Rear end is howling

02 LS V8 3.9 140k miles.

Hello all,

New noise. The rear end is howling. Gets noticeable at about 40mph and changes pitch, not volume, as speeds increases. I cant tell if its louder on the left or the right. My tires (GoodYear Eagle GT's) are about 80% worn and still above the wear marks. I usually keep them at 32. I was thinking it might be wheel noise so I took them down to 30 psi just to see if the noise changed any. No change. I've been looking around thinking it may be bearings but I don't see any information on rear bearings on this car. Any advice on troubleshooting this would be greatly appreciated.

Thanks in advance

Does the sound change as you go around turns? I realize you probably are not taking turns very sharply at speeds above 40mph, but if you can find a place where it's safe to so do, you might try that and see if the noise changes.

Also, does the noise change if you let off the throttle? If so, it might be the pinion bearing or just the gear mesh. You could try changing the differential oil to see if that helps.

-Rod

Does the sound change as you go around turns? I realize you probably are not taking turns very sharply at speeds above 40mph, but if you can find a place where it's safe to so do, you might try that and see if the noise changes.

Also, does the noise change if you let off the throttle? If so, it might be the pinion bearing or just the gear mesh. You could try changing the differential oil to see if that helps.

-Rod

to the throttle question no. I ran it up about 60 and slipped it into neutral and let it roll and the noise was still there until it got below about 40. To the high speed turning test, how sharp a turn do you suggest? enough to shift the balance or tighter?

If the turn is enough to shift the balance of the car, that should be sufficient. Basically, it should be sharp enough to load one wheel bearing while unloading another. If the noise changes during the cornering, you're probably looking at a wheel bearing issue.

-Rod

If the turn is enough to shift the balance of the car, that should be sufficient. Basically, it should be sharp enough to load one wheel bearing while unloading another. If the noise changes during the cornering, you're probably looking at a wheel bearing issue.

-Rod

are there rear bearings? i know that sounds ridiculous but I looked at a parts breakdown for the rear and there doesn't seem to be a bearing or bearing hub listed. I know it still has the OEM parts on the rear and if there are bearings, its most likely time to replace them anyway. Still have yet to do the road test, is there any other way to test for loose or worn bearings? ...like the old school way of lifting the car and shake testing the wheel for looseness or play?

are there rear bearings? i know that sounds ridiculous but I looked at a parts breakdown for the rear and there doesn't seem to be a bearing or bearing hub listed. I know it still has the OEM parts on the rear and if there are bearings, its most likely time to replace them anyway. Still have yet to do the road test, is there any other way to test for loose or worn bearings? ...like the old school way of lifting the car and shake testing the wheel for looseness or play?

Ok, i'm feeling a little stupid asking the bearing question, i was looking at the wrong diagrams. So I will go ahead and replace both rear bearings this weekend. Any advice, do's and don't s before I start this would be greatly appreciated. Rod, or anyone else, I always like to review the shop manual before I do any work on this car so if you have one please do share.

Thanks in advance.

Have you located rear bearings for sale yet? I took a look at Fast Parts Network. The OEM is part of the knuckle at about $800 each side.

-Rod

Have you located rear bearings for sale yet? I took a look at Fast Parts Network. The OEM is part of the knuckle at about $800 each side.

-Rod

I saw that too but i'm confused. The local parts stores sell just the bearing for about $45 each side. The FPN site sells the whole kit for about $800. Do I need the whole kit or can I get away with replacing the bearings only?

I saw that too but i'm confused. The local parts stores sell just the bearing for about $45 each side. The FPN site sells the whole kit for about $800. Do I need the whole kit or can I get away with replacing the bearings only?

if for 45 a side i would pull axles and take them to a shop to get them pressed on. if you do this check for play in axles before removing them.

good luck...

if for 45 a side i would pull axles and take them to a shop to get them pressed on. if you do this check for play in axles before removing them.

good luck...

Yikes, don't think i am comfortable pulling the axles out. According to the procedure you sent the bearings do not have to be pressed on. Is there something I am missing here? Is pressing on the new bearings a requirement or it that optional?

Yikes, don't think i am comfortable pulling the axles out. According to the procedure you sent the bearings do not have to be pressed on. Is there something I am missing here? Is pressing on the new bearings a requirement or it that optional?

i could be wrong call where you called and ask them if those are still pressed on. on these newer ones but every ford rear end on a ford i've worked with rear wheel drive had to be pressed on. it's not hard as you think if i'm right you have to take wheel and drum off and there 4 nuts inside the axle holse and you get them nuts off and it pulls rite out.

i could be wrong call where you called and ask them if those are still pressed on. on these newer ones but every ford rear end on a ford i've worked with rear wheel drive had to be pressed on. it's not hard as you think if i'm right you have to take wheel and drum off and there 4 nuts inside the axle holse and you get them nuts off and it pulls rite out.

well according to manual, everything comes apart and goes back together by just dissembling and reassembling with hand tools. It says the axle shaft retaining nut is a one time use and cannot be reused. It also says to get a new, lower arm-to-wheel knuckle bolt nut, and the upper ball joint-to-wheel knuckle nut. Then it says to reinstall in reverse order. Nothing about having the bearings pressed on.

I was asking because Rod mentioned pulling the axles and having the new bearings pressed on before reassembling the knuckle. so i guess i need to know if reassembling with hand tools is ok.

I just want to be absolutely sure of what needs to be done, special tools and or processes, etc. before i start this. I hate surprises.

Thank you for the reply.

I didn't mention pulling the axles and pressing in new bearings.

But, if you can buy the bearings, you may be able to press them off the hub and new ones back in. I'm not sure about that though. If you have alternate transportation you could certainly disassemble it and take it to a machine shop to find out if they can be separated.

The process Scrapper mentions is mostly how a solid axle Ford works (also need to pull the differential cover and remove the c-clips), but the LS uses an independent rear suspension set up with half shafts, knuckles, and hubs. I suspect the hubs are pressed in to the sealed bearings, but that the hubs can be removed from the knuckles by loosening bolts and sliding them out. Since your car is in Texas, it may not be corroded in place like the front bearings were in my wife's LS.

-Rod

I didn't mention pulling the axles and pressing in new bearings.

But, if you can buy the bearings, you may be able to press them off the hub and new ones back in. I'm not sure about that though. If you have alternate transportation you could certainly disassemble it and take it to a machine shop to find out if they can be separated.

The process Scrapper mentions is mostly how a solid axle Ford works (also need to pull the differential cover and remove the c-clips), but the LS uses an independent rear suspension set up with half shafts, knuckles, and hubs. I suspect the hubs are pressed in to the sealed bearings, but that the hubs can be removed from the knuckles by loosening bolts and sliding them out. Since your car is in Texas, it may not be corroded in place like the front bearings were in my wife's LS.

-Rod

My Bad, that was someone else s comment.

I got the job done with a few tips.
Breaker bar
36 mm 3/8 drive socket for the shaft bolt
decent puller

the bearings had to pr pressed out and back in.

The knuckle wasn't rusted out but it was a battle to get them to separate. The left was worse because that was the bad one. When pressed out you could smell that the metal had been very hot. So if the howling starts, get it done quickly.