How To LS Swap Your TJ

[Wildman]

Yep. I'd love to eliminate 98% of everything chrysler that isn't body and frame.then put a cj style flat dash and steering column in my tj!

Bare minimum chrysler electronics for lights and no more chrysler hvac.

You can flat dash it for a $$$$.

Be cheaper to just take a TJ frame and put a CJ body into it IMO...

That might be my next project. But I'd like to put a CJ2A or CJ3B body onto a CJ frame.

 

[Rickyd]

You can flat dash it for a $$$$.

Be cheaper to just take a TJ frame and put a CJ body into it IMO...

That might be my next project. But I'd like to put a CJ2A or CJ3B body onto a CJ frame.

Idk, I'm pretty handy and know where a couple halfway parted out cj's are that could donate a dash and a few things. I think the hot rod style tilt column and hot rod hvac would be the spendy part?

A good friend tried to give me a pretty nice sbc cj7 when the transfercase grenaded. I declined hoping he'd want to fix it some day.

 

[jesusfavela323]

Great writeup XCRN, quick question I did my 5.3 swap 6 years ago still on the process to finish, I started with 5.3 mated to a ford t19 and 205 TC, then changed transmission to 4l60E with np231J, I hope you guys can help me figure this out, do I need to send Low range signal to GM PCM? Everytime I tried to put 4low jeep would jump due to torque, last time I tried 4low just testing it with drive shaft only bolted with 2 bolts driveshaft double cardon snap, so if low range signal is require how do I hook it up gm PCM and would jeep 4low signal will work with gm PCM??

 

[Wildman]

If you're interested in installing a York A/C compressor on your LS engine JeepSpeed Shop has TWO (2) bracket kits left in stock.

 

[myjeep3]

Great writeup XCRN, quick question I did my 5.3 swap 6 years ago still on the process to finish, I started with 5.3 mated to a ford t19 and 205 TC, then changed transmission to 4l60E with np231J, I hope you guys can help me figure this out, do I need to send Low range signal to GM PCM? Everytime I tried to put 4low jeep would jump due to torque, last time I tried 4low just testing it with drive shaft only bolted with 2 bolts driveshaft double cardon snap, so if low range signal is require how do I hook it up gm PCM and would jeep 4low signal will work with gm PCM??

Did you use an adapter between tcase and tran? Did it have the connector for the gm pcm?

 

[XCRN]

Just thought I would throw this out there. Decided to do a cam swap while I have the radiator out and I was able to move the AC condenser and compressor out of the way without discharging it. So I highly recommend going soft lines throughout for serviceability reasons.

 

[Rickyd]

Just thought I would throw this out there. Decided to do a cam swap while I have the radiator out and I was able to move the AC condenser and compressor out of the way without discharging it. So I highly recommend going soft lines throughout for serviceability reasons.

View attachment 562366

View attachment 562367

What cam did you choose?

 

[5632]

The last thing I need in my TJ with an LS is a larger cam.

 

[XCRN]

What cam did you choose?

Summit Tow Cam I had lying around. I used it before and its very peppy all around. Never got idle dialed in but I have learned a lot more about messing with HPTuners the last year or so and I think I can dial in things a lot better. Should hopefully help bring back some of the lost power I had to sacrifice when notching the tail pipe to allow the rear track bar enough clearance to droop all the way. My next big goal is a rear triangulated suspension just to get rid of the stupid thing and then “un-notch” the tailpipe.

 

[NovakConversions]

Cost


I cannot tell you what your cost is since every build is different. I did mine for about $6000 if you exclude all the mistakes and changes I made midway through. Mine had all new engine accessories, rebuilt 5.3, and I paid for some good quality parts. I could have skimped on a lot and reduced cost. Keep in mind I bought 80% of the parts before inflation hit hard in late 2020. I have convinced my self I can do this for less than $2500 but will be janky for sure and I may try this out one day on a basket case TJ I have lying around.

