swapping out inline 4 for a inline 6

rksagario

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I have a 98 TJ with a IL 4 and I would like to replace it with a inline 6.
do I have to change the transmission and gears also?
 
The gears can stay most likely (do you know what gearing is in it now?).

The transmission will need to be swapped out though. Be prepared for a huge project. This is by no means a few day project.
 
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I have a 98 TJ with a IL 4 and I would like to replace it with a inline 6.
do I have to change the transmission and gears also?
Sell it and put that money towards one with a 4.0 in it.
You will need to swap out the engine harness, PCM, transmission, t-case unless you have the auto, probably front and rear drive shafts, and the big challenge will be moving the harness around without damaging enough to cause a failure. I just tried to do a manual to auto swap between two 05 TJ's and due to the fragility of the harness and needing to swap them between the two rigs, I had to tell the owners it wasn't going to be possible.

Unless you find a donor rig for cheap that was crashed in the back, it will very likely be much more work than it is worth in the end.
 
I 100% agree with Blaine. It's honestly not even worth it. Sell the vehicle for one that came with a 4.0 stock.
 
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Agree with Chris and Blaine. Swap projects are a huge time and $ investment!
 
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If your gonna go through the process of doing a swap, do something better than what was am available stock option.

Outside is Beautiful
 
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If your gonna go through the process of doing a swap, do something better than what was am available stock option.

Outside is Beautiful

I agree completely. Why bother swapping in something that already came in a Jeep? That's rather senseless. If you're going through all the trouble of doing a swap (and believe me, it will be a shit ton of work), you may as well put a V8 in there, or something else.
 
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I agree completely. Why bother swapping in something that already came in a Jeep? That's rather senseless. If you're going through all the trouble of doing a swap (and believe me, it will be a shit ton of work), you may as well put a V8 in there, or something else.
Or a 4bt! 8)

Outside is Beautiful
 
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Some people really enjoy creating expensive and complex problems for themselves. If you are one of those people, by all means do the swap. If you prefer to enjoy your jeep out in the open and not in a garage, the sell it and buy one with the bigger engine or, even more fun, put a turbo kit and other mods into that squirrel and turn it into something unique and cool.
 
Swapping the four banger out for a six may not be a waste of time, but it is a waste of money and a TJ. The SE's are what they are (I drive one and love it.). The 4 bangers do quite well off road, and have acceptable performance on the road when used the way they were intended. When you open up that can of worms called an engine swap, all bets are off. Realistically speaking there are few 4 to whatever swaps that ever get completely finished. If the end state is supposed to be a functional, reliable TJ most engine swaps never get there in the real world. There always seems to be one more thing to replace or repair.

There are a couple of things to note if you have an SE and want to make peace with it. Weight. The 4 doesn't like extra weight. Avoid extra weight like the plague. Just like in long distance back packing ounces add up to pounds, and pounds kill performance. Put the TJ on a strict diet. Speed. The 4 banger will never perform like a six or a V8. It will never be a fast mover. Especially on the hard surface roads, and most especially on the Freeway. It's a fact of life, so you need to get used to that and go with the flow. The SE's are a riot to drive on twisty two lane blacktop, but there are lots of cars out there that will do better. Accept that fact and have fun with the top down in the sunshine. Off road. The SE's do just fine off road where the speeds are MUCH slower. Don't load them down with gear and armor and such, and they will keep up with most any other Jeep out there, and do much better than a lot of other rigs off road. Gearing. The SE is very sensitive to gear ratios and tire size. 27" tires and the 4.10 gear ratio is about perfect both on and off road. The upper end seems to be around a 33" tire and 4.88 gears on the stock Dana 30 / Dana 35 axles. You are always going to have to run more gear with the four to make it work, but it does work. It works well, in fact. The bottom line with the four is essentially this: Don't get all wrapped around the axle with what the rest of the TJ community is doing with their rigs. You will get poor results following the lowing herd, and be disappointed in the results. Build the four the way it wants to be built and you will be pleased with the results, and surprise a lot of people both on and off road. Or drop $10 - $15k or more and a year or more into a reliable drive train swap and impress the neighbors. My take is spend the money on time and gas to develop your driving skills. Spend a little money on the required mods to get you those last few miles back into the more inaccessible places.

Otherwise, trade the four in for a six with an automatic next weekend and dig out the parts catalogs and your check book. Only you can decide what you want to do.