Diesel 911 does not prevent fuel gelling – use Diesel Fuel Supplement +Cetane Boost (in the white bottle) as a preventive measure to keep fuel from gelling. Diesel 911 and Diesel Fuel Supplement +Cetane Boost are compatible in diesel fuel and may be used at the same time. Having Diesel 911 on hand for winter emergency use is always a good idea.
https://www.amazon.com/Power-Service-08080-06-Diesel-Additive/dp/B001JT3GXO

