Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Science is NOT optional
 
rbogh901's Avatar
 
Join Date: Aug 2008
Location: West and further west
Posts: 1,977
Does friction modifier need to be used in LSD's?

Swepco 201 appears to be a given. My transmission still shifts well when the clutch is properly adjusted and I'd like to keep it that way.

"Friction Modifier (FM) is slippery stuff. The FM is in place to reduce LSD clutch chatter upon engagement. The amount needed is relative to the application and the age of the differential. In full race cars, you want the clutch to lock up nice and strong while not being so concerned with a little chatter. In high mileage (or worn) LSD cars, the clutches will be worn and need less FM to attain the desired effect. The downside, or catch-22, is that the syncros don't need or even like the FM. In most cars this is not a problem because the differential and transmission are separated and do not share the same lubricant. Our transaxled P-cars do share, so we must prepare for that.

FM options:

FM needs to be used in LSD cars, we know that. It's the amount that is variable. As a general rule, what comes out of the bottle is sufficient for most applications. Some folks will mix FM stuff with non-FM stuff (75W90NS and 75W90) until the desired effect of "no chatter" is attained... the reason for this being again, that syncros don't like FM."

__________________
PCA member since 1993
Old 11-03-2009, 08:06 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
GrantG's Avatar
 
Join Date: Jan 2005
Location: Denver, CO
Posts: 960
Garage
Swepco 201 does not need an additional FM with a 915 gearbox w/ LSD.
__________________
2022 GT3 Manual, 73 Carrera RS 2.9 Twin-Plug MFI Carbon Fiber Replica
Former: 18 GT3 Manual,16 Cayman GT4, 73 911S, Two 951S's, 996 C2, 993 C2, BMW 635CSi Euro, Ferrari 550 Maranello, 06 Evo IX w/ many mods
Old 11-03-2009, 08:10 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered
 
Roc Doc's Avatar
 
Join Date: Apr 2006
Location: Las Vegas, Hell
Posts: 212
It was my understanding that most full synthetic lube does not require a FM, but I recently bought some Mobil One from the local Ghetto Zone, and it is labeled LS, (for use with LS diffs). This was for a rear differential in my rockcrawler so it didn't make any difference to me.

I have some Amsoil that will be going in my 225k 915 (with factory LSD), and I am not planning on adding a FM. And yes, I have heard that 201 does not require a FM.

__________________
1976 911S Targa, Carrera bodywork, 3.2l engine.
Old 11-03-2009, 08:30 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Reply


 


All times are GMT -8. The time now is 08:39 AM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.