Below is a table of what I would consider mandatory but you could probably price shop or omit things. PRICES MAY NOT BE ACCURATE, I cannot constantly verify this info since things change so much any more. This also does not include all shipping and taxes. I did not add any price for the engine it self. I can get a running 5.3 with a harness all day for $500 or less, but I hear its more like $1000-1500 out west. Or you may want to rebuild with all new accessories. I would also add another $500-1000 to account for extra bits you need to purchase like hose clamps, hardware, fittings, etc. The small stuff adds up quicker than you think.

Part	Source	Brand	Price	Part #	Note
Upper Rad Hose	Rockauto	Gates	$ 12.98	22345
Lower Rad Hose	Rockauto	Gates	$ 11.23	21615
Heater Core Hose 1	Rockauto	Gates	$ 10.26	28471
Heater Core Hose 2	Oreillys	Gates	$ 25.99	28480
Radiator and Shroud	Superior Radiator	Superior Radiator	$ 480.00	LSSTICKWRANGLERWITHSHROUD	Superior radiator - jeeps and wranglerSALL WRANGLER V8 CONVERSION RADIATORS HAVE A 90 DAY WARRANTY AND YOU MUST USE GREEN ANTIFREZE NOT DEXCOOL (wwwsuperiorradiator.com)
Radiator Fan	Summit	Flex-a-Lite	$ 99.99	105387	https://www.summitracing.com/parts/flx-105387
Transfercase Rebuild Kit	Rockauto	USA Standard Gear	$ 75.89	ZTBK231J
Slip Yoke Eliminator	JB Conversions	JB Conversions	$ 249.00	16-1200-1942	https://www.jbconversions.com/products/sye/np231j_std_sye.php
Transfercase Cable Shifter	Savvy	Savvy	$ 184.00	SAV-231S	Transfer Case Cable Shifter Kit for the 231 - Savvy Off Road
Front Driveshaft	Tom Woods	Tom Woods	$ 389.00		TJ/LJ Front Drive Shaft – Tom Wood's Custom Drive Shafts (4xshaft.com)
Rear Driveshaft	Tom Woods	Tom Woods	$ 389.00		TJ Rear Drive Shaft, Double Cardan – Tom Wood's Custom Drive Shafts (4xshaft.com)
Throttle Cable	Summit	Lokar	$ 86.95	TC-1000LS1	Lokar TC-1000LS1 Lokar Hi-Tech Throttle Cables | Summit Racing
Exhaust Manifold (LS3 Camaro)	Ebay	Used GM	$ 300.00		Price is based on what I have seen on ebay. You can find much cheaper options
Exhaust System	DIY or Custom		$ 1,000.00		Price will vary on where you go to and what material.
Fuel Regulator Bypass	G-Force	G-Force	$ 125.00	GF-JFRD-V2	Jeep Wrangler TJ Fuel Pressure Regulator | G Force (crossmembers.com)
Fuel Regulator	Summit	Summit	$ 38.99	SUM-230150	Summit Racing SUM-230150 Summit Racing™ Universal LS Fuel Filter Regulators | Summit Racing
Fuel Line Set Metal	Fine Lines	Fine Lines	$ 60.14	WGL0355SS	WGL0355SS - 97-06 Wrangler TJ, 3/8 Feed with 5/16 Return; Complete Fuel Line Kit; Stainless | SSTubes
Fuel Line Rubber 3/8 225PSI 15'	Oreillys	Gates	$ 51.15	27349	You will need around 10-15'
Fuel Line Rubber 5/16 40PSI 25'	Oreillys	Gates	$ 22.00	27003	You will need around 10-15'
Power Steering Hi Pressure Line	Rockauto	Gates	$ 28.79	353840	Modifications needed
Power Steering Lo Pressure Line	Rockauto	Gates	$ 20.79	353780
Trans Tunnel Plate	Summit	Mopar	$ 176.99	52059661AC	Mopar Replacement 52059661AC (summitracing.com)
			$ 3,838.14	Total Cost in Table

Table below is the engine mount options I know of, you only need to pick one. I personally used the Novak Weld-on mounts and they work, but I like the idea of the Holley mounts and will likely try that out for my next personal swap. Remember 6 cylinder frames can use bolt-on mounts or weld-on mounts. 4 cylinder frames require weld-on mounts..

