Help! Knocking noise when engine first comes under load - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > General Technical Discussions > Engines & Drivetrain > Help! Knocking noise when engine first comes under load

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineFS: Wrangler RGB Multicolor Fog Light LEDs: Awesome EffectSavvy Aluminum Gas Tank Skid

Reply
Unread 07-28-2013, 04:30 PM   #1
ryanataylor87
Registered User
2001 TJ Wrangler 
 
Join Date: Jul 2013
Location: The Colony, Texas
Posts: 3
Help! Knocking noise when engine first comes under load

I need some help from fellow jeepers! I have a 2001 Wrangler TJ 4.0L manual 5 speed, when I accelerate from a stop and the engine first comes under load I am hearing a knocking noise, maybe 4 to 5 hits, that goes away as I accelerate, but I can feel a lot of shaking through the floor and the shifter. The sound seems to come from either the transmission or rear of the engine.

To try and fix this I have tried several things:
Replace transmission mount (stock one was cracked)
Inspected engine mounts, both are in good shape
Replace all u joints in front and rear driveshaft (5 total)
Recently changed all fluids:
Transmission, transfer case, engine oil

At this point I am out of ideas and engines aren't really my area of expertise. It's this some kind of drive line issue still, or something in the engine or transmission?

My jeep isn't a daily driver, so I haven't had to break down and take it to a mechanic yet. I like to fix things myself and I learn quickly so I thought I would ask around before taking it in. Thanks for any help you can offer!

ryanataylor87 is offline   Reply With Quote
Unread 07-28-2013, 11:52 PM   #2
Holder350
Web Wheeler
 
Holder350's Avatar
1995 XJ Cherokee 
 
Join Date: Oct 2007
Location: Whitesburg, Tennessee
Posts: 5,260
Lift up on the transfer case shifter when it does it. If it goes away then you need new bushings for the transfer case linkage Zbar.

You can buy a repair kit from the dealer or from several online sources. Seen them on eBay also.

http://www.4wheelparts.com/Drivetrai...16&t_pt=101386


Sent from my phone
__________________
95' XJ Country - Stock Skids - D30/D35 Limited Slip - 3" Lift - 31x10.50R15 - 4.0 HO - AX15 - NP231

98' XJ Classic - D30/C8.25 - 4.5" RC Lift - 33x12.50R15 - 4.0 HO - AW4 - NP231
Quote:
Originally Posted by Azzy View Post
You can tell the character of a person in how they treat someone who can do nothing for them.
Holder350 is offline   Reply With Quote
Unread 07-30-2013, 01:01 PM   #3
ryanataylor87
Registered User
2001 TJ Wrangler 
 
Join Date: Jul 2013
Location: The Colony, Texas
Posts: 3
Quote:
Originally Posted by Holder350 View Post
Lift up on the transfer case shifter when it does it. If it goes away then you need new bushings for the transfer case linkage Zbar.
Thanks for the suggestion, I will give that a try when I get home tonight and post the results.
ryanataylor87 is offline   Reply With Quote
Unread 07-30-2013, 08:32 PM   #4
ryanataylor87
Registered User
2001 TJ Wrangler 
 
Join Date: Jul 2013
Location: The Colony, Texas
Posts: 3
Quote:
Originally Posted by Holder350 View Post
Lift up on the transfer case shifter when it does it. If it goes away then you need new bushings for the transfer case linkage Zbar.
Well that did it, thanks for the advice! I knew you guys could help me, but I honestly thought it would take a little more trial and error if you know what I mean. Thanks for link as well, that is very helpful.
ryanataylor87 is offline   Reply With Quote
Unread 07-30-2013, 08:40 PM   #5
Holder350
Web Wheeler
 
Holder350's Avatar
1995 XJ Cherokee 
 
Join Date: Oct 2007
Location: Whitesburg, Tennessee
Posts: 5,260
Quite welcome, my jeep has the same issue...and I have he repair kit in the toolbox....I have just yet to install it....I'll get to I one of these years....

Sent from my phone
__________________
95' XJ Country - Stock Skids - D30/D35 Limited Slip - 3" Lift - 31x10.50R15 - 4.0 HO - AX15 - NP231

98' XJ Classic - D30/C8.25 - 4.5" RC Lift - 33x12.50R15 - 4.0 HO - AW4 - NP231
Quote:
Originally Posted by Azzy View Post
You can tell the character of a person in how they treat someone who can do nothing for them.
Holder350 is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.