Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

Lifters or Rod

Thread Tools
 
Search this Thread
 
Old 12-20-2010, 02:05 PM
  #1  
Newbie
Thread Starter
 
Crystal's Avatar
 
Join Date: Dec 2010
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee
Default Lifters or Rod

I have a 2000 jeep grand cherokee 4.0L, making a ticking/knocking sound , I am trying to figure out if its the lifters or a rod bearing out. I've taking it to one machanic and he says Rod because it sound like the sound is coming from the bottom of the motor, but I know in the 4.0L that the Lifters are in the middle of the motor so that could sound like the bottom??, my husband tried to push down on the valves but said he couldn't tell if that made a difference so I am hoping some one can give me a way to test it out so I can make the choice between just changing the lifters or having my motor rebuilt. Thanks
Old 12-20-2010, 02:10 PM
  #2  
CF Veteran
 
TheJerm's Avatar
 
Join Date: Jun 2010
Location: Flint/Asheville
Posts: 2,501
Likes: 0
Received 4 Likes on 4 Posts
Year: 1995
Model: Cherokee
Engine: 4.0 HO
Default

How many miles on it?

Could be cracked flex plate, loose torque converter bolts, rod bearings, or the valve train not torqued correctly. I would inspect in that order and you dont have to overhaul the whole engine for rod bearings, you can leave the crank in the motor while its in the jeep with the head still on if it comes to that, i doubt it but ive done it that way
Old 12-20-2010, 02:13 PM
  #3  
Newbie
Thread Starter
 
Crystal's Avatar
 
Join Date: Dec 2010
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee
Default

185k miles on it.
Old 12-20-2010, 02:22 PM
  #4  
"CF Moderator"
 
TrekkerJmm's Avatar
 
Join Date: Sep 2008
Location: N.J. Shore Area
Posts: 3,045
Likes: 0
Received 2 Likes on 2 Posts
Year: 1994
Model: Cherokee
Engine: l6 HO
Default

Whats the oil pressure at? ...Tj
Old 12-20-2010, 02:23 PM
  #5  
"CF Moderator"
 
TrekkerJmm's Avatar
 
Join Date: Sep 2008
Location: N.J. Shore Area
Posts: 3,045
Likes: 0
Received 2 Likes on 2 Posts
Year: 1994
Model: Cherokee
Engine: l6 HO
Default

O and welcome to CF from Tj...
Old 12-20-2010, 02:31 PM
  #6  
Senior Member
 
letsgomuddin's Avatar
 
Join Date: Nov 2009
Location: Lowell, MI
Posts: 774
Received 7 Likes on 4 Posts
Year: 2001
Model: Cherokee (XJ)
Engine: 4.0
Default

185k, prolly the lifters then. They start rattling around 160k. If the oil pressure's good, thats prolly it
Old 12-20-2010, 02:36 PM
  #7  
Newbie
 
UserID6095's Avatar
 
Join Date: May 2009
Posts: 3
Likes: 0
Received 2 Likes on 2 Posts
Model: Cherokee
Default

Does it increase with rpm? Does it go away once warm?
Old 12-20-2010, 02:36 PM
  #8  
CF Veteran
 
TheJerm's Avatar
 
Join Date: Jun 2010
Location: Flint/Asheville
Posts: 2,501
Likes: 0
Received 4 Likes on 4 Posts
Year: 1995
Model: Cherokee
Engine: 4.0 HO
Default

Originally Posted by letsgomuddin
185k, prolly the lifters then. They start rattling around 160k. If the oil pressure's good, thats prolly it
where'd you hear they start rattling around 160k? I've had 1/3 jeeps make noise under 190K, my current has 212K and is the quietest 4.0 ive ever seen/heard (probably due to sludge). While it may be annoying it doesnt mean the motor will crap out on you.
Old 12-20-2010, 02:50 PM
  #9  
Newbie
Thread Starter
 
Crystal's Avatar
 
Join Date: Dec 2010
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee
Default

Originally Posted by TrekkerJmm
Whats the oil pressure at? ...Tj
the oil pressure stays normal and the sound quites a little after its warmed up, but the ticking accelerates with the throttle...
Old 12-20-2010, 02:51 PM
  #10  
Newbie
Thread Starter
 
Crystal's Avatar
 
Join Date: Dec 2010
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee
Default

Originally Posted by trs80
Does it increase with rpm? Does it go away once warm?

yeah increases with throttle and only quites when warm never stops.
Old 12-20-2010, 04:22 PM
  #11  
Newbie
 
UserID6095's Avatar
 
Join Date: May 2009
Posts: 3
Likes: 0
Received 2 Likes on 2 Posts
Model: Cherokee
Default

Sounds like a rod bearing to me. Check the flex plate bolts as mentioned, they are known to loosen up over time and can create a noise similar to rod bearings.

I would drive it 'till the bottom end comes apart and then swap a used or rebuilt engine in. Only down side is if a rod lets go it will make a nice size hole in the block. Used engines are cheap on Craigslist.
Old 12-20-2010, 04:52 PM
  #12  
CF Veteran
 
TheJerm's Avatar
 
Join Date: Jun 2010
Location: Flint/Asheville
Posts: 2,501
Likes: 0
Received 4 Likes on 4 Posts
Year: 1995
Model: Cherokee
Engine: 4.0 HO
Default

Broken rods dont "always" put a hole in the side of the block, it depends on where the rod broke. Fixed a YJ with a hydrolocked motor that broke 1 rod and bent another in 3 planes. I couldnt believe it ran it the bent rod as well as it did after we dropped in another piston and rod.
Old 12-20-2010, 07:08 PM
  #13  
Newbie
 
UserID6095's Avatar
 
Join Date: May 2009
Posts: 3
Likes: 0
Received 2 Likes on 2 Posts
Model: Cherokee
Default

Originally Posted by TheJerm
Broken rods dont "always" put a hole in the side of the block, it depends on where the rod broke. Fixed a YJ with a hydrolocked motor that broke 1 rod and bent another in 3 planes. I couldnt believe it ran it the bent rod as well as it did after we dropped in another piston and rod.

Semantics.
Old 12-20-2010, 07:32 PM
  #14  
Seasoned Member
 
N8-96XJ's Avatar
 
Join Date: Aug 2010
Location: Galax Virginia
Posts: 298
Likes: 0
Received 0 Likes on 0 Posts
Year: 1996
Model: Cherokee
Engine: 4.0
Default

Welcome to CF!
I hate noises... Check Youtube. Search "Jeep Knock" Every noise you can imagine is on there. It is a really good comparison as far as narrowing it down. Hope it's nothing serious. Good luck!
Old 12-20-2010, 09:30 PM
  #15  
CF Veteran
 
89whiteXJ's Avatar
 
Join Date: Apr 2009
Location: Jacksonville, FL
Posts: 1,097
Likes: 0
Received 1 Like on 1 Post
Year: 1989
Model: Cherokee
Engine: 4.0L
Default

My sister is having a similar problem with her 2000 xj. She was told it was rod bearing so I changed them for her. I also did the oil pump while there. But it still knocks or ticks. We did not do the main bearings. My sisters motor has 184k too. The sound on hers sounds like its in the bottom at the front. Like near piston 2


Quick Reply: Lifters or Rod



All times are GMT -5. The time now is 07:35 AM.