd 3/4 ton with a 350 / TH400 combo, with a lot of rust, and is slowly being worked towards being a nice tow rig for the summer :) My donor rig is a 2000 GMC 1/2 ton 4x4 with a 4l60e that was rolled 12 times last August.

I plan to run an NV4500 5 speed standard behind the 5.3L, and an NP241 passenger side drop transfercase. The 241 has a 40 tooth toner ring similar to the newer transfer cases, so the speed sensor shouldn't be a problem. My truck will have an electronic speedometer from a 90 - 91 truck, which should be compatable with the 4000 pulse per mile output signal from the ECM, factory tach with a signal doubling module I'll have to either buy or invent, a stock temp sending unit on the passenger side head, with a mechanical oil pressure gauge hooked up to the spare port that you can tap above the oil filter. Exhaust will be true duals, with out cats, so the rear two O2 sensors will be eliminated, and I plan to run F-body manifolds to avoid frame modifications. I am also planning on eliminating the EGR. I'm hoping to make this install as close to factory as possible, so I am hoping to run the stock air box, fuse block, ECM mount etc.

Now, for the questions! The engine harness seems pretty straight forward, basically leave it the way it is, but I need to get pinouts for the blue connector that goes between the engine harness and the cab harness, and if my assumption that the little 3 wire connector coming off the engine harness to the chassis harness is infact the fuel pump wires. More than anything, I'm hoping to figure out what all I can eliminate from the stock wiring, so I've got as clean of a setup as possible. I then plan to make a complete wiring guide out of what I learn for others to use in the future, so there isn't quite as much figuring to do when starting one of these swaps :)

Here are a few pics of my project truck, engine, and the donor truck:

http://www.zieglerdigital.ca/public/.../01.07.GMC.jpg

http://www.zieglerdigital.ca/public/...L/03.07.01.jpg

http://www.zieglerdigital.ca/public/...L/03.07.02.jpg

http://www.zieglerdigital.ca/public/...L/03.07.03.jpg

Nice title, Russ... :rock:

You'll find that I've posted (or have possession of) the wiring schematics for a 2000 Silverado (2wd). I doubt there's very much difference b/t the 2wd & 4x4 harnesses (engine-wise). Are you planning on wiring with the NBS fuse block? If so, it'll be easier, but if not, relays are your best bet for circuit reliability.

I'm sure you've read my thread backwards and forwards. If you still have questions, ask away. I'll post what I know, and others will help if you cannot find what you need on this site. :hshake:

Good luck! Git-r-dun. :smile:

Your thread, and one on LS1Tech have me pretty comfortable with what I have to do to get this sucker up and running again, the only thing I will have to add is the circuits for the check engine light, alternator light, diagnostics port, and AC stuff :)

Ok, couple of questions:

1) Fuel Pressure Sensor. Does a guy need to install one, or can it be deleted?

2) Fuel level sensor, same as above, do I need it, or can I live with just the stock sending unit for my factory gauge?

3) Low coolant sensor. I noticed the truck ran in limp mode if it was disconnected, but I cannot find any mention of it on the ECM pinout... Is it something I need, or can I use my stock rad with the stock overflow bottle?

4) AC sensors. My cab does have AC, but I will not get around to hooking it up for a while. I again noticed the truck ran in limp mode if I disconnected either sensor... Is it something that has to be hooked up, or do I have to get it disabled in the prom?

5) Since my truck has a standard tranny, what kind of an input is the ECM looking for from the clutch safety switch? My truck does not have one...

Thanks!

Russ

<div class='quotetop'>QUOTE(SierraClassic &#064; Mar 7 2007, 01&#58;24 AM) [snapback]85546[/snapback]</div>

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Ok, couple of questions:

1) Fuel Pressure Sensor. Does a guy need to install one, or can it be deleted?

2) Fuel level sensor, same as above, do I need it, or can I live with just the stock sending unit for my factory gauge?

3) Low coolant sensor. I noticed the truck ran in limp mode if it was disconnected, but I cannot find any mention of it on the ECM pinout... Is it something I need, or can I use my stock rad with the stock overflow bottle?

4) AC sensors. My cab does have AC, but I will not get around to hooking it up for a while. I again noticed the truck ran in limp mode if I disconnected either sensor... Is it something that has to be hooked up, or do I have to get it disabled in the prom?

