: Amsoil Severe Gear for Rear Diff, still need Friction Modifier?



spearfish25
05-28-13, 10:07 AM
I'm planning to swap out the rear diff fluid with Amsoil Severe Gear. I've seen a couple places that suggest some of these LSD oils already have friction modifiers and don't need any additional additive. When you guys swap diff oil, are you still adding some friction modifier per GM specs or just using the new oil alone?

cruiser68
05-28-13, 01:09 PM
I run Severe Gear and I add the limited slip additive.

thebigjimsho
05-28-13, 01:45 PM
You MUST add modifier. Amsoil has said as such for our V2s. I ran without the first year with Amsoil and it howled. Sometime in 2010, Amsoil said to add. No more howl with it added...

spearfish25
05-29-13, 10:05 AM
You MUST add modifier. Amsoil has said as such for our V2s. I ran without the first year with Amsoil and it howled. Sometime in 2010, Amsoil said to add. No more howl with it added...

Sounds good. Modifier from GM and my Amsoil order arrive today. Love that I don't have to lift the back end to get at the diff. Plenty of room to slide under the car.

thebigjimsho
05-29-13, 12:29 PM
Sounds good. Modifier from GM and my Amsoil order arrive today. Love that I don't have to lift the back end to get at the diff. Plenty of room to slide under the car.

I have a driveway that slopes downward. I could back the V up onto ramps and have all the space this fatso ever needed...

spearfish25
07-24-13, 11:05 PM
I appreciate everyone's opinions but decided to ask Amsoil directly. Here is the reply:

*****
The Severe Gear line already has added friction modifier. Applications that require more than 4 oz of friction modifier may need additional product added if there is gear chatter.
*****

Since the manual only says to add 2.3oz of friction modifier if using GM fluids and draining with the drain plug, it would seem we don't need to add any modifier (unless you hear chatter afterwards, of course).

sykb47l
07-25-13, 10:07 AM
Mine needed it.

spearfish25
07-25-13, 10:14 AM
Mine needed it.

I may just put it in regardless. At least my clutch packs will last longer.

ENVIOUS V
07-31-13, 02:51 PM
This is what I'm running.
http://weaponxmotorsports.myshopify.com/collections/fluids/products/amsoil-severe-gear-75w-90-rear-diff-complete-kit

spearfish25
08-02-13, 07:35 AM
I puss'd out and just put the 70ml of modifier in. Nice and quiet.

miamictsv
08-02-13, 03:30 PM
I puss'd out and just put the 70ml of modifier in. Nice and quiet.
What is the part number for the modifier that you use? I may have to put some in mine. Thank you

spearfish25
08-03-13, 08:34 AM
http://www.amazon.com/dp/B0028CMPIS

OldRoadDawg
08-03-13, 01:50 PM
What is the part number for the modifier that you use? I may have to put some in mine. Thank you

http://www.cadillacforums.com/forums/2009-2013-cadillac-cts-v-general/267035-differential-failure-7136-miles-redux.html#post3060700
Forum member 'C66 Racing' used to be a vendor for AMSOIL products and was who I purchased my products from last August. Not sure on his status currently, but you could PM him.