XJTJ

Just picked up a 98 red XJ for 450 pretty solid jeep minus the rockers of course but needs an engine what year Cherokee is direct bolt swap

cruiser54

XJ Cherokee and ZJ Grand Cherokee 4.0L engine blocks interchange.

2000+ TJ Wrangler and WJ Grand Cherokee 4.0L engine blocks interchange.

XJ/ZJ blocks and 2000+ TJ/WJ blocks do not interchange without significant modifications. (1991 to 1995 YJ and 1997-1999 4.0L TJ Wrangler blocks will interchange in XJ/ZJ and visa-versa).

TJ/WJ 4.0L Engine blocks underwent clean sheet design changes effective in the 1999 WJ Grand and 2000 TJ Wrangler. These blocks are not interchangeable with XJ/ZJ engine blocks. The reason is motor mount bolt holes and belt driven accessory mounting bolt holes are in different locations, or not present at all, TJ/WJ vs. XJ/ZJ.


XJ: "Regular" (not Grand) Cherokees 84-01
ZJ: Grand Cherokee 93-98 (Gen1)
WJ: Grand Cherokee 99-04 (Gen2)
YJ: Wrangler 87-95 (Gen1)
TJ: Wrangler 97-06 (Gen2)

Ianf406

Aside from cruisers great post, you probably will want to avoid a post-1999 motor as they come with a crack-prone head and few slight differences as well as the pre-91 renix engines as they also have a few differences. You can of course make them work without a ton of work but if you grab one in between, it will be a little bit easier on you.

I sold my 170,000 mile motor for 500$ after doing my stroker this year-they are not as easy to come by as they used to be (at least up here) but if you hold out you should be able to find a cheap one. Good luck!

cruiser54

Agreed.

JamromXJ

1999 is ok up until mid-year. At some point in 7 or 8 1999 they started changing to the 331 heads.

Mine is a 6-99 with the 600 series head. If you can find one like mine, I have the best of both worlds. The better 99+ intake, with the more solid 99- motor.

Good hunting.

JR

XJTJ

I found a 98 zj with 128k for 250 waiting to see if guy still has it

Fred/N0AZZ

Sounds like a buy to me.

XJTJ

No answer hunt is still on took the head off piston went through cylinder wall cause for failure lol so back to hunt finding a bunch of earlier 90s 4.0 what's the easier swap if it comes down to it and what needs to be done

cruiser54

Cruiser’s HO into Renix Swap

This swap is easier than some will lead you to believe, generally those who have never done it. Those of us who have done it, like myself, will share with you the things that need to be done for a successful swap. Just think of it as swapping in a long block.

The HO and Renix have some differences but none that can’t be overcome very easily.

Any HO engine from an XJ or ZJ through 1999 can be used. One running change was that the rear of the head was no longer drilled and tapped for the temperature gauge sender beginning in the 96 model year. The sender can be relocated to the threaded hole in the thermostat housing taken from the HO engine. You’ll have to extend the wire to that location. Some brave souls even drill and tap the HO head for the sender.

You will be using the intake and exhaust manifolds from your Renix, along with all your sensors and wiring. Since the intake ports of the HO are slightly different, you use the Renix gasket. Exhaust ports are identical.
You will need to use your Renix distributor as it is different than the HO because they use different fuel management systems. The flywheel or flexplate from the Renix must be used so your CPS gets the correct signals. The valve cover from the Renix allows you to keep your CCV system intact and requires no modifications.

The HO block will have a plug in the coolant galley on the driver’s side of the block, closest to the front, which needs to be removed so your Coolant Temp Sensor can be installed in it’s place just as it is on the Renix. It requires a 5/16” square drive or a modified 3/8” drive that has been ground down to fit. Do this before installing the engine.

As for the knock sensor, which is located just above the oil pan on the driver’s side of the engine about mid way, all the blocks I’ve seen are threaded for it. If not, I’ve heard they may be drilled but not tapped. Tap the hole if that’s the case.


Revised 03/28/13

XJTJ

Found a 98 zj 4.0 that should be direct swap to my 98 xj right

cruiser54

As a "longblock", yes.

XJTJ

98 Xj swapping 98 zj engine anyone have any idea what this sensor is for on the zj block but not the xj I planned on using the xj wiring still will this matter

XJTJ

Bump

salad

Not sure what your picture is of, can you zoom in on or highlight what you're referencing? The sensor inmediately above the evil orange oil filter is the oil pressure sending unit.

You'll want to swap ALL sensors from your original engine unless you can 100% guarantee that the units are identical. Even then all sensors should be cleaned up and their ports cleaned out too. Sludge and scale and all that other buildup.

XJTJ

That sensor it's not on the xj block I pulled it's behind the oil filter