: Rear Diff???



gregj1006
05-27-13, 11:03 PM
Have an 05 cts-v. Have the clunk and have ordered all revshift has for us. Wondering if I should replace rear diff while the revshift stuff is going in and if so will this one work for my car? Will the PCM programming be necessary?

http://www.ebay.com/itm/2008-CADILLAC-SRX-REAR-DIFFERENTIAL-CARRIER-3-91-G80-LIMITED-SLIP-CTS-V-UPGRADE-/171002214911?pt=Motors_Car_Truck_Parts_Accessories&hash=item27d086b9ff&vxp=mtr

Appreciate any/all replies

darkman
05-27-13, 11:41 PM
I don't know if it will fit or not. I would check the part number with a GM parts person. Assuming it will fit, I think the only reprograming would be for the speedometer/odometer. I also suspect, but do not know for sure, that any shop with a GM Tech II Scanner can reset the final drive ratio. Finally, it may be inherently nosier assuming the 3.91 ratio is achieved using 43-tooth ring with an 11-tooth pinion gear. (Our 3.73 has 41-tooth ring with an 11-tooth pinion.)

QwkRhino
05-28-13, 12:05 PM
Yes it would fit, but you would have to change the pinion flange to part #19179934 and cut off about a inch off the tip of the pinion in front of the diff. Easy to do. I just went this route keeping the 3.73 Ratio and getting a brand new diff from a SRX that would be as strong as a 3rd gen diff in the V and you would have to do the same mods I mentioned above. This seller took my offer for $480 for a brand new one. Check it out. http://www.ebay.com/itm/251221874036?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649. PART # 19178781
Make sure you get the G80 option for limited slip and Gt4 option for 3.73. Good luck.

ls6junkie
05-29-13, 11:01 PM
QwkRhino, That is some great information. Do you have a picture or better way to explain the inch of material we have to cut off? Also what is the process for changing the pinon flange, I assume it is all accessible outside of the diff, I.E. we don't have to split the case, correct?

darkman
05-29-13, 11:40 PM
http://www.cadillacforums.com/forums/cadillac-cts-first-generation-forum-2003/93535-cts-v-differential-swap-cts.html#post1315416

http://www.cadillacforums.com/forums/2004-2007-cadillac-cts-v-general/114547-update-rear-end-ratio-change-3-a.html#post1176233

ls6junkie
06-02-13, 08:51 PM
Interesting posts Darkman. Perhaps it's that I'm such a visual learner but I still am un-clear on what exactly needs to be cut off to get these SRX rear ends to work in the V's.

darkman
06-02-13, 09:00 PM
Interesting posts Darkman. Perhaps it's that I'm such a visual learner but I still am un-clear on what exactly needs to be cut off to get these SRX rear ends to work in the V's.

I have not looked at one, but I gather that it becomes obvious once you have one in hand together with the drive shaft you are trying to attach to it.