5) Since my truck has a standard tranny, what kind of an input is the ECM looking for from the clutch safety switch? My truck does not have one...

Thanks&#33;

Russ
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Check engine light... uh... hmm... I haven&#39;t added that yet. I just keep my laptop handy when I drive the truck. Alternator light? When the volts gauge drops below 12V, I&#39;ll start looking to get to my final destination ASAP. I didn&#39;t make provisions for that. I did tie-in a diag port. There&#39;s a connector on the engine side of the harness that you can cut and splice in what you need. I found a descent interior harness off eBay, so I just used the stock connections.

Now... for fuel, I have an external mount fuel pump (255lph-rated) mounted to the frame rails. You may want to drop the tank(s) and drop in an in-tank pump. There is a p/n posted somewhere here, or on PT for that. Just be sure to replace any low-pressure fuel hose (rubber lines) with fuel-injected hose (or braided lines). If the 5.3L&#39;s intake has an integrated FP regulator, I don&#39;t "have" to worry about buying an aftermarket regulator. Let&#39;s not forget to install a filter in the line too. Low pressure filters will not due. Get a high pressure quick-connect or NPT-connection (screwed) type.

Your stock level sender should work well with most aftermarket gauges (providing you&#39;re going that route). I spent the extra on gauges b/c using the stock cluster with the paper element on the back would be a hassle to get it to work. Plus, to get an adaptor kit for the digi-to-analog speed signal would cost me the price of getting a complete gauge package. The aftermarket kit was what I wanted.

Low coolant... you will need to use the coolant bottle out of the NBS truck anyhow. The cooling system is a pressurized system. Transfer it over. Plus the connector is on the NBS harness.

Cannot comment on AC stuff b/c I have dealt with that issue yet. I am hoping to use the stock NBS compressor, but the in-cab component uses solenoid to force air to close valves to regulate switching functions for heat, max AC, low AC, and econo-mode (vent). I haven&#39;t put much effort in researching this since the truck&#39;s been down for a while.

Clutch Safety Switch - I am assuming this is a function that prevents you from starting the vehicle in gear. Is this not like the P/N safety switch? Does the donor rig have an A4 trans? If so, I&#39;m sure that is what that&#39;s for. If not, I have no clue... maybe someone can help with that. If you&#39;re getting rid of the 4L60E in the donor (if that&#39;s what it has), wanna "donate" it to a worthy cause? :laugh: Nevermind, it&#39;s a 4x4 trans. Couldn&#39;t use it anyhow.

You could have the 4l60e if you were a bit closer, only 50 000 miles on it from the factory, but I&#39;m a wee bit far away :D The project truck is the one with the standard, and I assume the ECM only uses the input to control wether or not it will energize the relay / gain some insite on when you are shifting. I don&#39;t mind rigging something up for the second part, but I would prefer to have the ECM just start the truck regardless of if the clutch is down or not.

Check engine light should be easy, just provide ground to my existing service engine soon light (truck currently has TPI)

Fuel pump I was planning on a walboro 255lph in-tank pump, already know which one I need :) Is there any problem with running high pressure rubber fuel hose from the rear of the rig to the front? I have steel lines right now, but they were never intended to be permenant, and are not bent or anything... I&#39;d run the hoses up on the inside of the frame rail, and make sure they are well secured :)

I&#39;ll see what I can do to mount the NBS rad in my truck, but mine is a 73-80, so I am not entirely sure if I&#39;ll be able to pull it off yet...

As far as the gauges go, I already know exactly how to make my analog speedo work, and still make the ECM happy as well. Oil pressure is mechanical, and water temp is easy too, just buy the S&P adapter for my stock sending unit.

I was just wondering if the ECM needed an input from the tank pressure sensor, and the level sensor to run properly, or if the pressure sensor is only used for the EVAP / level sensor for the low fuel alert / gauge?

Well, I got the whole engine pulled today&#33; Discovered something that has me worried -- The rad has a chunk of side tank missing at the bottom where the little round stud thing used to be, and there is was absolutely no coolant in the engine at all... I did run the engine like that, once for around 5 - 10 minutes :sad:

Should I be worried and pull the heads, or stab it in, and see what happens? :eek:

Other than that, no broken parts or wires anywhere, should be a pretty reasonably straight forward swap from here :)

Though, this does raise the question, do I find myself a new rad from another NBS truck, or can I somehow rig my old one in?