Mounts Weld-On	Novak	Novak	$ 228.80	MMTJ-G3	GM Generation III & IV V8 Engine Mounts for TJ & LJ Wrangler Jeeps (novak-adapt.com)
Mounts Bolt-On	Novak	Novak	$ 236.06	MMTJ-G6
Mounts Bolt-On	Holley	Holley	$ 381.32	VK090181	https://www.holley.com/products/eng...and_crossmembers/engine_mounts/parts/VK090181
Mounts Weld-On	Daves	Daves	$ 225.00	LSEMTJ-KIT	https://davescustomsunlimited.com/jeep-tj-ls-series-and-gen-iii-conversion-engine-mounts/
Mounts Weld-On	MORE	MORE	$ 369.15	JM700	https://mountainoffroad.com/products/bomb-proof-motor-mount-kit-97-06-gen-iii-v8-v6

Below is the cost of using the Quick Draw Brand adapter with your own supplied transmission. I personally used a brand new AX15 that cost me about $2000 delivered to my house. Your cost on that may vary.

Trans Adapter	Quick Draw Brand	QuickDrawBrand	$ 695.00	AD-00015	LS to AX15 NV3550 bellhousing adapter kit for chevy v8 to Jeep 5 speed (quickdrawbrand.com)
Clutch	Rockauto	LUK	$ 218.99	04201
Trans Mount	Amazon	Crown	$ 28.99	52058551
Flywheel	Rockauto	Sachs	$ 88.79	NFW1050
Flywheel Bolts	Oreilys	Dorman	$ 16.99	14112
			$ 1,048.76	Total Cost of Adapter Setup	Keep in mind any material needed to make a custom plate to mount to the skid plate.

And one more major cost to consider is the wiring. There are 3 options to consider, the purchased standalone and new standalone you will need to have the PCMs tuned to remove the VATS which a lot of people will charge anywhere from $100 to $150 to do such a service. There is supposedly also a way to unlock the PCM for free, but it must be from a running truck. I think how it works is you need to start the engine in the vehicle then disconnect the PCM connectors while it is running.

Holley Terminator	Summit	Holley	$ 1,249.95	There are many part numbers that depend on what features you engine may have so keep that in mind when ordering a Term X
Standalone Harness			$ 600.00	Plenty of options, but they are all around the $600-800 range
DIY Standalone Harness			$ 180.00	Can be done cheaper, this is using a quality pre-made fuse box and accounting for loom, tape, and other materials.

Things to Consider

First one is gearing. The LS makes way more torque and power than the original engine and you just do not need the same numerically higher gears like you do with the original engine to out the power to the ground. For example, I am on 31s with an AX15 and started with 3.08 gears for about a year then went to 3.73 gears. I did not notice any real increase in useable power and it was just way louder at highway speeds and more fuel consumption. I think the AX15 OD of .79 is just too short for V8s but I feel as if a 6L80 can use the same tire and gears and would be ideal since its 6th gear is 0.67 and will drop the RPMs at highway speed to a more appropriate RPM. So keep all this in mind when choosing your components like transmissions, gears, tires, etc.

Mounting the PCM was somewhat of a struggle for me since I liked everything clean. When I had the terminator X, I mounted it behind the glove box, but had to remove the pocket of the glove box so it was useless. When I went to a stock Gen 3 PCM, I mounted it below the brake booster and machined a plate that replaced the tray that was in there so it could fit a PCM mount. It is tight in there, but it does fit.

You are likely going to have to use a SYE or tear open the transfercase if sticking with a NP231J, so just plan and budget to rebuild it. I have heard lots of people say its not strong enough, and maybe that true if you used it differently than me. I am not hardcore rock crawling, I play in the sand and trails and have not had that fail. I have had other things fail.

So with that said, plan to upgrade your drivetrain. I destroyed my stock Dana 35 bearings, destroyed a 175k mile NV3550, one U-joint on my new rear drive shaft (might have been more user setup error, not the part it self), and a transmission mount. All of this in 2-1/2 years, so upgrade accordingly.

You will certainly need a cable shifter for the transfercase since in most cases the TC is moved from its stock location.

