Bad Blue WS6

iTrader: (41)

Hello all – Im putting this in both Gears/Axels, and Brakes/Susp, not sure what it is coming from. Sorry for the damn novel…here we go..

Problem – When turning sharp, I have a rubbing (sounds like a sea lion, or seal in my *** end,,, rooo, rooo, rooo, rooo,) to an almost grinding sound if going super slow,, to the point like im draggin my old 10 bolt on the road behind me….its not the brakes. Seems worse turning Right rather than left,, although, it does it when turning both ways

2000 TA M6, I have TCS and ABS - replaced the 10 bolt due to broken pinion gear

Ok, bought a used Moser 12 from a sponsor here. Eaton posi, 4:11, 31 spline, no C-clips, new bearings installed on the axels (twice),,, press rings too….all internals look great. This was my first rear end install…Got it in, had some brake issues because my dumb *** didn’t take off the 1/8th LT1 spacer rings that were on the axels (the M12 was on a LT1, so I changed the reluctor or exciter rings, brakes, etc) fixed all that. Installed the proper U-joint on my stock drive shaft…I also installed new poly ended UMI LCA’s, & Pan hard bar, and a new BMR TA,,,, all non- adjustable. (Im stock height, stock tires, etc.) All these components were lubed up in the zirts, and on the poly surfaces themselves. I tightened the sway bar clamp to axel bolts up more than what I had first tightened it to, thinking the bar was moving around to much making that “sea lion in the *** end” noise.
(I painted the axel, and noticed some marks where the clamps had “moved”) I think the torque listed in the Haynes manual was only like 18 ft-lb or something small…Doing that did remove a lot of noise, and some vibration, lol, but I still have this harsh sounding rubbing to grinding noise.. Only when turning very sharp…
NOW – I didn’t have the harsh grinding sound b4 I tightened up the sway bar clamp to axel bolts,, (I don’t think anyway, getting very confused) only a very bad “sea lion: noise,, worse than what it does now…did I tighten too much??

There is no movement in the axel if you try to move it up or down, left or right (wheel hub), feels very solid, and no noise spinning the axel freehand

I checked everything Drive shaft wise,, looks ok, I don’t have a pinion angle finder, so that was not checked, but to my eye,, (I know, I know) it looks the same as it did on the ten bolt… I did notice that when I tightened up the C clamp action on the driveshaft,, one side of the U shaped, double ended bolt is sticking through the nut like a 1/16th more than the other side of it (on both) … if that were to matter, .. Like I said,, this is my first rear-end..

Gears looked great, and I did not touch anything there, pinion, yoke, seals, inner bearings (?) etc, all were already set up… and for a used rear end, looked awesome (I think he said it was used roughly 8000 miles, he is going with FI, so he wanted a 9 inch)

TA looks good, no contact areas between the DS and the TA, although, I do notice a pinion seal leak,, not a biggie, just wet looking

I have not yet removed the cover to see inside…although, may be doing that as im running out of places to look. ….let me know if any other info is needed, I will be on here all day, and will do my best to get you any missing info…

About my only guess, is im rubbing the long bolt of the sway bar end link on the bracket it sits in when im making the sharp turns, probably due to me tightening down the clamp to axel nuts past the 18 ft-lb….but not sure,, I did torque the end link set ups to the listed amount in the Haynes manual (I cant remember what it is at the moment), and have roughly ¾ to 1 inch of that long bolt sticking out at the top,, the bushings “seem” to be where they are supposed to be.

I am lost…

Bad Diff ? how to tell?
Binding DS ? also, how to tell
Something else ? (ARRGGG!)

Plz help,, any ideas you can throw at me will be greatly appreciated.

pddye

iTrader: (14)

My 12 bolts all did the same thing with a little age on them. I just put up with it. Twice a year I'll change the gear lube out with royal purple and with new oil it will stop the groaning for a little bit. Mine also only does it when everything is warmed up.

Schantin

iTrader: (6)

If the shims are not tight enough (ie not thick enough shims) locking the carrier in place, it will exhibit those symptoms. Rebuilt the 10-bolt in my former LT1 Camaro a few years ago. Gear mesh, etc were great. Ended out hammering in thicker shims of equal thickness to either side of the carrier (important to use equal thickness shims so that the carrier position doesn't change) to tighten things up. Problem was then gone.

