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lgoss5127 05-16-2013 11:30 PM

98 tj knocking on takeoff
I have a 98 TJ with 109k on it. Lifted 3" with 33's. i noticed when I take off in first it knocks 3 to 4 times. The faster I let out the clutch the louder it is. If I let it out slow it won't do it. Does anyone have any idea of what it could be? I'm new to the jeep scene so I'm not sure of what it could be. It just doesn't sound like it should be there.

somis 05-17-2013 03:23 AM

67 Attachment(s)
There are lots of possibilities. Much to vague. I'm assuming its coming from somewhere in the driveline. (MOTOR, TRANSMISSION, TRANSFERCASE, REAR AXLE)
But I could be wrong. Does it sound like a metal on metal connection?

If its possible, find a shop with an actual lift and let them use a stethoscope to pin-point the issue. From there I am sure they will be able to diagnose your issue.

I'd tell you to put it on jackstands and try this yourself with a buddy but I dont want to be responsible for a death. Be careful if you do try that.

UFOtestpilot 05-17-2013 03:27 AM

Sounds like the transfer case linkage knock.

UFOtestpilot 05-17-2013 03:32 AM

It may be the way your jeep was lifted as well, you may be missing a component for your linkage. If you've got the money and it turns out to be t-case linkage knock, get the Novak cable and call it a day. If you have everything there but the bushing at the torque rid knocks and rattles when you wiggle the heck out if it, then this could very well be your issue.

GoldenSahara00 05-17-2013 04:02 AM

Could be the exhaust.

UFOtestpilot 05-17-2013 08:00 AM


Originally Posted by GoldenSahara00 (Post 3764538)
Could be the exhaust.

lol, that's definitely a good place to start. Having gone through the laundry list of possibilities for my mystery noise before I found it, I often forget that the cause of mine won't be the cause of everyone's.

GoldenSahara00 05-17-2013 08:40 AM

I had a knock from the old linkage before I replaced mine as well, just throwing out some more. I currently have 1 broken hanger and 1 loose hanger on my exhaust, and the tip just contacts the hitch and makes a noise like described on hard throttle.

lgoss5127 05-17-2013 12:59 PM

Thanks guys. I'm gonna do a very thorough inspection of it today when I get off work. Ill let you know what I find!

lgoss5127 05-17-2013 01:53 PM

well its not the exhaust, i shook everything down there and everything seems to be on there pretty tight. i'm starting to think it might be a the transfer case linkage and im kinda leaning toward the novak cable. does anyone have that installed on theirs? is it worth the money?

GoldenSahara00 05-17-2013 02:10 PM

I do, and it is. Because it lets you use your 4wd reliably. lol. And I can adjust it with any changes I make in the future.

SuicideSaints 05-17-2013 02:38 PM

I had a similar sound, 3-4 knocks when first taking off. If I went real slow it didn't do it. It ended up being loose control arms. The first time I tried to find it the control arms seemed fine then I put my jeep on level ground with no e brake and tried again. I found two loose control arms. Make sure you check both sides of each arm.

s14sh3r 05-17-2013 02:55 PM

Mine does it and it's the transfer case linkage. I sprayed the hell out of the bushing it rides in with white lithium grease and it's stopped it for now.

lgoss5127 05-17-2013 02:58 PM

ill have to re-check my control arms. if thats not it ill the white lithium lol wd-40 has white lithium dont they?

s14sh3r 05-17-2013 03:18 PM

Yes, wd-40 makes a spray lithium grease. I don't have a picture to show you where the knocking is coming from and it's kind of hard to see because of the skid plate. There is a rod that runs side to side. It fits into a bushing and bracket next to the body. I can grab that rod and move it up and down and it makes the same noise it does when I take off. I'll replace the bushing one of these days and fix it for good.

UFOtestpilot 05-17-2013 05:33 PM

I would have done the Novak cable now, but I couldn't spare the funds at the moment and I couldn't stand the knocking any longer. I will get the cable in the long run though.

timboburks 05-17-2013 06:36 PM

Mine is a 2000 auto. Just had it lifted a few weeks ago, and had something similar. Turned out to be the transmission mounts were rotten. Don't really know anything about it, but the guy I took it to said he crawled under it, grabbed the driveshaft and shook on it, and could see the transmission moving.

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