Researching options for a 98 TJ I just bought

I had thought about buying an entire donor vehicle but just didn't have the space for it. I already deal with tons of people flaking out on other craigslist deals I didn't want to deal with drawing out a heartless (engine-less) vehicle sitting around for months then paying someone to tow it away because I got tired of the eyesore. I picked up a running 5.9 for $400. I showed up, he started it, let it run for about 5 minutes to check everything over, gave the guy a deposit and he had it pulled the next weekend on a pallet for me. Included the entire harness and PCM with it too. Granted, I had to buy a transmission separate, but the Dodge engines can mate up to the Jeep transmissions.

I had looked for a couple months at engine options but another deciding factor is the Mopar engines are actually cheaper around here (while I was looking) than the LS options.
 
TreverStevens said:
I'm in the midst of the 5.9 Magnum swap. It is a little more straight forward than the LS swap because everything is within the Mopar family so to get everything to "talk to each other" is easier. If I were you, I'd honestly enjoy the TJ over the summer, wait until the winter months to start the swap, don't be in too big of a rush to start it. My engine went out so I was forced to start the swap, luckily I have another DD and taking my time on the swap.

https://wranglertjforum.com/threads/project-red-headed-stepchild-a-restoration-build.6125/ great Magnum swap guide here and as you'll see towards the end @RangerRick is more than willing to answer questions and has an abundance of knowledge. I have a couple other sources I've been pulling my info from on my swap if you want me to send those in a PM to you. One resource is a YouTube series from a guy up in MT, he might even be nearby, I can't remember his exact location.
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Thanks. I've looked through that Magnum swap thread. Lots of info. I keep bouncing between a 5.3 or 5.2. I guess each its pros and cons. I've read that Magnum is a relatively easy swap. But others have said there are more options on the market for the Chevy engines. I have the AX5 so I'd need to change tranny too. I might be able to get an AX15 that's been built. $600 for that. He says he spent $900 to build it.

But I'm tempted to do what you say. Just enjoy it for a while and see how it goes until next year. New tires before winter are a must though. I'm down to the wear bars now. I just can't be sure how well it will drive with 35"s and the 2.5l with 4.10 gears. And I don't want to spend the money on 33"s and wish I had gone bigger.

But this Silverado came up on my searches and $500 seemed like a great deal to take advantage of. Maybe what I'll do is have the tear down be my next project. Get the dirty work done, and if I decide against the swap I have a cleaned up 5.3L and 4L60E ready to sell.
 
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TreverStevens said:
I had thought about buying an entire donor vehicle but just didn't have the space for it. I already deal with tons of people flaking out on other craigslist deals I didn't want to deal with drawing out a heartless (engine-less) vehicle sitting around for months then paying someone to tow it away because I got tired of the eyesore. I picked up a running 5.9 for $400. I showed up, he started it, let it run for about 5 minutes to check everything over, gave the guy a deposit and he had it pulled the next weekend on a pallet for me. Included the entire harness and PCM with it too. Granted, I had to buy a transmission separate, but the Dodge engines can mate up to the Jeep transmissions.

I had looked for a couple months at engine options but another deciding factor is the Mopar engines are actually cheaper around here (while I was looking) than the LS options.
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If I swap the engine I'll need to do the trans too since I have the AX5. I might have a line on an AX15 though. $600 for that. He says he spent $900 to build it.

I feel like I'm swimming in information...
 
I will mention some points here since my conversions have been brought up.

If you can roll-your-own harness or blend two different MOPAR harnesses together yourself then the MOPAR swap would be cheaper and easier since you can keep your original dash and gauges. The swap can be made to look factory. It can be built like your TJ came with a V8 from the factory since the engine would be from the same MOPAR family and run all the gauges. You have a 98 so your TJ is CCD bus making the Magnum a better choice than the HEMI which uses the PCI bus. Read my build and see the link to Hotwire Auto on what bus is in what MOPAR vehicle for each year.

