Originally Posted by GTgears

It does more then that. Synchros require some friction to operate. The Redline LS additive may be making it too slippery for the synchros as well. The whole reason I don't care for the Redline gear oils themselves is that even their NS is too slippery. Keep using the SHC and skip the LSD additive. All it really does is make the LSD chatter less. It does not improve performance IMO. Regards, Matt Monson Guard Transmission LLC.