I recently developed a know on my xj. ive checked all push rods,lifters, etc. as of this moment i am ready to pull the engine and break into it. im just curious about what you guys may think it is? it does sound like its towards the rear cylinders, my guess is a cracked piston skirt. any ideas?

 

Since you have an automatic transmission, start with doing this before tearing apart the engine:
https://www.cherokeeforum.com/f51/ho...ocking-125547/

It takes an hour if you really take your time.

How's your oil pressure and what brand oil filter are you running?

 

Ive already checked all those bolts. And the knock is still there. Iknow its inside the block somewhere. Im on my way out the door now to go pull the engine. Ill post up pics of the block and internals when its all out. Might as well take the time to do a full rebuild since its gonna be out...

 

Cracked ring gear ?

 

Well ive been stuck on one bolt from the tranny since the last post. Theres just no way i can get to it. Its the one you have to use the E socket on. On the passenger side. Thinking of just pullin the tranny with the engine... I know its gonna be more work but i think it will be easier then fighting with one bolt.

 

Well engine is finally out. Have the pan off and its definately cylinder number 4. Piston is rocking back and forth slappin the wall which i believe was causing the knock....hopefully thats the only problem

 

I had this problem and it broke the piston skirt which I had to replace. Now i have another knock.... oh boy

 

Heres what i found in the pan...

 

Heres what i found in the oil pan....

 

Hey thats exactly what i found in mine

 

So it turned out being exactlt what i thought.... Here it is

 

Itwont show the picture ill have to post it later. But it is a cracked piston

 

Itll prob look somethin like mine