I just bought a 2000 sport with 4.0 and 127000 miles, ran great for about a week. i changed the oil and put in lucas oil stabilizer. then i got a very loud knock. brought it to my friends shop and he said i have a spun rod bearing and cracked cylinder head. what do you guys think i should do? thanks
Not 100% sure but I would imagine 97-02 i think. But it would probly be cheaper to pull the whole motor now that I think about it especially if you've never rebuilt an engine. getting a used head it will need to be machined 80-120$ plus gasket 50-100$ plus your rods if it were me and I wanted to keep the 4.0 I'd replace the whole engine. There are alot of grand Cherokees with 4.0s in our local junkyard.
if i decide to fix it myself what year heads can i use on my 00 block?
I would shop around for a new head. IIRC I saw some in q-tec for about 450ish with all the goods installed on them. All you would basically have to do is pop the old head and put the new one on. No muss not fuss.
Never get between a man and his Jeep - Stacey David.
2000 4.0L have the 0331 head casting which is very well known for cracking. Mine went the other day, just turned 80k miles. I think my PO thought it was a head gasket and put a bunch of sealer in the coolant and patched it up instead of fixing it correctly.
Cracked head isn't a huge deal, you can get a head from Alabama Cylinder head for less than $500 shipped to your door, torque it down and hit the road. If the rod bearing truly is bad, then you need a rebuild. I think a lot of people jump to the bad rod bearing a little too quickly. Do some research, make sure you got the correct diagnosis before making any decisions. Motor swaps are a pain in the ***, then again so is a rebuild.