Think its bearing(s) in the diff.

whine in rear end... seems centered.. (thought initially it was a wheel bearing, but now think it is in the differential..

'99 F-150 4x2 4.2L

axle tag says: 3-S-829A then 3 L 55 8 8 8 M 01

Read horror stories about swapping out gears on one's own, but am wondering about bearing and seal replacement on my own..

Also rough estimates on parts?

Where to buy from?

Got a Chilton's online CD manual, but the procedure seems TOO simple they way they've got it written.

Any advice would be appreciated.

thx

JT

 

developed whin after extended warrenty ran out,72000,progressivly got worse finnally took it in after u-joint replacment and fluid change...pinion bearing and carrier bearings bad...600 clams,but that was from a shop i know so it will be more,unless you know someone

 

A friend of mine has a 99.....same problem. Had to get a new rear end.The 3L55 translates 3:55 gears.The "L" means limited slip.8 8 means its an 8.8" rear end.Dont take it to Ford.Go to a just axle and gear shop!!Take my word on that!!

 

Hi Jhthornley
I just got mine out of the shop just last week 95 f-150 2x4 4.9 it has 8.8 with 3:55 no L/S
I would first check the carrier bearing (center bearing)for the driveshaft if you have a supercab. They make a lot of noise when they go bad and often sound like rearend noise.
I had to have a bearing kit installed in mine at a trans shop in my area $150 parts $250 labor.
To check your center bearing disconect your driveshaft at the rear and remove rear shaft put it gear and give it a spin to see if the noise still exists.
For $400 dollars I think it was better to allow them to handle the smelly repair not to mention i don't know anything about rearends.

 

thx guys...

I'll check out the carrier bearing bit..

other than that, I'm kinda at a loss...

one concellation, my brother (about 5 hrs drive) is a master mechanic... I might take the thing up to him??? not sure though... his wife is a B!TCH...haaa

thx again for the input..

JT

 

Maybe I should clarify the problem with mine. I had the bearing kit put in the differential it was not the center bearing for the driveshaft. It was a bad pinion bearing like I suspected,was making a loud whirling noise when it got over 15mph I only had 82000 mi.on the truck.
Driving 5 hrs. is NOT a good idea. I would find out the problem as soon as possible if something breaks in the rearend it will cost you a lot more money. Gear parts are expensive. Just my 0.2

 

Sin,

you mention a "bearing kit" for the diff..

do you have a part number, or list of part numbers... OR a list of the parts included in the kit?

I understand the center bearing bit now. Yep, I was confused.. assuming that you replaced that.. I realize now that you had bearings replaced in the diff..

Am wondering about doing the bearings myself, but my chilton's manual (online CD) has the following steps for removal & installation of "Axle shaft, bearing and seal" (can't find any other sections that are appropriate).. (manual is kinda weak IMO)..

1) raise and support rear on jackstands
2) remove wheels from drums (mine's got discs)
3) drain diff fluid by loosening cover bolts
4) remove brake drums
5) remove diff cover and gasket (some don't have gasket)
6) remove side gear pinion shaft lockbolt and side gear pinion shaft (its got pictures of this step, and I understand it)
7) push the axle shafts inward (one at a time), and remove the C clip that holds each in the diff (C clip lives in a groove on the shaft). (picture of this too.. understood)
8) temporarily replace the side gear pinion shaft and lockbolt to hold gears in place
9) remove the axle shafts w/ slide hammer... be careful not to damage seals w/ splines on the ends of the axle shafts... (why we're removing the axles, I don't know??... is the slide hammer necessary, or will they just slide out??)
10) REMOVE THE BEARING AND OIL SEAL FROM THE HOUSING.. both the seal and bearing can be removed w/ a slide hammer.. (no pictures of this... Q: one obvious bearing, or are there a few in the diff? Q: Slide hammer to remove...??? seems a bit much)

it then goes on to talk about press fit and loose fit bearings, and that either type may have been installed at factory... (don't sweat a "loose" bearing as being bad necessarily).

at this point the removal is basically complete... inspect this, inspect that... wipe down... check seals... replace if necess etc..

I'm basically confused as to what bearings to buy... (my guess is the pinion bearing, as in Sin's case, but not sure what other bearings and seals I might find when I crack it open)

Will check it out this wkend...

any thoughts??

thx

JT

 

JT
I looked up the receipt and it has no part listed,"sorry" from what I understood they had a kit to replace all the bearings in the rear.

He did mention if he tore it down and found a bad axle bearing it would be a bit more money but everything must have checked out.

My Chiltons book lists all the part # in the diagram the one on line should be the same. My truck is a 95 I'm not sure if there the same.

If the rears are the same and not online make a list I'll send you the part #"s

Maybe someone a little knowlegable will have more input before this weekend.
Keep posting on how it goes good luck !

 

well,

I bought a pair of side bearings, but couldn't get my rotors off myself, so I took it to a local guy.

found that a "bearing kit" does NOT include the "side bearings"... why? I'm not sure??? Any of you guys LMK if I paid twice for those bearings.

Anyway, dude replaced 6 bearings (2 axle, 2 side or differential bearings, and 2 pinion bearings)... seals as well.

Parts: $220 (excluding gear oil)
Labor: $370 (not sure why so much???)

I did supply my own Redline 75W90 limited slip gear oil (I know... I know... it is supposed to be 75W140... but I've read so much on here that I think the Redline should be good).

Now for the deal... Mechanic said that there is still some noise at 40-45 when letting off gas... THIS IS TRUE..., but I can notice some general noise at speeds as low as 20.. noise is MUCH better, but for $600, I was expecting MINT...

Q: Is the 90 weight oil too thin?... I doubt thicker oil would "hide" the noise.

Q: Should the pinion nut and/or whatever be tighter/looser than it currently is??? Dude said he's got it set "right"... backlash this, shims that... etc...

Opinions guys???... other than the obvious... I got SCR*Wed??

thx

JT

 

I am going through the same type of deal with my 99's 9.75 rear.

We took it apart, replaced axel bearings, and the first (small) pinion bearing, the other looked good, so did the carrier bearings.

Put it back together, and used synthetic 75w90 lube.

Damn thing still whines at any faster than 40km per hour(30mph), and now my rear is klunking on bumps and corners.......sign of bad spider gears???

Any way.....I hate the 9.75!!!!!

 

my diff is leaking now, so I'm gonna carry it back to them Monday AM.

Not overly impressed by the guy who was recommended to me at this point.

 

This maybe stating the obvious, but our truck have an inherent drivetrain whine...my father has an original 97, and I have a 01...both whine around 15 mph. It is audible in the cab.

If it's making groaning noises, that might be a different story!

 

jhthornly,

I think the slide hammer was for the rear wheel axle bearings mentioned in the Chilton's. One of mine is leaking now, after doing a diff carrier change, and I am looking at changing it.

Need to pop out the old one and put the new one in, but I hope I don't have to press it in, since that would be tricky in the backyard garage.

 

Just a question, you didn't recently have the fluid changed in the rear-end have you? Only asking because if that is the case maybe they didn't add the friction modifier...

 

Has anyone replaced the rear axle bearings and had to press fit the bearings?

How was this done?

Is the loose fit bearings a lot easier?

How does one know which is installed prior to removing the old seal and bearings?

Inquiring minds want to know.

Thanks.