smbstyle

iTrader: (1)

I was under the car tonight just giving it a once-over before my next DE this weekend at Daytona, and when I glanced back at the diff I noticed a green ring of buildup right in front of the diff, surrounding the driveshaft flex disc. When looking at it closely, the front of the diff is completely dry, as is the flex disc, and I could not find anywhere on the driveshaft, flex disc or diff that was wet, yet this green "goup" was built-up in a ring. It isnt oil, it is much thicker, like a heavy grease.

Car has the OEM diff with 1 track day and about 10 auto-x events, no whining, just inspected it about 2 months ago and changed the diff fluid then with AMSOIL Severe Gear Oil 75w90. Diff doesnt whine, havent had any issues with it at all. Re-checked the area around the diff about a month later after the diff fluid change and a lot of spirited driving and that buildup wasn't there....

Here are a few pics:










Anyone else ever seen this before or have any idea where to start?

chitown21y

iTrader: (6)

Pinion seal maybe...

DMM

Yup...pinion seal. What GEN diff do you have? I have heard the early ones did not seal up easily.

smbstyle

iTrader: (1)

thats what i thought originally, but now im not so sure.... it seems like the driveshaft coupler may be shot and slinging grease out of a crack, or there is a tear in the cv joint on the driveshaft which is slinging grease. The pinion seal typically leaks down the front of the differential and you can see a trail of fluid dripping down.

here is a description of the driveshaft coupler shot, and the cv joint on the driveshaft being torn:

see post #17 through #19.
http://www.cadillacforums.com/forums...ne-have-2.html

see post #41.
http://www.cadillacforums.com/forums...ml#post2126797


here is what the pinion seal leak looks like, clearly diff fluid leaking, which doesnt seem to be my case:

Driveshaft Shop

The grease inside the CV is Green in color, its either the seal on the two mating surfaces or the boot. have you had the shaft off recently ? if so the ends are machined flat but if there is even a little grease on either surface there will not be a good seal. take the bolts off, clean it real good and use a little RTV on the surfaces.

smbstyle

iTrader: (1)

no, driveshaft hasnt been off the car since I've owned it.

so is this a repairable issue? from what I have been reading these CTS-V driveshafts arent serviceable and if there is an issue with them you have to buy a whole new driveshaft... any truth to that?

Thanks for the reply!!

Driveshaft Shop

If a part breaks you would need to replace the shaft,i believe you have something there you can fix. take a good look around the boot area and where the CV mounts to the rear flange of the Diff. might want to even check the torque on the bolts, if there a little loose this will let grease out.

z28C4maro82z

iTrader: (33)

I had the same problem on mine, my driveshaft soon went. I'd be careful. I bought a new driveshaft. The part of the driveshaft that meets the pinion on the diff was loose as hell. I could wiggle it almost effortlessly. Time for a new shaft because you cannot service these shafts

smbstyle

iTrader: (1)

DING DING DING!!!

Took it to the shop today, my mechanic looked at it and the bolts were very loose, causing the grease to sling out. He repacked grease in there, the bearings were in great shape, tightened everything down really good and put loc-tite on the bolts. Everything looks good so far, he's pretty sure that fixed it, so I will put some miles on it today and re-check.