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LM4 5.3L and 4L60E swap into 2004 LJ

LBarr2002

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#1
20170721_220622.jpg

I decided long ago that if anything major happened to the 4.0/42RLE in the LJ that it would not be repaired or replaced with the same. I knew I wanted an aluminum block LS for the weight savings, and I wanted a gen III motor. I've been keeping my eyes open for a good deal to have stashed away for the future, and this showed up.

It's an LM4 out of a 2004 Buick Rainier with around 140,000 miles. I got everything, MAF to O2 sensors, Accessories to transfer case, throttle pedal, TAC module, harness, ecu, for $1,000.

It will probably be a couple of years before I actually do this, but I figured if I waited until I actually needed it i would end up paying too much for the drivetrain I wanted or compromising and going with an iron block. This means a major hurdle is taken care of, and I can gather the other parts needed if I see them used or on sale.

I plan to use the gm engine and trans, adapted to the 231 jeep case (unless I win the lottery and get an atlas). I'll probably use Novak for most of the conversion parts.

I've done some preliminary research and have an idea of the conversion. I'll update this as I have time. I'll take any input and advice also...
 
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LBarr2002

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#2
Parts and Decisions

Trying to put some of my thoughts on "paper". This will be mainly ramblings for my own benefit for now. When the time gets closer, I'll clean it up.

Motor mounts:
Numerous options. Novak, AA. Liking these so far Daves Customs https://davescustomsunlimited.com/je...engine-mounts/. Need to look at how they handle the steering shaft bearing.
Going to need a camaro ls1 pan and pickup.

4l60e to np231J:
1) Novak adapter, requires transmission teardown and replacement of output shaft.
2) AA adapter, requires 27 spline tcase input, case will be apart for rebuild and sye anyway, has provision for gm vss. Easily run dual vss, one for ls pcm one for stock jeep gauge.
3) 231c (s10) front case half - need to look at this closer.

Looks like AA is the way to go. GM vss before tcase, jeep VSS after case, doesn't require teardown of trans like Novak does. I shouldn't have to ever separate engine and trans going this route.

Trans mount:
Most likely going to use a Barnes trans crossmember kit if I can make it fit. This way I can drop the skids without supporting trans and isolate vibrations better.

Fuel system:
1) Novak sells a kit to bypass the regulator in tank and use corvette filter regulator. Pretty sure one of my friends with machine shops could accomplish the same thing as their bypass...
2)05-06 tj pump supplies needed 60psi, but not sure if direct swap into my tank.

I have a good old 04 pump I can mess with. Anybody have a 05-06?

Purchased Novak kit.

Cooling:
Ls swap specific radiator with electric fan activated by pcm. Many options. Trans cooler built in or separate?
http://www.wwwsuperiorradiator.com/jeeps_and_wranglers looks like a good option. With trans cooler and fan for $450.
-coolant tank?

A/C:
1)Stock ls compressor, stock location, notch frame.
2) high mount kit, aftermarket compressor
Most likely go #1.

Power steering:
Gm pump should connect to jeep box with some combination of factory hoses.

Wiring:
I'll send off harness and pcm to someone who knows what they're doing. Eliminate PATS, downstream O2 sensors, etc.
http://www.150tunes.com/costs.html
Jim's performance
Note to self, discuss tow/haul mode for trans.
Needs pull up resister for Novak tach emulator.

Gauges:
I think I want to run the factory gauges.
1) battery - no issue
2) fuel - factory pump and sending unit, no issue
3) temp - find a place for jeep sensor. Back of passenger head there's supposed to be an m12x1.5 plug. Either adapt to 3/8 npt or drill and tap, if adequate clearance to firewall.
4) oil pressure - jeep sensor installed in hole drill/tapped in filter housing. Issue here is late TJ gauge is just a dummy light with a needle and I'm not sure if I'm ok with that...
5) speedometer - if using the AA adapter with dual vss, should be no issue
6) tachometer - Novak signal generator?

Alternate would be the dash panel for 4 small and 2 large aftermarket gauges and the whole array...

Trans shifter:
? Would like to adapt original, but we'll see.

Tcase shifter:
If case ends up near stock location, use stock. Else, Novak cable.

Purchased Novak cable.

DBW pedal:
I have the buick pedal but it is massive and has the mechanism for height adjustment. Not sure if I'll modify it using jeep pedal parts or buy an aftermarket smaller pedal.