Rig up the old one. Stab the engine and don&#39;t worry about it. No need rebuilding something if there&#39;s nothing wrong with it. If you find something wrong, it won&#39;t take long to pull it out.

Well, what do you guys think I should do for my tranny?

My truck currently has an old SM465 standard transmission in it. That is a 3 speed tranny, with a granny gear. I really like standards, and personally don&#39;t trust autos very much, any truck I&#39;ve had with an auto has self destructed in very little time...

Also means that my truck is already set up with a hydro clutch setup, with all the pedals, the standard tranny reverse lights etc.

I&#39;ve already bought an NV4500 I plan to drop into my truck instead of the SM465, so I&#39;ll have a 5 speed standard with overdrive. I also bought the proper transfercase needed to bolt onto the back of the NV4500, which will provide the correct VSS signal the PCM needs, and also drops on the proper side of the truck.

However, its proven to be a real challenge to bolt the NV4500 up to the 5.3L. I&#39;ve got a few ideas of how I may be able to get around most of the problems with the recessed flywheel / pilot bearing, but I am concerned about how I&#39;ll start the thing, as suddenly the starter will be too short as well.

So, that brings me to consider putting a 4l80e into my truck instead... It has the 32 spline output shaft, and adapter I need to bolt my NP241 t-case one, and is fairly reasonably beefy too. However, it has a lot of parasitic losses, and I&#39;m still not a fan of autos regardless... I can probally get it reasonably cheap, but it will still cost me a fair bit...

Do I hold out and figure out the starter issue with the flywheel, or do I stab it in with an auto?

BTW, 4l60es are out of the question, my truck is frequently used to haul water, and up to 8 quads on a 18 foot flatdeck trailer. I&#39;ll burn it up real quick...

http://eshop.advanceadapters.com/commerce/...product_id=2540

Bingo&#33;

I think this may be exactly what I need&#33; Just kinda expensive... 700 bucks before shipping, which will be around 150 in itself...

I suppose, if I cannot find a cheaper route, I can always fall back onto this, lol

Well, been a while since I had anything to update you guys with -- This project has taken a bit of an interesting turn :)

I just picked up an LQ4 6.0L to drop in instead :D Still planning on going with the NV4500 / NP241, but I got a smoking deal on the engine, and simply couldn&#39;t pass it up :D

Once the snow melts again, and I get my 6.0L here, I&#39;ll update with some more pictures :)

Man... must be nice. I wouldn&#39;t mind getting an LQ9, but money&#39;s tight... even for a good deal.

Congrats&#33; Git &#39;r dun&#33;

any new progress?

I&#39;ve been collecting parts for the transmission in the form of the clutch stuff. I just recently picked up a flywheel and clutch kit. While I was there, I also put in the order for an Advance Adapters bellhousing :)

I&#39;m still waiting on the 6.0L to get here, the guy I bought it off has been out of province for a few weeks, but has been in pretty regular contact, so I&#39;m not entirely worried about him bailing on me (though, the concern has crossed my mind...)

Once my AA bell and engine are here, I can figure out what size of throwout bearing I need to make things work, then it&#39;ll be ready to drop into my truck. I&#39;ve already bought the fuel pump + lines, engine mount adapters etc.

Basically playing the waiting game now, once things arrive it should pull together fairly quick :)

<div class='quotetop'>QUOTE(SierraClassic &#064; May 2 2007, 10&#58;33 PM) [snapback]92154[/snapback]</div>

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Basically playing the waiting game now, once things arrive it should pull together fairly quick :)
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What up?&#33;?&#33;?&#33; :wave:

<div class='quotetop'>QUOTE(1BADC10 &#064; Jun 10 2007, 08&#58;33 AM) [snapback]96236[/snapback]</div>

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What up?&#33;?&#33;?&#33; :wave:
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Well, things certainly arn&#39;t going my way with this swap...

The 6.0L has most definitely fallen through on me, same with the NV4500. Unfortunately, I&#39;d sold my 5.3L to have the cash to pay for the 6.0L (fortunately, no money was spent before it fell through on me), and I&#39;d sold my old 350 & SM465 / 205 to pay for the 5.3L in the first place.

