3.8L lower end knocking? - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > JK Jeep Wrangler Forum > JK General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 11-14-2010, 09:55 PM   #1
Jeeper
 
Sierra8's Avatar
 
Join Date: Apr 2010
Posts: 147
3.8L lower end knocking?

I have a very faint knocking sound after my Jeep warms up. It is audible without any load on the motor up til about 2k rpm and then goes away. The knock isn't very loud but is definitely there. I've removed the serpentine belt temporarily for a few seconds to make sure it wasn't any of the accessories and the knock is still there.

I bought my Jeep used at around 44k and have about 53k on it now. The knock hasn't gotten worse but I think it's always been there since I've owned it. Is this maybe piston slap I'm hearing or something else? I also have the clutch pushed down and it doesn't seem like anything with the clutch assembly spinning in neutral. Anyone hear this too or is this maybe something I should worry about? I have an extended warranty up to 125k so I'm not terribly freaked out but I'd like to figure out what's generating the noise.

Sierra8 is offline   Quote
Old 11-14-2010, 10:05 PM   #2
Member
 
Join Date: Mar 2009
Location: Upstate/Eastern NY
Posts: 1,960
Send a message via AIM to thaduke2003
I would DEFINITELY bring it in to get checked out. If it's major, I'd want it fixed BEFORE you get stranded with a popped engine! Mark W.

thaduke2003 is offline   Quote
Old 11-15-2010, 05:58 AM   #3
Jeeper
 
muddinjk's Avatar
 
Join Date: Aug 2010
Posts: 179
i have 2 guesses here

either you have had a poorly maintained jeep and there so much sludge built up in the engine that ur not getting enough oil, easy to check take rocker cover off and all check, replace gasket doesnt take to long or

you did the bottom end which means take the 3.8 out throw away and drop a 350 in it
__________________
2007 Jeep Wrangler 2DR Sport
33x12.5x16 Mickey Thompson MTZ
3 Inch Lift-Synergy Springs, Fox Shocks, Teraflex Lower Control Arms, Fox steering dampener
Arb Winch Bullbar with 9500lb Winch(dynamo rope)
Synergy chromolly tie rod and panhard rod
muddinjk is offline   Quote
Old 11-15-2010, 07:02 AM   #4
Jeeper
 
Hilldweller's Avatar
 
Join Date: Apr 2008
Posts: 4,187
Quote:
Originally Posted by thaduke2003 View Post
I would DEFINITELY bring it in to get checked out.
There are too many things it could be for an internet diagnosis. From totally benign to catastrophic.
Listen to the Duke and have a trusted mechanic give it a look.

If you're going to drop the oil pan to look for sludge, put one of these on or a skid.

Good luck
__________________
Gone camping,
Bill

Hilldweller is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
??? REPLACING LOWER IDLER PULLEY ON 92 YJ w/AC whiteoaks YJ Tech Forum 3 10-08-2013 02:40 PM
still knocking please help spyjeep0520 TJ Tech Forum 0 07-01-2010 09:51 PM
Installing lower control arms. Help Triple88a TJ Tech Forum 4 09-30-2007 09:23 PM
Engine knocking stabs05 TJ Tech Forum 8 08-16-2007 08:08 PM



Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 01:48 PM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC