Noise I can’t pin down

[ghetdjc320]

Been dealing with a weird noise for a few months now. It first started on a 500 mile drive from Arkansas to Texas. It is frequent but doesn’t have a definite rhythm. It sounds like a bearing going bad. Kind of a lite metal grinding noise almost like a bad u joint. It starts around 20 mph and comes and goes at random intervals. Here Are some more details:

new front and rear gears (revolution 4.56) with bearings

rear has a truetrac and revolution chronology shafts

just replaces the rear axle bearings and seals

replaced front unit bearings

rebuilt transfer case

engine has about 8000 miles since full build

new axle shaft u joints

 

Tried transfer case in neutral and ran transmission through all gears (aw4). Tried jacking up rear and running it while listening for noises. Transmission oil is very clean and at the proper level. I am at a loss as to what this noise is. I’m grasping at straws but please let me know if you have any ideas. Also, keep in mind that I’m in Guam so specialized tools are not readily available. 
 

thanks in advance!

[ghetdjc320]

Also have new front and rear driveshafts and u joints to eliminate that as a cause

[Andy in Pa]

Do you notice more when turning?  Due to the range of new parts you have done recently, you have eliminated 80% of the possibilities.  Do the front brakes have the spring clips in place holding the pads properly?  This can cause a light scraping and clunking or clicking sound if they are not clipped in place properly.  Sounds very much like something more serious too. 

[eaglescout526]

The rear ebrake cables can make a scraping sound and rub on the back side of the rim.

[ghetdjc320]

6 hours ago, Andy in Pa said:

Do you notice more when turning?  Due to the range of new parts you have done recently, you have eliminated 80% of the possibilities.  Do the front brakes have the spring clips in place holding the pads properly?  This can cause a light scraping and clunking or clicking sound if they are not clipped in place properly.  Sounds very much like something more serious too. 

No difference when turning. The brakes just have the clips for the piston but otherwise they are just floating on the “wings”. It does sound a bit like something rubbing the rotors outer edge but I don’t believe it’s coming from the brakes at all

[ghetdjc320]

6 hours ago, eaglescout526 said:

The rear ebrake cables can make a scraping sound and rub on the back side of the rim.

checked that too and there isn’t any interference. 

[Warren Mohler]

I have seen later style 231 rear output seals make noise

[ghetdjc320]

1 hour ago, Warren Mohler said:

I have seen later style 231 rear output seals make noise

rebuilt np231 with new output housing/seal and bushing

[ghetdjc320]

I’m thinking front diff possibly. Will investigate further. 

[Andy in Pa]

5 hours ago, ghetdjc320 said:

No difference when turning. The brakes just have the clips for the piston but otherwise they are just floating on the “wings”. It does sound a bit like something rubbing the rotors outer edge but I don’t believe it’s coming from the brakes at all

 

There are these spring clips that go over the "wings" on the brake pad mounts that provide a bit of resistance to the pads so they are not able to float as much.  What happens is the actual "wings" that the brake pads ride on get grooves worn into them over time by the metal bracket on the pads, which allows the pads to float more than they should.

 

There is no way to truly fix this besides putting on new outer knuckles, but those spring clips help control the pad float.  

[ghetdjc320]

2 minutes ago, Andy in Pa said:

 

There are these spring clips that go over the "wings" on the brake pad mounts that provide a bit of resistance to the pads so they are not able to float as much.  What happens is the actual "wings" that the brake pads ride on get grooves worn into them over time by the metal bracket on the pads, which allows the pads to float more than they should.

 

There is no way to truly fix this besides putting on new outer knuckles, but those spring clips help control the pad float.  

 

interesting, I’m running black magic pads but they didn’t come with the clips you are referring to. Even with the floating though, I can’t see how they could cause the grinding noise I’m hearing. Also, the noise doesn’t change while braking. I was planning a swap to the pre 90 knuckles for brake upgrades after I fix this stupid noise though. 

[ghetdjc320]

I was try to think of what this noise sounds like to give more perspective. The closest think I can think of is a drill press at like 300 rpm drilling lightly into heavy steel. Definitely a metal on metal sound. I wish I could record it clearly

[Andy in Pa]

2 minutes ago, ghetdjc320 said:

 

interesting, I’m running black magic pads but they didn’t come with the clips you are referring to. Even with the floating though, I can’t see how they could cause the grinding noise I’m hearing. Also, the noise doesn’t change while braking. I was planning a swap to the pre 90 knuckles for brake upgrades after I fix this stupid noise though. 

Ok, yes it should definitely go away when braking.

[ghetdjc320]

Here is a short video clip on the drive home. The phone was able to pick up the noise especially around the last 3-4 seconds of the video. 

[schardein]

I had a light roaring noise in my high mileage XJ that would come and go.  Turned out the old rubber transmission mount was oil soaked and super mushy.  New trans mount solved it.

[ghetdjc320]

My trans mount is new too

[ghetdjc320]

Turns out the noise is my carrier bearing. They are new but it must have been damaged when installed or defective. Will get all the diff bearings swapped out 

[ghetdjc320]

Just incase anyone sees this in the future, I rebuilt my ring and pionion and installed new bearings and set the proper preload, backlash etc. Everything turned out great, but the noise was still there... Turns out it was actually the front transfer case output shaft rear needle bearing. The noise was very hard to pinpoint and it’s that ridiculously hard to get out bearing. Part number J2416 from Timken. 

[BeatCJ]

Thanks for the follow up.