Need input... Gen 3 swap

KROME

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Jul 16, 2023
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Florida
I have a 2005 Sport that is my daily driver. I put about 200miles a day on the Jeep just going to and from work. This Jeep is also my play toy. I live on the panhandle of Florida.

I am putting the pieces together to do a Gen 3 LS swap and I am looking for a good marriage with an automatic transmission. I DO NOT WANT TO GO MANUAL...

I'm wanting this to take place in the next few months.

20231015_172713.webp
 
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I'm not surprised by that, it's not like the 4.0 is fuel efficient, but still can't wrap my head around driving a TJ 200 miles a day from a gas and maintenance standpoint.

I don’t see an issue from a maintenance standpoint, other than wearing out expensive offroad tires. The gas would suck though.


I do close to 100 most days, and I’m a semi-broke ass college kid 😆
 
Some claim the LS engines are more fuel efficient than older V-8's but I don't have any first hand knowledge one way or the other.
My Magnum 5.2 V-8 got the same or slightly better than others with a 4.0.
As far as driving a TJ 200 miles per day? I see it being no different than driving a Econobox the same distance.
Put some A/T or street tires on it and go for it. I never had issues with driving my TJ long distances.
 
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Some claim the LS engines are more fuel efficient than older V-8's but I don't have any first hand knowledge one way or the other.
My Magnum 5.2 V-8 got the same or slightly better than others with a 4.0.
As far as driving a TJ 200 miles per day? I see it being no different than driving a Econobox the same distance.
Put some A/T or street tires on it and go for it. I never had issues with driving my TJ long distances.

LS engines in general are easy to set up for a great compromise of power vs fuel economy. I've never had one in a Jeep, but every one I've had in a Camaro or GM truck has been plenty powerful while still knocking back close to 20mpg with mixed driving, while one of my 1500's got 30mpg driving to OBX all loaded down a few years ago. (Not going to lie....the fuel economy on that trip really surprised me) I can't imagine a Jeep setup properly with an LS would be any different. I have no first-hand experience with the Dodge V-8s however, but most people I know with them complain about fuel economy. Those are generally either bone stock, or heavily modified for racing....no real inbetween.

Regarding daily driver use of a TJ for 200 miles or so: I don't cover that much mileage every day, but sometimes I do. As long as the TJ is capable of the tasks I have for that day, I drive it. I don't even own a vehicle that gets what others would consider good gas mileage. I have my 2500 crew cab Silverado with a 6.0, my TJ, and my Fiancée's JKU. I decided as a teenager I'd rather be happy and enjoy what I'm driving than drive something I don't care for and save some gas money.
 
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As far as driving a TJ 200 miles per day? I see it being no different than driving a Econobox the same distance.

Um, a generic Civic averages 35 mpg. Until that Jeep is at 30 mpg or better, I see a big difference.

200 per day, 5 days per week, 50 weeks per year (2 for vacation) = 50,000 mile per year. 1,428.5 gallons at 35 mpg, 3,333.5 gallons at 15 mpg (common for our Jeeps). At $3.25/gallon, the op could save about $6,200/year by parking the Jeep and driving an econobox. Hell, year 1 pays for the economy car, year two pays for the bulk of an engine swap in the jeep.
 
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Um, a generic Civic averages 35 mpg. Until that Jeep is at 30 mpg or better, I see a big difference.

200 per day, 5 days per week, 50 weeks per year (2 for vacation) = 50,000 mile per year. 1,428.5 gallons at 35 mpg, 3,333.5 gallons at 15 mpg (common for our Jeeps). At $3.25/gallon, the op could save about $6,200/year by parking the Jeep and driving an econobox. Hell, year 1 pays for the economy car, year two pays for the bulk of an engine swap in the jeep.

I worked with a guy that drove 108 miles each way to work every day. He drove a Cadillac that needed premium.

It made him happy.
 