Weight of an iron block LS is very close to a Jeep 4.0 so no need to worry about suspension mods to support an LS. An aluminum block engine will take off 100lbs. Depending on where you put it, the engine will sit behind the front axle entirely so congrats its now in the league of mid engine super cars like Ferrarris, Lamborghinis, C8s, Mclarens, and the legendary 88 Fiero with 95k miles and a case of PBR in the passenger seat.

I am not a mechanic and do not have a big space to work in. I have a little more tools than the average home garage and I had no wiring experience before this swap. I was able to require everything and do a frame off restoration with my hand tools, a welder, and a engine hoist. Nothing special.

Novak is a huge wealth of knowledge on this subject and I highly recommend you look into them. However they are still trying to sell their products so keep that in mind when reading their resources. Some of the stuff is easily sourced elsewhere for less like clutches, and flywheel bolts, but they sell high quality adapters that you should consider.

Now for fuel mileage, again to reiterate the specs. Stock 5.3 with headers, TBSS intake manifold, 92mm Throttle body, AX15, 3.73 gears, 31in tires and a 2in lift. I get on average with half country highway/freeway, half city I get 16.5mpg in the summer and 14.5mpg in winter. I have gotten 18mpg often on long road trips, and have gotten 20mpg once. I think it could be better with a better highway cruising RPM.

Conclusion

Hopefully this should help. I want to make a more thorough DIY on LS swapping these, and ill be working on videos when I get closer to doing my Gen 5 5.3 swap on my LJ. My first swap took me 6 months of planning and research before its first drive, and probably another 6 months after refining everything. This second swap is taking longer, since its a customer funded swap and I am only going as fast as they send me parts money. Was it worth it? Yes, but I wish I did it a bit differently like going with a different engine and trans setup to satisfy my personal goals with it. I hope to add some Youtube videos in the post below in the future. Good luck with your swaps!

Thanks for the feedback on our products. We found this information to be very helpful and we will use it for improvements.

You probably didn't write it up to help us, but we are certainly going to use it as helpful feedback.

We are always happy to take your phone calls as well. We are proud to be a stateside company since 1967: Give us a call: 435-753-2513
https://novak-adapt.com/index.htm

 

[XCRN]

Thanks for the feedback on our products. We found this information to be very helpful and we will use it for improvements.

You probably didn't write it up to help us, but we are certainly going to use it as helpful feedback.

We are always happy to take your phone calls as well. We are proud to be a stateside company since 1967: Give us a call: 435-753-2513
https://novak-adapt.com/index.htm

If you would like, I would gladly have more conversations on product improvements. I still have more LS Jeep projects to accomplish and plan on still using you for a lot of parts. I am looking at one of the 6L80 to NP242 adapters for my next project when I get around to it.

 

[NovakConversions]

If you would like, I would gladly have more conversations on product improvements. I still have more LS Jeep projects to accomplish and plan on still using you for a lot of parts. I am looking at one of the 6L80 to NP242 adapters for my next project when I get around to it.

Give us a call, shoot us an email, or even post the info here while you're working on it. I repeat it over and over again... We are a stateside company, and that gives us a great position in the market that not many others have. Also, any of you guys who happen to be in Logan, UT... Stop in and see us for a tour.

Phone: 435-753-2513 Website: https://novak-adapt.com/index.htm

 

[Wildman]

Give us a call, shoot us an email, or even post the info here while you're working on it. I repeat it over and over again... We are a stateside company, and that gives us a great position in the market that not many others have. Also, any of you guys who happen to be in Logan, UT... Stop in and see us for a tour.

Phone: 435-753-2513 Website: https://novak-adapt.com/index.htm

Next time I'm going through UT I'll make sure to stop by.

Thanks for joining the forum & Welcome. And thanks for offering parts for us & our addiction....

 

[XCRN]

Give us a call, shoot us an email, or even post the info here while you're working on it. I repeat it over and over again... We are a stateside company, and that gives us a great position in the market that not many others have. Also, any of you guys who happen to be in Logan, UT... Stop in and see us for a tour.

