Loud noise from the front differential during a turn

dchew

Caught the Bug
Took Oso on his maiden voyage yesterday and it wasn't good. When in an extended tight turn for maybe 10 feet or so (like pulling out of a driveway) there is a loud clank from the front end then the Jeep wants to pull to one side. It feels almost like it is in 4wd on pavement. Then it works itself out and drives fine until the next extended tight turn. This all happens while in 2wd. Jeep is a 2013 JKUR manual trans.

Changing the gears was the one thing we didn't do ourselves in this build. We sent the housings off to have that done (4.88's installed). :(

Here are all the possibilities I think:

1. Steering: Installed a PSC ram, new gearbox and pump. I really don't think this is the problem because if you steer lock to lock without moving the Jeep there are no problems. I can turn the 37's in place with my pinky.

2. Axle shafts: Installed RCV shafts in the front. That install was pretty straight forward, but perhaps something is binding?

3. Gears and or rubi locker: This is what I think is at the top of the list. I've never driven on pavement with the locker engaged. What would happen if that was done in a turn? Would the tires just howl and slip or would the differential give?

Another big clue that I should have noticed: When torquing the wheel spacers with the jeep on a lift, I did not need someone to hold the other axle to keep it from spinning, but I did on the rear.

So here are some things I'm thinking of doing:

  • Lift up the jeep and run it while on the lift. Put it in gear, turn the wheels and see what happens
  • Try locking and unlocking the differential. I have not tried that yet for fear of implosion…?
  • Go in the corner crying and sucking my thumb

Any other suggestions?

Dave
 

mn jk jeeper

New member
have someone else drive the jeep and u get out too look and see of you can spot any movement in the cv's or hear where it may be coming from
 

dchew

Caught the Bug
have someone else drive the jeep and u get out too look and see of you can spot any movement in the cv's or hear where it may be coming from

Yeah we tried to do that a few times. There is nothing external that we can see. We are going to try again today though. I'm sure I am quickly trashing something each time I do it!

Dave
 

wayoflife

Administrator
Staff member
So, did I read correctly that with your front tires in the air, you were actually able to tighten your wheel spacer lug nuts without having someone step on the brakes or brace the rotor??
 

wayoflife

Administrator
Staff member
Yeah. I'm a dumb A**

Should have registered alarm bells all over, eh??

LOL!! Didn't say that but, I might refrain from driving anymore until you can get your Jeep back up in the air and spend some time tracking this problem down.
 

dchew

Caught the Bug
Well I should clarify that I did have the DS held into position at the time so it would not spin. But nothing holding the other wheel.
 

dchew

Caught the Bug
Talked to the guy that did the gears and he thought it sounded like the axle shafts were pressing in on the differential as if they were too long. Hard to believe but since I installed them and it was the first set I've ever done, we decided to pull the RCV shafts and put the stock shafts back in. But it was pouring rain so we didn't drive it.

Could not get it up on the lift because we had to do a brake job for a family in a bit of financial distress, so we had a 2003 Trailblazer up there. Turns out it needs new backing plates which means pulling the rear axles, and those are clipped inside the differential. So as usual a simple one evening job turns into two. Hopefully more info tomorrow.

Dave
 

dchew

Caught the Bug
Got it back up on the lift. Pulled the front diff cover, yuk. The R&P look fine, but the locker looks bad, and there are metal shavings everywhere. This thing was driven a total of about 1/2 mile. So the question now is what do I need to replace? The R&P look pretty good, but I can only imaging what the spider gears look like inside, and I bet the locker is trashed. I don't know anything about lockers; not sure if I should have it replaced with stock or should I put an ARB in there. Any suggestions? These are not the best pics because my hands were shaking from my uncontrolled sobbing. But here you go:

See the plate with the holes in it just to the left of the plug connector. It is peeled up away from that clutch (or whatever it is) because of a head in the back that it is riding on. When you spin a wheel or the DS that plate moves up, down and around while making all sorts of unpleasant noises. And, when you spin the driver side wheel forward the passenger side spins forward too as if it is locked. But that diff has never been locked. I'm guessing when it locks, that clutch (?) with the electrical connection moves to the left and engages. But that bolt in the back has put it in limbo - sort of half engaged. Then under steering load it would bang in and out of locking. Does any of that make sense?
IMG_0546.jpg

Here is that head in the back, right in front of the pinion. Can't tell if that is a bolt or something else...?
IMG_0547.jpg

Ugly shavings
IMG_0549.jpg

More ugly chunks in the bottom.
IMG_0550.jpg

Ugh.

