4.0 motor knock - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > YJ Jeep Wrangler Forum > YJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 04-07-2013, 10:13 PM   #1
Newb
 
1988jeeper's Avatar
 
Join Date: Nov 2012
Posts: 2
4.0 motor knock

Ok this is my first time posting. So I got a yj that I purchased about 2 months ago the oil was really black but I ran it like that for about two weeks then I took it to a quik lube because it was still cold out I'm guessing they used cheap oil and 10w30 well after I had that done after it fully warmed up it would start to tick or knock sounded like top end and the oil would be just like water very liquidly so I did an oil change myself and used 5w40 I believe amd that worked fine for about 3 weeks now it starts fine but when it fully heats up it starts to knock pretty loud can someone help me out like what oil should I use or other products sorry for writing a book for you guys . Thanks

1988jeeper is offline   Quote Quick Reply
Old 04-07-2013, 11:21 PM   #2
Jeeper
 
Tyler92yj's Avatar
 
Join Date: Sep 2012
Location: Corpus Christi
Posts: 480
add some lucas upper cylinder lube

__________________
4.0, 4.10 gears,8.8 with lsd, spartan up front, 4 inch rc, 5/8 boom shackles, 1 inch body lift, 33x12.50 toyo mts
Tyler92yj is offline   Quote Quick Reply
Old 04-08-2013, 09:34 AM   #3
President, ThumbJeeps

WF Supporting Member
 
sevenservices's Avatar
 
Join Date: Sep 2009
Location: Mid-Michigan/Thumb
Posts: 3,939
Instead of running a 5 or 10-40 then adding treatments, do the opposite. Run a 5-20 and don't add thickeners (oil treatments)

The thinner the oil, the faster it will get to the top end.

The loudest my 4.0 ever rattled was after adding lucas... Thinner oil will do wonders, I learned this by having to wait a month after an oil change for it to quiet down. Then, I tried 5-20 and the thinner oil kept it quieter right out of the gate for sure.

A lot of people say to add oil treatments for loud engines not realizing that a lot of time the problem is that the oil is already to thick. By adding treatments your thickening it even worse. 3 years ago, I'd have said to add lucas. Then, I learned that it made my engine a lot louder whenever I would try it.
__________________
-Chris
President, ThumbJeeps
CB Callsign "AirForce One"


1994 Wrangler YJ I6 4.0 H/O Auto 3 spd. 4" RC (33x12.5) (15x8) 3:54 Gears
sevenservices is offline   Quote Quick Reply
Old 04-08-2013, 02:42 PM   #4
Jeeper
 
Join Date: Jan 2010
Location: Las Cruces, NM
Posts: 2,291
So is the knock or tapping coming from the valve train....is so could be a dirty lifter..
__________________
2013 WRANGLER SPORT 2 DR., V-6 ,AUTO,HARD TOP
(Sold)1994 Jeep Wrangler 2.5L, Bestop top
/w steel half door and slider windows
5 speed, 2.5" lift, 31" tires,rack lights
Garyk is offline   Quote Quick Reply
Old 04-08-2013, 08:21 PM   #5
Newb
 
1988jeeper's Avatar
 
Join Date: Nov 2012
Posts: 2
Thanks guys ill try thinner oil and see how that goes
1988jeeper is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may 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




» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 11:33 AM.



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