Driveshafts:
Rear will be new for sye. Front lengthen or shorten as required.

Intake:
90 degree elbow to passenger side with MAF adapter and whatever amsoil filter fits, with a prefilter sock.

Exhaust:
Since this came from a vehicle designed for an inline engine, hopefully the stock manifolds will work. I don't see how you could get anything that fits tighter, it just depends on the dump location. I'll get a local shop to bend the rest of the system. It will cross over to passenger side and run single 2.5-3.0" basically in the stock location. Upstream O2 only, but will probably still have a cat of some sort. Not sure on muffler choice. I want it quiet with just enough rumble to know it's not a 4.0. Have to keep it a sleeper.
 
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LBarr2002

LIFETIME
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#3
Running Costs

Purchases:
-$1000 - Drivetrain: engine, transmission, harness, ecu, pedal, etc.
-$90 - Novak fuel integration kit FSK-9704NR, regular price $179.
-$40 - spare NP231.
-$115 - Novak cable shifter. Regular price $179.
-$487.76 - Advance adapters 50-0435. Regular $567.10.
-$191.24 - Crown RT24005 SYE.
-$190.51 - Dave's Custom Unlimited motor mounts. Regular $190 + $29.01 shipping.
-$60 - Novak tach emulator E-TX61. Normal $194
-Harness: $300+ $23.40 shipping there and $10 shipping return.
-Computer: $100 +$17.05 shipping there and $10 shipping return.
-$401.88 - LS1 oil pan, windage tray, dipstick, dipstick tube, pickup tube
$425 - Superior radiator with trans cooler, fan, and shroud.
$83.71 - Novak/Lokar shifter arm and bracket.
$28 - assortment of ls fuel rail connectors off NC4x4.

Extra costs
$44.36 - exhaust manifold gasket and ARP bolts

Stuff to sell:
- Rainier/Trailblazer/Envoy transfer case, front driveshaft, front differential
- Jeep 4.0, 42RLE
- Brown Dog MML
 
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LBarr2002

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#5
I was able to grab a cached version, so going to put the remainder of the important discussion here:

Me:
Anyone have an old or spare 2005-2006 fuel pump sitting around? Also would be interested in an already upgraded np231j (sye, wide chain, cable shifter...)
I'm looking for the complete assembly that drops in the tank, preferably one someone replaced, doesn't have to work. I want to see what the difference in the '04 and '05/'06 pump is to see if I could just drop the '05 assembly in and have 60psi. But, there must be some significant difference because aftermarket tanks are listed differently between those years. I don't know if it's evap differences, wiring, fuel line connections...

Fatty:
The newer 05-06 pumps are 16" high and the 03-04 are 18" high so there is a difference of 2" that need to be accounted for, and the gasket sizes are somewhat different too.

Me:
Ah, ok. So I would probably need the whole 05 tank to go that route.

Just found decent pictures of both tanks on eBay. Looks like the 05 tank has different/more emissions crap. Scrap that idea, Novak fuel regulator kit or home built...

Fatty:
You could fab up a drop down plate but it would be a lot easier to change the tank I believe.

Me:
I tried to run through everything again yesterday to make sure there wasn't anything else I should get off the buick before it gets parted and scrapped. Transmission shifter came to mind. There are so many aftermarket options out there, lokar, art care, winters, b&m, then every one has stock gate, rock gate, reverse lockout this and that... why not use a stock shifter? The jeep shifter is only gated for 3 speeds and od is a button on the dash. I might could make it work but would have to redo the gates and indicator. I contacted the guy I got the driveline from and I'm probably going to get him to send me the buick shifter and cable assembly. The buick doesn't have a gear indicator on the shifter, it's digital in the dash. Then this came to mind:
ShifterOEM.jpg
93-97 camaro. It's relatively flat and similar size/shape to the jeep shifter, gated for 4 speed 4l60, and in junk yards everywhere (and possibly one in my dads parts car).

I dug through a ton of information on speed sensor signals last night. By far the cheapest way to adapt the 4l60 to np231j is by using a np231c case front half from an s10 blazer. This also gives you a 6 gear planetary instead of the jeep 4 gear. The jeep vss is retained in the back half of the case. The issue here is you only have the jeep vss, which puts out a 3 pulse per rotation signal. The gm pcm is looking for 40 pulse per rotation. A competent tuner can program the gm pcm to use the jeep signal, but that signal is after the tcase reduction. So, the trans won't shift right in low range unless you feed the pcm a separate signal telling it that you're in low range.