If you can't build a wiring harness yourself and if you have the funds to build a new dash with different gauges then the GM Vortec family of V8's makes a good swap candidate. It won't be like the Jeep came from the factory with the GM V8 but they do make really great power and are highly supported in the aftermarket.

I recommend you read my build thread to get an idea of the swap scope and buy a donor in it's entirety because there will be lots of small things that can nickel and dime you to death otherwise.

Get the factory service manuals for both the donor and the TJ you are swapping to, they will come in handy. Again, see my build thread on what manuals I used to blend my own harness and save a big chunk of cash there.

If you are good with a new sub-harness and building a new dash with modern gauges for a GM swap, then that is an option that is viable. I had an LM7 5.3L V8 in my CJ-7 until I swapped a Cummins Diesel in it's place recently. The Jeep ran and drove great with the Vortec though however it was a CJ with all mechanical dash and no ECM in it whatsoever so easier to use a GM sub-harness with it. A CJ is a different animal than the partly computerized TJ Wrangler.
 
Thanks for the helpful reply. I've looked over that build thread, but I'm definitely going to look it over again in more detail.

I think that I can deal with the harnesses just fine. And I'm not enthused about doing things like replacing the dash. Time and money are factors there. That's why I was leaning toward the 5.2. While there might not be as much support for swap kits and such, it sounds simpler and less expensive.
 
Advanced Adapters has the Magnum V8 conversion motor mounts that will index perfectly to weld up. I test fit my engine several times but if you use their dowel locator pins and weld it in using the recommended locations, it fits perfectly and I could have skipped all the test fits out of the gate to save a day of trials. You may need a 1" body lift though I will say that. I have a 2005 Rubicon hood with the sound dampening liner in it, I needed the 1" to clear that and for my tummy tucker with the Atlas II transfer case install. Everything fit very tight but perfect like from the factory finish which I wanted it to look like.

Also I may add that it is highly desired to use a ZJ Grand Cherokee manifolds and a transmission from one so the starter will be on the passenger side where Jeep has them for more clearance on your drive shaft etc.

If you get the engine from a Dodge truck fine but the starter is on the driver side and manifolds are different. They tend to dump farther back and hit the firewall requiring clearancing. This needs to be addressed and may require some fitment of the motor mount location from the dowel pin location on the AA Magnum V8 conversion mounts. ZJ 5.2/5.9's are preferred for better fitment but use of a Dodge Magnum is acceptable and many do this because of ease to find a wrecked truck or SUV over the ZJ. Some people buy aftermarket center dump shorty headers for the Dodge truck engine but I have read of many unhappy with the header solutions out there and they have also been very costly. I would get the exhaust manifolds and Y pipe off of a ZJ if goinig with the ZJ engine, and the fan from the 5.2L ZJ, use the fan shroud from a 4.0L TJ, everything will fit like it was from factory with no real custom fabrication there. Also the power steering pump and bracket on the ZJ doesn't stick out as much so it gives more driver side inner fender well room for other things. It will also interchange with a PSC or AGR high performance unit that was made for the TJ.

Only 1998 5.9L Limited ZJ's would have the 46RE (A518) HD transmission. If you get a 5.2L ZJ 1998 will have the 44RE which the only real difference between it and the 4.0L 44RE is the bellhousing. It may have more steel plates in the clutch packs but basically the same thing so for cost, you could just re-use the 44RE and it would work ok in all but really hopped up engines. If you are running a 5.9 or a really built 5.2 and you want pure beef, you've gotta find a 46RE and they are rare in the ZJ, Only about 15,000 made with the 5.9L engine. I went and ordered a re-manufactured 46RE from a 5.9L ZJ because I didn't want to trust a used 44RE I had from the ZJ. It cost but no headaches and a 2 year, 36K mile warranty to boot!

