I'm a bad person. I changed my diff fluid at 76K miles for the first time.

About 2-3 years before that, though, I started hearing some sounds in the rear end. At low speeds, there's just some extra noise that I know isn't tire/road noise, but like a constant dull metallic sound. When I'm coming to a stop I'll hear thump thumps and they'll get fewer and further between as I come to a complete stop. So my friend and I thought it was the diff, but I was lazy....until I changed the diff fluid about 9 months ago. The sound didn't go away at all. My friend said it might be wheel bearings. I'm a noob to all this, so does that sound like a possibility? Are there any other more likely candidates?

I want to say that I did everything right with a diff fluid change, didn't think it was really that hard. Used 2 qts Royal Purple, new gasket, wiped off the collected shavings, no leaks on the floor or visible wetspots on the diff itself. But I noticed that afterwards, if I'm exiting the highway on one of those 270 degree offramps, I'll hear a whirring noise from my backend. As I straighten out the car, the whirring noise goes away. Any ideas?

 

i have a 95 formula and im having the same prob..i used the same ryal purpal and all

 

Im in the middle of changing my wheel bearings this friday for the third time, this is the story.

thump thump thump sound.. yea wheel bearings.. cool changed them out.. 3 months later thump thump thump comes back.. so I ask on here guys say that it is most deffinatly my axles are bad.. ok I ignored him becuase I found a leak on my passenger side so Im like wheel bearing went bad due to seal leak..

so I change the bearings again but when I pull the axles this time I look at where the axles ride on the bearings.. Sure enough the passenger side was fine looked like smooth metal.. but on my side.. it looked like someone was taking a grinding wheel to the axle kinda looks like a lie detecter test but in some area's good but then way bad then somewhat bad and smooth bad. cant really describe it but you will know if your metal is shinny like its supposed to look..

anyways.. possible you will need

1. axles summit racing has the cheapest you will find anywhere your rear is 7.5 the Moser sells em they make two the more expensive one is for a car with traction control..

http://store.summitracing.com/partde...642+4294908216

http://store.summitracing.com/partde...42+4294908216+


Look at those to make sure those are what you need just double check behind me and make sure I dont want to get cussed out..

2. 2 quarts gear oil 75w90 but you know that already
3. posi additive for your gears.
4. bearings
5. bearing seals
6. diff gasket
7. Optional I use the black rtv gasketmaker sealant what ever you prefer I make sure bitch dont leak..

so for the axles if you need then and the materials your looking at 320 with axles arond 63 65 without axles ...

on top of that the tools you will need are..

1. slide hammer
2. WHEEL BEARING PULLERS never go to a woman at autozone she gave me jaw puller
3. Caliper tool for when you get ready to put it all back together..

for tool rental your look at a additional 150+ depending on where your renting from.. but you get this back of course..

Procedure..

loosen lugs jack car
pull diff cover let drain.
take off rotors calipers cool
find 8mm bolt that holds this block inbetween your axles..
take 8mm bolt out pull block out..
then push axles in "C Clip will then fall out be READY both times i did i got lucky they just lean and i could pull them out with my faingers..
pull axles
remove seals you can use a prybar or a big screwdriver I just used the end of the axle you'll see
then use your fancy bearing puller and attach to the bearing then
attach slide hammer to bearing puller RIP that bitch out of their
repeat other side..
look at axles and all surfaces to see if their is any damage..
in housing and on axles..
if all good
bearings need some grease pack em with your choice bearing grease..
use slidehammer/bearing attachment in reverse order..
for the seals
I insert the seals take the bearing attachment off and stick the shaft of the slide hammer into the housing and then slightly tap the seal it you want a nice even surface with no dents in your seals take your time with this.. I saw where i messed up with my previous install..
ok now thats done
reinsert axles, C Clips block tighten 8 mm bolt
clean diff cover/housing I use the black sealent on the houseing then on the cover attach the gasket to the cover then cover to housing..
next is add additve first, then your two quarts of gear oil..
attach rotors..
caliper tool for the calipers of course
tires tighten lugs..
lug covers for me stock rims if not your good..

I usually let it sit for my sealent to dry.. but its your choice

Ive done this twice so thats what your look at man..

Ill be doing this again this friday this time no noise "should be my result"

hope you dont need axles man and I hope this helped you out...





and also i noticed that your in external engine asking about wheel bearings sorry im not trying to be a *** but I found most my help in the gears and axles section..

 

Go to the GM dealer and put a $7 bottle of additive (friction modifier) in it and that should help on the offramps.

 

Wow! You guys are awesome! Thanks for the info! Guess I need to scrounge some dough now...

And sorry about the posting in the wrong forum...I actually found ls1tech through a link, and the link was straight into the "Ls1-ls2...performance" section...didn't even know there was more to this site!

Thanks again!

 

I would most deffinatlly try sombitches method first though to make sure if noise persists then go with my method.. just be prepared.. I wasnt

 

i have a sound kinda like this but on the front driver side i think, i did my brakes new pads and rotors turned didnt go away and i have just ignored it. could it be wheels bearings?

 

Here I go resurrecting an old *** thread but...I only recently changed wheel bearings.

Quick little tip:
The one thing missing from every writeup, Haynes manual, and GM Service Manual was that in order to push the axles in far enough to get the C-clip off, you need to remove the ABS sensor from behind the hub. (That took us like 1.5 hours to figure out)

We took the axles out and did a quick inspection but didn't look like it was a problem. Wheel bearings themselves looked ok too, but since we were this far, we replaced 'em. Sound is still there.

I've heard Carrier Bearing and Pinion Bearing, but are those referring to the same bearing on the driveshaft?

 

bump...

 

dont forget u have carrier bearings and pinion bearings also.
it will make the same sound as wheel bearing but centered in the rear instead

 

Are these on the drive shaft or in the diff?