Edmac: Trusted Since 1948. For over 75 years, Edmac has been a go‑to source for high‑quality industrial lubrication solutions. With more than $10 million in inventory across our strategically located warehouses in North Carolina, California, and Oregon, we're ready to deliver the compressed air products you need – fast. Edmac offers a direct replacement for Gardner Denver AEON 4000 Compressor Lubricant (28H57), a widely used OEM fluid trusted for dependable rotary screw compressor performance. Your search ends here. Edmac proudly offers Roto SYN All Purpose 46 – a premium, partial-synthetic hydrocarbon-based compressor lubricant engineered to meet or exceed OEM specifications. Roto SYN All Purpose 46 is a direct replacement for Gardner Denver AEON 4000 28H57, delivering strong thermal stability, wear protection, and long-lasting lubrication in demanding rotary screw compressor environments. Designed for clean operation and extended service intervals, it helps reduce varnish formation, protect internal components, and maintain consistent performance under high-temperature and heavy-load operating conditions.