If you are going for the 5-speed manual, either the AX-15 or the 3500/3550 will work. On the 3500/3550 series, use the bellhousing off of a Dakota or Durango 3.9L V6 Magnum powered transmission. The bellhousing fits the V8 as they are the same pattern and bolts right up to the 35xx 5-speed. A 12" clutch fits from the same application Dodge and there are a couple different sizes you could go with.

Note: 5.9L engines are EXTERNALLY BALANCED motors and require a matching flywheel or flex plate that is for the 5.9L engine. The 5.2L is internally balanced so any flywheel or torque converter flex plate will work that is not balanced for the 5.9L engine. Pay attention to this tidbit or you may end up with bad vibrations in your engine as a result. This is often overlooked and means everything has to come back apart to fix if the wrong parts are mated to each other.

RR
 
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tykesplace said:
Thanks for the helpful reply. I've looked over that build thread, but I'm definitely going to look it over again in more detail.

I think that I can deal with the harnesses just fine. And I'm not enthused about doing things like replacing the dash. Time and money are factors there. That's why I was leaning toward the 5.2. While there might not be as much support for swap kits and such, it sounds simpler and less expensive.
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If going for the 5.2L, try to find a 1998 ZJ 5.2L V8 4x4 that runs and drives for cheap and use it as your donor. You can get the engine harness and blend it with the TJ charging and the dash plugs. Also you can add the fuel pump & sender wiring to it. The ZJ will have the harness laid out correctly with all the correct plugs for the engine. I used the TJ charging harness for mine and added the TCR (Transmission Control Relay) to the PDC under the hood for the 44/46RE transmission. Everything fits better if you can find a ZJ as a donor for your conversion. All you will have to find is a Dodge RAM 5.2L 4x4 Automatic ECM to use since the ZJ has security and will not run without the BCM computer mated to the ECM harness, (something I wouldn't do to overcome the security no start).

If running a manual instead, then you can keep the manual transmission harness parts from the TJ and get the bellhousing from a Dodge truck or SUV that had the NV-35xx transmission in it. Same as the above posts, same clutch as whatever the bellhousing came from but you will need a 1998 Dodge Ram 1500 4x4 manual transmission ECM in that case.
 
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I have a 5.9 / 46re from a ram in my tj. The biggest problem I have is the lack of good center dump headers. Ranger Rick brought up using Grand Cherokee 5.2/ 44re combo, and I think that's a good move.

I just bought an exhaust manifold for a 1988 dodge 360 pickup to try to use on my 5.9. The outlet is only about 1.75 inches, so I am going to open it up for 2.25 inch pipes. They is plenty of meat to open it up.

Good luck with the swap
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RangerRick said:
If going for the 5.2L, try to find a 1998 ZJ 5.2L V8 4x4 that runs and drives for cheap and use it as your donor. You can get the engine harness and blend it with the TJ charging and the dash plugs. Also you can add the fuel pump & sender wiring to it. The ZJ will have the harness laid out correctly with all the correct plugs for the engine. I used the TJ charging harness for mine and added the TCR (Transmission Control Relay) to the PDC under the hood for the 44/46RE transmission. Everything fits better if you can find a ZJ as a donor for your conversion. All you will have to find is a Dodge RAM 5.2L 4x4 Automatic ECM to use since the ZJ has security and will not run without the BCM computer mated to the ECM harness, (something I wouldn't do to overcome the security no start).

If running a manual instead, then you can keep the manual transmission harness parts from the TJ and get the bellhousing from a Dodge truck or SUV that had the NV-35xx transmission in it. Same as the above posts, same clutch as whatever the bellhousing came from but you will need a 1998 Dodge Ram 1500 4x4 manual transmission ECM in that case.
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I found a 98 Grand Cherokee for $400. 5.2 auto. 165k miles. 600 mile round trip though. I’d spend about $180 on fuel. Not sure if it’s with the trip.

I’m also checking to see if it has a hp30 front.
 
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