Good luck

Bad Blue WS6

iTrader: (41)

i wanna say the gear oil used was 75w90 (mobil 1),,,cant remember what kind of posi additive, but it was in a blue container. (like an oversized tooth paste type container)

i420tom

iTrader: (11)

If mine was doing that i would try some non synthetic GL-5 fluid and some GM BRAND additive. Should help.

Schantin

iTrader: (6)

His rear diff will probably overheat and still squeak. Aside from the 9" which requires conventional, synthetic is usually used to prevent overheating. The factory GM 10-bolt comes w/ synthetic oil for this reason. I understand this as a 12-bolt, so might be different........

As I posted earlier, check the carrier shims. If there aren't enough shims the carrier can shift slightly when making those tight corners, causing the "running over a rat" squeal. I've experienced it 1st hand......

i420tom

iTrader: (11)

I thought synthetic was not reccomended in the AUBURN but reccomended in the torsen? I have the auburn LSD and run conventional GL-5 with GM additive. DO a search on fluids i think it may be the cause of your noise as it only while turning, most people call this CHATTER. If it was on accel or decel i would say it was from pattern or pinion depth.

EPP

iTrader: (22)

The first place I would check, and double check, is at the torque arm bolts that attach the torque arm to the rear. When they are slightly loose the rear can exhibit the very same symptoms you are experiencing. Bob

9000th01ss

iTrader: (10)

True but he has an Eaton. My brothers Eaton said friction modifier isn't required but can be used.
Friction modifier in a toothpaste like tube is garbage. Those are 12oz, I had two of those in an Auburn and it made noise like described. I drained it and added 4oz ford friction modifier and never heard a noise again.

Bad Blue WS6

iTrader: (41)

got the scary grinding noise out with some sway bar re-torqueing, still have the "Peter Griffen gettin his back shaved by Meg" sound when turning sharp,,,either left or right. At this point,,,im going to re-check the TA bolts as Bob recommends, and im also goin to re-install my stocker LCA's and PH bar to see if thats what im hearing

pddye

iTrader: (14)

Bob I never thought of that but after I change my fluid I always check and retighten my bolts at that time. Guess I never put two and two together even more so when the cast rear gets hot it could make it distort and move. Learn something new every day.

Bad Blue WS6

iTrader: (41)

those were good.

Bad Blue WS6

iTrader: (41)

thought it was gone, but its still there... still have the grinding noise,,,seems to be coming from the DS up by the Tranny,,i can feel it throught the shifter.
also noticed that my crossmember (tranny) has a bad bolt hole,,when i removed the rear DR side bolt, threads came out with it...
also noticed that im getting fluid on my Y-pipe and cross member up there.

Bad Blue WS6

iTrader: (41)

i guess i just need to give it up.

Bad Blue WS6

iTrader: (41)

scratch the "turning sharp" part,,it does it when i turn to any degree....carrier bearings? is there any write ups on redo-ing these?,,,i have never removed a diff b4..

Bad Blue WS6

iTrader: (41)

practiced diff removal on my old 10 bolt,,havnt removed the 12 bolt diff yet (i dont have a 3/8th allen/socket to remove the carrier bearing caps in the M12,,,but ,,,here is my oil and pics of my pan i used when i drained the Molbil 1 75w90 with auto zone-ish 12oz posi additive AFTER 40 SOME MILES (and thats being genourous,,more like 20 some miles of under 30mph driving)..is this normal? i have what looks like metalic black paint ! no big chunks of anything, and the pinion and ring look great,,,but still have mucho big grinding (like im dragging a concrete block,, solid grinding, but ONLY when i turn to any degree..going straight is noise free,,,) pics arnt the best, but you'll get what im saying,,,,every "dot or spec" you see in the black tray is metal.








as i mentioned,,this is my first rear end anything,,,and dont know if these "dust like metalic particals" are normal,,which im thinking they are not.

will be checking the shims and maybe pulling the eaton out and inspecting the inner carrier bearings (timken set 36) tomorrow once i get the 3/8 hex head

Bad Blue WS6

iTrader: (41)

up top for any info..

Bad Blue WS6

iTrader: (41)

it was my shifter (installed the same time as rear end),,,two bolt holes in the tranny where completely gone),,, tapped em, and shes good as new!

Black 99 Bird

iTrader: (31)

Wow, did not see that coming.