I checked with Wayne of 150tunes.com and he confirmed what I was already expecting. You really need to have the gm vss in front of the tcase and jeep vss behind. The Novak kit requires the trans to be torn down to replace the output shaft with a 23 spline shaft. The AA kit replaces the tcase input with a 27 spline gear. My tcase will be rebuilt anyway, so AA is the way to go. I shouldn't even have to split the engine and trans apart.

After having this thing in my truck for a week, I was really ready to get my truck back... The unloading went pretty smoothly with a borrowed boom for the tractor. Moving it to it's resting spot didn't go so well. My first attempt at a rolling pallet failed and nearly dumped the motor on my concrete floor. Luckily, Tripp delayed his beer drinking pool swimming plans and helped me rectify the situation. Thanks again!
20170729_190227.jpg

Tripp:
So...Wouldnt take ALOT to build a interface to go from 3 ppr to 40 and a "enable" bit to adjust the output for lowrange... Id have to sketch out that math tho...

EDIT, thinking more about this, you just need the 3ppr for the jeep speedo correct? how would the tach get its signal? Probably be easier to go from 40 to 3 vs 3 to 40.

Me:
There's no reason to translate the signal to 40 from 3 or vice versa. The gm computer can be programmed tonuse the 3 pulse, so all you would need to do it connect the gm vss wires to the jeep vss and let it's signal feed both places. There was also something about one being a square wave and one a sine wave, but that can apparently be worked around.

I saw where people had another switch or button on the dash that told the computer it was in low range, but I'm not doing that. There was another that had, or was trying to, mount a switch on the tcase lever to activate when in low. Extra complication that I don't want... Dakota digital has all kinds of signal converters.

Tach in jeep is based off the crank position sensor. Novak has a module to emulate the jeep cps signal from the gm pcm to run the tach.

Scribzilla:
This project makes my frame swap seem like a piece of cake!

Scballa18:
I used a np241C from a 1994 chevy truck with a JB conversions SYE. VSS works. Still need a switch to tell the computer it is in low range. Lokar trans shifter.

Me:
So your case has the 40 pulse gm vss. What is this In? I'm trying to keep the jeep 3 pulse vss also for the speedometer.

Did you find a floor shift np231c instead of electronic?

I really don't think it will be that bad. I'm making it harder on myself with the detail stuff to keep it stock appearing, but to put it in and make it run shouldn't be hard. It's been done so many times there's info everywhere. Just have to sort through it all to figure out which way is going to work for me.

Scballa18:
Yeah, the 241C has the stock vss with 40 pulse. It is in a TJ, but I do have aftermarket gauges. I am not sure, but I think all the old np241's are floor shift.
 

LBarr2002

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#6
Between Bing and Google I was able to grab cached versions of all 3 pages. I'll need to redo the pictures, but at least I got most of it back!
 

LBarr2002

LIFETIME
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#7
Updated and changed a few things. One advantage to having a drivetrain sitting around when multiple other vehicles in the family share the same engine is spare parts. Dad's truck has had a couple issues and he's robbed the MAF and an 02 sensor off this motor. Guess I have to add those to my list... :smile:.

Still just trying to collect anything I can. Have a Novak cable shifter on the way, and waiting on Dave's Customs Unlimited to put out a good discount code for the motor mounts and a few other things.
 
#8
I would suggest on letting someone do at least a drive along tune. There's a guy I've used before who can throw you a start up tune in and will be good enough to get you to him on a stock tune. He can release a lot of extra and fine tune it for your application. Jim's tunes sucked from my experience.

Charles Barber 864-419-8908
In Pelzer

Shane Billings/Nemesis Racing 864-978-8191
In Enoree

Both are good guys. I have used both of them, both do a good job.
 
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LBarr2002

LIFETIME
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#9
I would suggest on letting someone do at least a drive along tune. There's a guy I've used before who can throw you a start up tune in and will be good enough to get you to him on a stock tune. He can release a lot of extra and fine tune it for your application. Jim's tunes sucked from my experience.

Charles Barber 864-419-8908
In Pelzer

Shane Billings/Nemesis Racing 864-978-8191
In Enoree

Both are good guys. I have used both of them, both do a good job.
Yeah, I need to update my thoughts on tuning. I've talked to JR a good bit about his. A guy from NC4x4 did his harness and he's happy with it and it was reasonable. For tuning, he was planning to use RPM Performance in Columbia. I talked to Charles a lot about the G8 and he knows his stuff. I just didn't get to tune it before the trans started acting up.
 

