A Core deposit is a form of deposit you pay until returning your old part. If you don't have the core at the time of purchase, you must pay the core charge. That charge is refunded to you when you return the core.
The best warm weather demulsifier diesel fuel additive, DIESEL FIRE enhances all-around performance and helps you avoid expensive breakdowns. DIESEL FIRE demulsifies water, increases cetane up to 6 points, increases lubricity, and cleans fuel systems by removing deposits including those found in high pressure common rail engines.