That basically means that I have only got a transfercase for my truck now, no other engine or transmission at all :bash:

I&#39;ve been keeping my eyes open, but I can&#39;t seem to find any other engines for sale at a reasonable price anywhere, and despite my best efforts, I wasn&#39;t able to buy my 5.3L back either :(

So, I&#39;ve been keeping my eyes open, but my attention on the project is being diverted to getting the bodywork done until I find an engine.

Gah, I hate it when people let me down after I sell the stuff I have to pay for things =/

Sorry to hear that... Not to give false hopes or anything... I&#39;ve been looking at 350s and 383s last night. Seems like I&#39;d be paying out the wahzoo for a 400hp turn-key crate. With the thought of doing yet another swap... my wife would put me out for sure.

I think that a 6.0L is still cheaper than a new 300 some horse crate engine, as long as you can get a donor engine cheap enough, lol

I think that once I get off work here (this is my last shift for a couple of weeks), I&#39;ll go cruise a couple of insurance auctions, and see if I can&#39;t find myself a totalled donor with a good engine. Sell the transmission etc and make a bunch of my money back

Ha Ha... must be nice to cruise insurance auctions. I don&#39;t have access.

I think I&#39;m holding on the 5.3L for quite a few years. Just revamped my tune a bit, and hope to test it out later today.

dang it, I wish I hadn&#39;t sold my 5.3L :sad:

I dunno what I was thinking :bash:

<div class='quotetop'>QUOTE(SierraClassic &#064; Jun 22 2007, 09&#58;05 PM) [snapback]97529[/snapback]</div>

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dang it, I wish I hadn&#39;t sold my 5.3L :sad:

I dunno what I was thinking :bash:
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Yea... well I&#39;ll tell you this... do not go out and just buy any old setup that you see just to buy it. Think of it this way, you have the opportunity to get a 6.0L (LQ4 or LQ9). Trust me&#33; If I find a descent 6.0L, I&#39;ll make you a GREAT deal on a tested and broken-in 5.3L. :cool:

That would be awesome, but I can hardly imagine the cost of shipping all the way up to Canada, lol :D

My 5.3L was a good running engine with about 50 000 miles or so on it, the 6.0L was a good running engine too, but the guy totally bailed on me, and left me high any dry...

I doubt I will be able to find another one at a reasonable price again, those kind of deals only come up every once in a while, lol

Well, I might have found myself another 5.3L, with less miles, for the same price as the first one to boot! I still have the engine mount adapters here, and the walboro fuel pump is still in the EFI tank, not to mention the fuel lines run up to the front of the truck ;)

I managed to get my original 350 back, but have since found out that it has a wiped cam lobe (hense why I got it back :( ) and it hasn't run right at all. Didn't come with the TPI either :(

However, one concern is that I dunno if I have the buying power to get the engine right now... Its only 800 bucks, but I have not worked since September due to school. Tuition, food, rent etc without working totally drained my bank accounts, lol Maybe my parents will give me a loan...

Well, I dunno guys, I think this might be meant to happen!

Just so happens that I sold some parts today to the tune of exactly 800 bucks!

The fella who picked up the parts was extremely interested in some other parts I have too, which would easily pay off not only my visa, but also pay off the rest of the parts I need for my conversion, and feed me for January too!

Following your thread with interest as I'm basically doing the same swap. Still in the gathering info and parts stages but I already scored my LS6 and cleaning it up. Got tons of questions but doing the recon before I just start posting away. At any rate looking foreward to following your thread good luck...

DOAH! Hosed again!

The engine was mostly there, but it certainly was not as advertised, lol it was missing the MAF, and what little wiring was left was totally butchered... Oh well, as of tonight's rather unusual success in selling stuff / having debts paid up etc, I have a $3000 dollar 6.0L fund, so I think I am gonna go for the big guns right away!

Regardless, post away with your questions! I want to make this thread as in-depth as possible to make it easier for future 73-87 swappers :)

$3K is a nice amount. It's the little things to get you closer to the finish line that's gonna eat away at that price. Don't rush to get the next greatest thing unless you're ABSOLUTELY sure that's the deal you want.

Good luck!