LBarr2002

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#10
I made the next big step today. Morris 4x4 had the advance adapters 4l60 to np231 adapter cheaper than anyone else, plus 10% off and free shipping. And, they have 15% off and free shipping on crown products, so placed a separate order for sye.

This means I'll have everything to assemble the drivetrain on the pallet. The only thing left on drivetrain will be getting the f-body oil pan.

For timeline, I'm tentatively thinking collect all parts by Thanksgiving, and start swap after the Christmas trip. That will give me 4 months till OSCAR... :eeek:
 

LBarr2002

LIFETIME
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#13
Dave's custom unlimited motor mounts ordered. I was trying to hold out for another 20% off sale, or more, but with the looming tariffs and other companies raising their prices, I decided to buy at 15% off. It basically equaled free shipping.

I was also going to order an ECU mount, oil level sensor plug, and a vacuum nipple he sells, but I found an ECU mount and plug I like better for less. I looked at the brake booster vacuum line that they sell the nipple for and my motor has the complete line with check valve that will plug right in the jeep booster. Small win!
 
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LBarr2002

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#14
I wasn't 100% sure what I was going to do for a tach since the Novak emulator would cost over $200 with shipping. I figured I would check idle rpm with my scanner at first and go without for a while. But, I scored an emulator for $60 from a guy who tried to use it with a gen IV LS3 and it wasn't accurate.

I contacted Charles Friday and he gave me a contact in Greenville for the harness work.
 

LBarr2002

LIFETIME
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#16
Props on your planning and prep for this build. It should be a smooth transition when the time comes to swap everything.
Thanks Matt. As much info as there is out there on this swap, there aren't many that really document the parts used, costs involved, etc. With the Samurai, I knew what had to be done and had everything down to the radiator and heater hoses before I touched it. I won't be quite that prepared since there's more unknowns involved, but hopefully I'll be close.

As I've been researching and asking questions, multiple times I've had people say I wouldn't go through all the trouble of an ls swap for just an "old junkyard truck motor". People seem to think you need an ls3 and 400-500 hp to make it worthwhile. My response has been "I'll take 100hp and 100 ft lbs over stock (50% increase in both) and 100 lb weight savings any day". I'll also have less money in the swap than the average LS3/6L80E would cost alone.

That being said, I want to quantify the improvements. I'm going to try to weigh the jeep before and after. I know what my average fuel economy is now (14.5) and I'll compare it after. I'll probably do some non-scientific stop watch 0-60 times before and after. My question is, if I'm going to have it dyno tuned after, should I get this thing on a dyno for a baseline? Would anyone be interested in seeing the real wheel HP numbers before and after?
 
#17
Thanks Matt. As much info as there is out there on this swap, there aren't many that really document the parts used, costs involved, etc. With the Samurai, I knew what had to be done and had everything down to the radiator and heater hoses before I touched it. I won't be quite that prepared since there's more unknowns involved, but hopefully I'll be close.

As I've been researching and asking questions, multiple times I've had people say I wouldn't go through all the trouble of an ls swap for just an "old junkyard truck motor". People seem to think you need an ls3 and 400-500 hp to make it worthwhile. My response has been "I'll take 100hp and 100 ft lbs over stock (50% increase in both) and 100 lb weight savings any day". I'll also have less money in the swap than the average LS3/6L80E would cost alone.

That being said, I want to quantify the improvements. I'm going to try to weigh the jeep before and after. I know what my average fuel economy is now (14.5) and I'll compare it after. I'll probably do some non-scientific stop watch 0-60 times before and after. My question is, if I'm going to have it dyno tuned after, should I get this thing on a dyno for a baseline? Would anyone be interested in seeing the real wheel HP numbers before and after?
a current condition dyno would be sweet, if you can get that turd of a transmission to transfer the power to the dyno.
 
#19
I think that would be pretty cool, but likely not worth the money spent to make the pulls. If you could find someone doing a dyno day where you get a pull and print out cheap it may be worth it. If you do a dyno tune with Charles you will get the most bang for your buck for sure.
 

LBarr2002

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#20
Anticipation is killing me. Spun the motor over a couple times tonight to make sure it hadn't seized up. All good.

Probably going to order the radiator in the next couple weeks, and oil pan whenever I can get by the dealer during business hours.
 
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