Phone: 435-753-2513 Website: https://novak-adapt.com/index.htm

One thing I think would be great and I would buy one is taking your tach emulator with cruise control and having it communicate with the universal cruise control units like Rostra or Dakota Digitial. It seems like you clearly have figured out the communication from the factory steering wheel cruise control buttons and were able to translate the signal to something a DBW PCM can use, could the emulator also send out basic analog signals to the 4 pin harness on the cruise control systems mentioned? This would open up a lot more engine options to cruise control while retaining the stock buttons. I hate the universal stalk sticking out of my steering column and I would love to get rid of it in favor of steering wheel controls. I think even TDI guys use Rostra/Dakota Digital for cruise control.

 

[NovakConversions]

One thing I think would be great and I would buy one is taking your tach emulator with cruise control and having it communicate with the universal cruise control units like Rostra or Dakota Digitial. It seems like you clearly have figured out the communication from the factory steering wheel cruise control buttons and were able to translate the signal to something a DBW PCM can use, could the emulator also send out basic analog signals to the 4 pin harness on the cruise control systems mentioned? This would open up a lot more engine options to cruise control while retaining the stock buttons. I hate the universal stalk sticking out of my steering column and I would love to get rid of it in favor of steering wheel controls. I think even TDI guys use Rostra/Dakota Digital for cruise control.

Hi XRCN,

Our E-TXCC will work with the Jeep Cruise Control & The GM PCM Gen III only. It will not work with the Gen IV or Gen V. ... Remember, the GM PCM only, it's not going to work with the Holley Sniper or others.

Great Question, hopefully this helps others with the same question.

__** Visit us at https://novak-adapt.com/index.htm or Give us a call, we are stateside in Logan, UT: 435-753-2513

 

[XCRN]

Hi XRCN,

Our E-TXCC will work with the Jeep Cruise Control & The GM PCM Gen III only. It will not work with the Gen IV or Gen V. ... Remember, the GM PCM only, it's not going to work with the Holley Sniper or others.

Great Question, hopefully this helps others with the same question.

__** Visit us at https://novak-adapt.com/index.htm or Give us a call, we are stateside in Logan, UT: 435-753-2513

Right I am aware it only worked on Gen 3 DBW, and that is something I was intrigued in but the next plans are gen V so I would not be able to use that. What I was thinking as far as new product development is develop a module to take the inputs from the TJ steering wheel controls and have the module output the analog signals used on the universal Rostra/DD cruise control units.

 

[XCRN]

So my radiator busted at the tube to tank joint like it did last year and it was not repairable by the local radiator shop this time. I really wanted to go with the Novak this time around but I did not have the time to wait the 10-15 days for it since I have a trip planned so I ended up with getting another Superior again and I am going to figure out a better way to mount it in hopes that prevents breakages at the tube to tank joint. But anyways the main point is I ordered it Monday and its showing up today so definitly want to make a comment on the lead time. This was also my experience when I bought the first one in 2020.

 

[Rolled Over Rubi]

So currently my mind has moved into the v8 swap area, and thought an LS would work perfectly, in the beginning i used to think i'd run LS3 in the jeep but part of me wants to throw an LSA inside. planning on the 4l80e transmission and keeping the stock rubi tcase. has anyone done it before? i've seen supercharged LS3's in jeeps but idk if i've seen an LSA yet. anything on it that would help make the swap and wiring easy?

 

[Wildman]

So currently my mind has moved into the v8 swap area, and thought an LS would work perfectly, in the beginning i used to think i'd run LS3 in the jeep but part of me wants to throw an LSA inside. planning on the 4l80e transmission and keeping the stock rubi tcase. has anyone done it before? i've seen supercharged LS3's in jeeps but idk if i've seen an LSA yet. anything on it that would help make the swap and wiring easy?

Did you read this thread? If you go over to Pirate they had a long thread with info about doing the swap that is 139 pages long.

https://www.pirate4x4.com/threads/5-3-jeeps.735270/

 

[Rolled Over Rubi]

Did you read this thread? If you go over to Pirate they had a long thread with info about doing the swap that is 139 pages long.

https://www.pirate4x4.com/threads/5-3-jeeps.735270/

Ah my fault, I was trying to find info all over the internet about LS swaps etc but couldn’t pirate never popped up on my end, thank you