Limited Slip Additive with Synthetic Lube? (Page 1/1) Scottzilla79 NOV 24, 05:22 PM Hi Everybody, I have a 96 Roadmaster Wagon with a limited slip rear end. Manual calls for conventional fluid and LSD additive but I bought some Mobil 1 fluid for it that says its good for a limited slip but I'm wondering if I still should use the additive or not. Thanks in advance. carnut122 NOV 24, 06:49 PM I'm thinking you still need the additive. I don't think it would hurt anything to put it in there, but leaving it out might. Tony Kania NOV 25, 10:32 AM Hey Scott! Put the additive in. It is for the clutch packs, and will keep them from constantly slipping. Scottzilla79 NOV 25, 06:11 PM K thanks guys I will definitely put it in. HoMiE_TeLeFrAgGeD NOV 25, 07:11 PM I put the additive in all my rear ends. Its never gonna hurt thats for sure.