Need assistance with front end rebuild (1 Viewer)

[neal0124]

I just finished the rebuild of my front end on my 95 fzj80. I replaced all the bearings/races, seals, rotors and also the brass spindle bushings. I did not replace the brake pads because they were replaced about 3 weeks ago with 100 series pads and have plenty of meat on them. One of the caliper mounting bolts was missing its washer. I re-installed that bolt on the top of the caliper just in case it backed out the caliper would have less a chance to bind up with the wheel and lock it up. Going to replace the bolt/washer asap.

I just took the cruiser on a quick 8 mile test drive around the block and then onto the freeway. On the freeway, while coming back, I was going about 65mph. All of a sudden the truck started making a horrible, extremely loud whirring/squealing noise. I pulled onto the shoulder and parked. Got out to check for any signs of the noise and saw nothing out of the ordinary. Started her back up and got moving again, the noise didn't continue. I got off the freeway and decided to get fuel. As I was driving down the road towards the gas station the noise came back. I was traveling about 35mph this time. I slammed on the brakes until the noise stopped, at around 5-10mph and then accelerated, the noise stopped. I've checked the brake dust shields for contact on the rotor and they arent touching, I've also jacked the front end back up and checked for loose wheel bearings and there is no wheel movement.

This is my only mode of transportation and I need to get to work in the morning. I need to get this resolved as soon as possible so that no major damage to the axle is done.

Thanks for any assistance you can give me.

 

[Kernal]

Did the vehicle pull to either side either with or without braking? Calipers still snug? Did you pack the birfields with grease before you installed them? Add grease to the steering knuckles and the new spindle bushings? Could it be slipping belts??

 

[neal0124]

Belts are not slipping, definitely no a belt slipping kinda noise.
Birfields and knuckles were stuffed with new moly grease. I think I used 4.5 tubes total.
The new spindle bushings got plenty of grease.
The truck did not pull to either side, tracks perfectly straight on/off throttle and under braking.
The calipers are still tight, although the pads need to work themselves into the disk face since they had slight grooves in them from the old rotors. All the machining oil was cleaned off the rotors before they were installed also.

I used a combo of the FSM and the rebuild thread in the FAQ section. Followed those directions to the T.
I'm at a loss here. Other than the noise the truck feels great. This noise is loud and alarming, something is definitely not right.

 

[Kernal]

Could it be a stripped drive flange? Brake pad depth indicators dragging on a rotor somehow?? The only thing that wasn't quite right was the brake caliper bolt, correct?? Can you record a video/sound clip and post it to you_tube? Wait for the experts to chime in.

 

[neal0124]

The drive flanges look perfect.
The pad indicators are nowhere near the disk.
Yes, the only thing wrong was the missing caliper bolt washer.
The only way to record the noise is with my phone, and it seems to do it randomly. I don't know how to get it to make the sound other than drive it around and wait for it to go off again. I also can't determine what side it's coming from. It sounds like a grinding, metal on metal rubbing noise, but stops as soon as I slow to a certain point.

 

[Stylo07]

Do you see signs of anything dragging/scraping the inside of the wheels or rotors? Are either of the hubs unusually hot after driving?

 

[fj4068]

Gear oil refilled in differential?

 

[neal0124]

Do you see signs of anything dragging/scraping the inside of the wheels or rotors? Are either of the hubs unusually hot after driving?

No signs of scraping or dragging. The passenger side hub does seem to be hotter than the drivers side, but no too extreme.

Gear oil refilled in differential?

Yes, probably a little overfilled, I need to drain some out tomorrow. I filled it while still on jack stands and my driveway is slightly inclined. Put a little over 3 quarts in it.

 

[neal0124]

So I drove it to work and back, 55 miles round trip. It didn't make the noise again. After I drove it around yesterday the passenger side hub was hotter than the drivers side, I only drove it about 8 miles to get them up to that temp. Today as soon as I got home from work I checked the hubs and neither of them were hot.

I'm still getting this whirring/rattling sound from my front end though. That's what prompted me to do the front end re-build. The whirring is not as loud as it was. Kinda like driving over the rain grooves on the freeway, and it isn't constant. I thought it was from the spindle bushings being dry, but I changed those out and the old ones were completely covered in grease still. It seems to happen when under light throttle or as soon as I let off the throttle and start coasting. It only developed 2 weeks ago after putting my 2" ironman lift on. What's the consensus on this noise? A bad diff? Or can a birfield start making a sound similar to this before it goes completely bad?

Once again thanks for the help.

 

[Kernal]

It seems to happen when under light throttle or as soon as I let off the throttle and start coasting. It only developed 2 weeks ago after putting my 2" ironman lift on.

U-joints??

 

[FloridaCruiser813]

have you greased your front u joint?

 

[neal0124]

U-joints??

have you greased your front u joint?

I greased the originals to see if that made a difference, when it didn't I put new ones in. I know the noise is from the front because I've pulled the drive shaft and its quiet.

 

[ajax1]

loose pinion nut?

 

[neal0124]

loose pinion nut?

Is there another way to check for this besides dropping the front drive shaft and checking the nut? Grab the flange and check for play? Try to wiggle it up down, side to side?

 

[CruiseOrlando]

I greased the originals to see if that made a difference, when it didn't I put new ones in. I know the noise is from the front because I've pulled the drive shaft and its quiet.

It's not about it being quiet. You want fluid movement on the yoke, no stiffness when rotating the u-joint around.

When you take the shaft out, rotate the ends around slowly. There should be no stuttering movements, no stiffness - just pure fluid movement from any one direction to another.

If you don't have that, you need to replace the joints. Your issue may well be a bad ujoint(s).

 

[BiggSean]

It's not about it being quiet. You want fluid movement on the yoke, no stiffness when rotating the u-joint around.

When you take the shaft out, rotate the ends around slowly. There should be no stuttering movements, no stiffness - just pure fluid movement from any one direction to another.

If you don't have that, you need to replace the joints. Your issue may well be a bad ujoint(s).

He replaced the u-joints with new ones already. The sound was there before, and after the replacement.

 

[CruiseOrlando]

He replaced the u-joints with new ones already. The sound was there before, and after the replacement.

Somehow I missed that comment.

It could be due to the new driveshaft angle after the lift. If you still have your original springs, you might consider swapping back out and see if the noise goes away.

 

[Crashdix]

Have the same issue after my 3" lift - mics on transfer and tranny showed no source. Ruled that out for now. Have to replace pinion seal so will take a peek in there while I am at it. New diff oil - old was old but clean - no metal. Need to check spindle bushings as well - u joints seem fine but may give that a shot as well - its funny how many threads on this and soooo many open ended questions. It seems like such a common occurrence with no definitive answers - bummer - although I love my cruiser I hate spending a fortune "chasing" a problem like this. If I have any luck along the way I will post it.
For background: had most of front end rebuilt - birfs pulled and repacked, all new seals, etc. no noise for about a year then put lift on and shortly after this grinding type noise on and off a floating pedal at speed (over 40 mph or so). New angle makes all the sense in the world but still cannot find culprit. "drive it till it breaks" is all my wheeling friends can come up with but a jeep is cheaper to fix! Also, would hate to have a missed $300 repair cause a $2000 rebuild - just my luck!!! beers

 

[Kernal]

Spun or spinning spindle bushings?? Water pump bearings?? Idler pulley or AC tensioner pulley bearings?

 

[ajax1]

u pulled the front shaft too right did sound go away or still there?