Jeep Wrangler Forum banner

knocking noise after lift installed

16K views 62 replies 16 participants last post by  jgalvar 
#1 ·
Installed a zone 4.25 combo on my 99 TJ and getting a knocking like sound when first starting off for about 2 seconds than goes away. It seems to be coming from the TC area. I added a few washer and dropped the TC about 1/4 inch and still the same noise. It does not do it in reverse or if I take off in 4wd. I get no other vibrations or noises when driving....I am not convinced it is drive train related, Any suggestions or remedies.

Thanks,

Dan
 
#2 ·
Dan....I just installed a Zone 4.25 combo lift and am having that exact problem also. I also installed the transfer case drop about 1/2 inch (but I broke off one of the bolts holding on the transfer case to the skid).

Anyway.....just like you I get it when starting from a stop only for a few seconds and goes away.....and it wont do it in 4wd.

Have you gotten anywhere with this at all???
 
#4 ·
Can't speak for Dan...but yes I installed the relocation bracket for the linkage. Tried adjusting the linkage as best as I could yesterday and today. I thought we had it worked out.... drove it a few miles and then went into reverse a bit...when I came back out it was there again. And pretty bad. It sure does sound pretty awful (as it not normal) and you can feel in the gas pedal and under the floor. Funny thing is standing outside the jeep you can't hear anything.

So you think it's that linkage still??? I'm not sure what else to do with it at this point.

Do you think it has anything to do with one of the bolts breaking off holding the transfer case on the skid?? Would that be causing it. I didn't do anything with it I thought the 3 remaining bolts would hold it.

Ideas??? Or back to the linkage???
 
#5 ·
Could be the missing bolt. You can manually shift to 2 hi with the linkage removed to verify. Removing and reinstalling linkage can be a pain though. There is a TSB for knocking linkage too you can look into. Another thing you can check would be the tunnel bushings. I don't know why Chrysler designed though things like they did, but they wear out or get messed up when removing them. That's why I just went with a cable shifter.
 
#8 ·
BLK....read over the TSB (thank you). It sounds promising...but I'm not sure if it would work with the new Zone relocation bracket. Once the lift is on you have to lower that bracket. When I first looked at it my I didn't know if the torque shaft should be touching the body bracket or not...but I assume Zone knows what's going on. (Also I had to do the TC lowering..so I don't know if that threw it off also).

Anyway....tonight I took it all apart and put it back together (couldn't even move adjustable rod at first it was so rusted). But after freeing it up still got the knocking.

Do you think with the Zone lift and the TC lowering it would be worth still buying the parts for the TSP???
 
#11 ·
Dan...just an update for you.

I worked on the issue again this afternoon. I re-adjusted the linkage (again)...this time way shorter (as in I probably have about 2" sticking out past the locking bolt). I could never even get it that short before so I thought I could try it. And it shifted into all the gears better than I had gotten it to before.

The noise however was still present....but not nearly as bad!! So it went in the right direction.

The funny thing is that I also put my spare back on today also....so now I am wondering if just adding the extra weight to the rear was part of it. Maybe I need to lower the transfer case even further and that will get rid of the issue. Going to add some sand bags tomorrow and see if that makes a difference. If not...maybe even shortening the linkage more if I can figure out a way to get it shorter.

Anyway.....food for thought. Have you gotten anywhere on yours??
 
#12 · (Edited)
Dan....another update.

I kind of threw my hands up on this thing.

Tried putting 280 lbs of sand bags in rear just to see if maybe I didn't put enough drop on the TC and maybe that's causing it....no difference in the noise.

Then (yet again) re-adjusted the TC linkage. This time to its max length....I can't get it any longer.....and still nothing!! The damn knocking is still there and driving me crazy. If I totally baby the gas and just let it slowly roll in speed it doesn't happen...but if i get on the gas at all it's there.

U get anywhere on yours??

Going to try a mechanic tomorrow...I don't have anymore ideas!!
 
#13 ·
Nope nothing, same thing if I ease out on the gas it doesn't knock. I tried the TC drop with some washers and nothing...actually It got worse. I have also extended my TC linkage to its max, looks like we are on the same page. I think I will stop by a jeep dealership and buy that linkage kit for 20 bucks it seems to make sense. I have come to a conclusion it is more annoying than harmful to the TJ...I hope. I will let you know if the kit worked, cheers and good luck brother.
 
#14 ·
Yeah let me know what happens with that kit.....my mechanic friend didn't have time to look at it today...told me to bring it by in a few days and he will throw it on the rack. He said it sounds just like something is rubbing that shouldn't be....but he wanted to look at it before guessing. I was hesitating on the kit.......I think I will see how you do with it. Keep me posted man!!!
 
#15 ·
OrdieCPO, Jamie,....

Hey guys, just read your thread and what you guys have is exactly what I've got now. It started with mine right after I put my zone 4.25 combo lift on my 98. I'm thinking that if all three of us are having the same problem after installing this kit, we can't be the only ones. I think I will be calling zone tomorrow to see what they say.
 
#16 ·
Just talked to zone offroad and they said that they don't know of any specific thing that would be causing this. They did tell me however that they have a call into their engineer that is running the same lift on his. Maybe he can come up with some answers. The person I was talking to said to put weight in the rear, but I told them that one of you guys had already done this with no luck. So I guess we'll see if they can come up with anything. If I hear from them, I will post immediately.
 
#17 ·
All of that work.... but no one decided to actually lower the TC Skid a little more?

I only have a 2.5" lift and experienced exactly what you guys are. Solution, lower the skid plate or install an SYE.

Throw up some pics of your drive lines, or save the time and drop it about an inch total and take it for a spin. Don't forget to loosen the 4 bolts in the middle so it can slide front/rear as needed while you lower it then tighten them back up. If the problem goes away, lose some washers, see how much drop you actually need.
 
#20 ·
I suggest that you guys that are experiencing this noise remove your skid and inspect your tc mount. If it is cracked and torn on one side, it can let the tc move vertically under load, then come back down. I helped J4J put his lift in and he just informed me that he found his mount was torn. He hasn't replaced it yet, but I would bet $'s to donuts that's where the issue is.
 
#21 ·
Hey waterdog, the tc mount is in. Just waitin for you to come through on the new skid :thumb:. Once everything is put back in its rightful place, I'll repost the findings. I'll leave the skid spacers out first and see if the tc mount was the real culprit.
 
#25 ·
Hopefully I can reserve one day this weekend to troubleshoot this knocking. I am going to inspect everything for any obvious damage due to metal on metal contact. Agreed that the MML is "suppose" to eliminate the dropped TC, a lot of people are using this set up without the TC drop or a SYE without issues. I will post pics and findings so we can figure this out.
 
#30 ·
#31 ·
I do have to come clean and admit to twisting off one of the mounting studs when I installed the new mount. So I will be putting the replacement on tomorrow. Autozone was cool enough to just give me a new one. The install literally takes 10-20 min. Good Luck and Godspeed!
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top