Dave
 
Last edited:

Philip *AZ*

Banned
Man, thats a bummer! I know how you feel though. When I had my '98 GMC I took it to a shop to have 5:13's installed to help roll my 37's. shop called me to go get it. I was so excited! My buddy takes me over, talk to the installer about how bad ass the 5:13's were and how much of a difference it was. I was stoked man. Hop in, back out and drive away like normal ( aware of the break in period). Get about a half mile down the road doin about 40-45 and BANG!! The tires locked up. Tires squealin, truck shakin, and the worst sound ever comin from the rear end. Called the shop and told them to come get my truck. Back at the shop, he pulled the diff cover right there and it looked like legos falling out. I wanted to cry man..
Sucks you are having to deal with this. I hope you get it right, quickly.. (Sorry for the long hi jack)


Paratroopers stay up longer!
 

dchew

Caught the Bug
Thanks for the moral support! I did some more searching and found a post on JK-forum about this. That head in the back is the sensor, and it is stuck open. Probably bent, so it is holding the locker gears half engaged. They are mashing each other to death in that position.

Dave
 

wayoflife

Administrator
Staff member
That head is the locker sensor and it NEEDS to be on the otherside of the dog clutch (rookie mistake). In this position, your locker light should have been flashing - was it? Having said that, you should have been able to drive just fine with the plunger in this position (or at least, I have known other to be able to) and that alone shouldn't explain all the metal you are seeing. Something else might still be off.
 

dchew

Caught the Bug
I think in its current position the sensor is pushing the dog clutch just enough to partially engage the locker and these locker gears are what are mashing. Would that be possible?
 

dchew

Caught the Bug
Eddie,
The light was flashing when I tried to engage it from inside the cab, but when I disengaged it the light was off and stayed off.
 

wayoflife

Administrator
Staff member
I think in its current position the sensor is pushing the dog clutch just enough to partially engage the locker and these locker gears are what are mashing. Would that be possible?

I doubt it but, it'd be hard for me to say for sure. I suppose it is possible - certainly, a lot of that metal could be from the tooth closest to the plunger getting clearanced.

Eddie,
The light was flashing when I tried to engage it from inside the cab, but when I disengaged it the light was off and stayed off.

Yeah, that should have signaled something when doing a wrap up test before closing things up. Also, the fact that you could tighten up your lug nuts should have said something too. It's a bummer for sure.
 
That really sucks! But If I read correctly, you had the gears done and they were not something you did yourself. If this is correct, one would think that the shop who did the gears needs to fix this, yes?
 

wayoflife

Administrator
Staff member
That really sucks! But If I read correctly, you had the gears done and they were not something you did yourself. If this is correct, one would think that the shop who did the gears needs to fix this, yes?

Oh yeah, so that there's no confusion, this is 100% your installer's fault and they should be responsible for it.
 

dchew

Caught the Bug
Thank you all for your help (Eddie - thanks for the time and attention to this thread). I am taking the afternoon off to remove the front end and take it to the installer this afternoon. Tomorrow the new carrier gets here along with TWO new sensors - you know, just in case :)

I will pick them up and also take them to the installer. Although it is a mess, I feel much better today now that I know what the problem is, and the solution!

He will also install the RCV shafts for me and make sure everything is right. But I am thinking I will not have him put the cover on. I would like to hook everything up and cycle the locker on and off without the cover, just to be sure. Sound like a plan?

Dave
 
Top Bottom