I’m a semi-broke ass college kid 😆

You're not trying hard enough...you should be a completely broke ass college kid! Embrace it! :D


One factor of fuel economy typically overlooked is how you drive your chosen vehicle. My other vehicle is an '04 MINI Cooper S, I can get 36 mpg out of it if judicious with use of the throttle and gear selection. But if I want to hear the supercharger scream like a banshee (and I do, frequently :p), top out my shifts and take corners at speed, I can easily halve that mpg. Easily.
 
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04 MINI Cooper S

I've always wanted one of those to play with. There's just something cool about them, even though I'm primarily an American Muscle kind of guy. But I've heard they can be a nightmare to work on, kind of unreliable and expensive. So I bought a TJ instead 🤔

One of these days, though..
 
I've always wanted one of those to play with.

It's like a street legal gokart for adults. :)

Owned it longer than any other vehicle in my life (15+ years), done all the wrenching on it and it still puts a smile on my face every time I drive it....not unlike the developing situation with my recently acquired LJ. (y)
 
LS engines in general are easy to set up for a great compromise of power vs fuel economy. I've never had one in a Jeep, but every one I've had in a Camaro or GM truck has been plenty powerful while still knocking back close to 20mpg with mixed driving, while one of my 1500's got 30mpg driving to OBX all loaded down a few years ago. (Not going to lie....the fuel economy on that trip really surprised me) I can't imagine a Jeep setup properly with an LS would be any different. I have no first-hand experience with the Dodge V-8s however, but most people I know with them complain about fuel economy. Those are generally either bone stock, or heavily modified for racing....no real inbetween.

Regarding daily driver use of a TJ for 200 miles or so: I don't cover that much mileage every day, but sometimes I do. As long as the TJ is capable of the tasks I have for that day, I drive it. I don't even own a vehicle that gets what others would consider good gas mileage. I have my 2500 crew cab Silverado with a 6.0, my TJ, and my Fiancée's JKU. I decided as a teenager I'd rather be happy and enjoy what I'm driving than drive something I don't care for and save some gas money.

There are people who did the Magnum V-8 swap that claim they were getting 20 MPG with the 5.2 and 18 MPG with a 5.9 but I can't verify this. I didn't drive mine on the road enough to ever getting any fuel mileage readings. Plus I was running M/T tires and 5.13 gears.
My current engine definitely isn't made for fuel efficiency. It's a stroked 5.9 making it a 6.7.

While I'll agree that there is a ton more support for the LS I'm not a fan of them in 2002 and older TJ's. The Magnum is a easier swap and the Dodge PCM talks to the stock dash. I'm daily driving a 1997 Ram 1500 and get around 13-14 MPG with it.

To help the OP as was already stated the 4l60e would be the transmission to use. If you're dead set on a LS swap. If you were to do a Magnum V-8 swap a 5.2 with a 44RE would be good. Find one from a Grand Cherokee as the starter is on the passenger side as opposed to a Dodge version is on the drivers side.
 
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Some claim the LS engines are more fuel efficient than older V-8's but I don't have any first hand knowledge one way or the other.
My Magnum 5.2 V-8 got the same or slightly better than others with a 4.0.
As far as driving a TJ 200 miles per day? I see it being no different than driving a Econobox the same distance.
Put some A/T or street tires on it and go for it. I never had issues with driving my TJ long distances.

My LS equipped 05 Corvette gets amazing gas mileage- It is probably the most fuel-efficient car our family owns.

But I’ll walk right past it to get in the jeep anytime.

I’ve said a lot of things about Jeep ownership on here but I really don’t know what all makes me enjoy them so much.
 
My LS equipped 05 Corvette gets amazing gas mileage- It is probably the most fuel-efficient car our family owns.

But I’ll walk right past it to get in the jeep anytime.

I’ve said a lot of things about Jeep ownership on here but I really don’t know what all makes me enjoy them so much.

The only LS platform vehicle I've ever owned was a Chevy 2500 with a 6.0 and that thing got worse fuel mileage than my Ram. I really disliked it. And was glad to trade it for a Dodge.
 
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