t.mcginley.jr

Hi everyone,

Been lurking for a few weeks now, finally joined the site. I bought a 2000 XJ a couple weeks ago with 202k miles on it. Bought it with the engine knocking and/or broken piston skirt, either way it sounds awful.

Usually I rebuild engines like this, but I'm looking for something easy so I was just gonna buy a good used motor and swap it. I've done my research somewhat and know that I can drop an engine in from any XJ, ZJ/WJ and I believe pre-1999 TJ. Anyway, I found a good deal on a 1996 GC engine with all accessories and think it's a good candidate. Guy has a video of it running and of the dash showing good oil pressure and no CEL.

Question is, it has 167k miles on it. It should last a good while longer right? I'll probably do some maintenance on it before I drop it in, and swap on my newer accessories (yes, I'll have to fab up a bracket for the coil packs), but I'm not looking to replace bearings or rings. How long do 4.0's usually last mileage-wise?

Also, motor mounts from my XJ should bolt right to that block correct?

BlueRidgeMark

I've got 252k on my daily driver. Just checked compression a week or two ago and it was 145-150 on all cylinders.

dans98xj

I have 263,000 on mine still runs like a top. are you sure you need to swap motors? I had the same problem with my 98 TJ years ago and just changed out the piston and it ran like new. There was not even any scoring on the cylinder walls from the broken piston skirt. Wile I was in there I did all of the rings and rod bearings changed the head gasket, then sold it and it is still running today. These engines are very hard to kill. It might be worth looking at just changing the piston, rings and rod bearings and keep driving.

andrewmp6

I believe you need a 4.0 from 97-99,As far as mileage we have members over 300k and i have read about one xj with 612k on it but the guy bought it new and took super care of it.

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)

t.mcginley.jr

Wow sounds like I won't need to worry about mileage so much as long as it was taken care of. The guy wants $300 firm for the 96 GC engine, which seems like a good deal to me. Local junkyards want $500+ for 200k+ mileage ones.

I haven't pulled anything apart on my engine yet, but it could very well be rod knock and not a broken skirt. Even if there wasn't any internal damage, I have the troublesome 0331 head which will probably crack at some point. One of the receipts in the glovebox already mentioned cylinder head "problems", but no what they did to correct them. So at the very least I would need to rebuild this engine and find either an earlier head or a TUPY one. Just looking for a simple swap right now, but I will keep this one and pull it apart if I go this route.

Thanks for the info guys!

Also, can I bolt my 2000 intake manifold to the older 96 head? I know the exhaust is totally different but I thought I remember reading that the intake ports are the same, and that later models flow a little better.

t.mcginley.jr

Ignore that last question about bolting up the newer style 2000 intake to the older style head, I just read this writeup:

http://mallcrawlin.com/forum/showthr...-DYNO-NUMBERS!

Apparently some nice gains are made to the wheels with the newer style manifold. Since the 2000 model engine had more power than the 96, I'll probably end up with around the same amount of stock power after the swap.