Summer+ Cetane Formula Diesel Fuel Additive: 1 Gallon with Accessories (HDPE Plastic Hand Pump and 2 Empty 4oz Bottles) Treats up to 2,560 Gallons

Awesome stuff! I didn’t even know the injectors were bad until I ran this feels like a completely new truck! Would not hesitate to buy it again.

Improve my mileage on our trip to Missouri in my 1998 Dodge ram 2500 4x4 with a Cummins 5.9 with 4.10 gears. 24 miles to a gallon of diesel fuel.

Does great to keep the diesel engine clean and lubricated. There are other cheaper brands but this stuff works the best. Would recommend getting something to measure the amounts out. I just use a 4 oz measuring glass.

Love this product. I have been using for 3 summers in my Mack triable dump truck. Truck seems to run smoother and get slightly better MPG when I use it. I dropped the stars from 5 to 4 because of the size of the small containers that come in the kit. I have been using the same small bottles to refill and carry with me for a couple years. I decided to buy the kit with the pump and bottles again this time to replace what I have because they are getting old and dirty. If I use these new ones I can only carry half the additive with me as before. I may have to just find a different container myself but if I had known this I wouldn’t have paid extra for the kit.

Bought the opti with cetane booster, use it for three weeks, this is a pic of my fuel water separator used in my 2017 Kenworth T-680, with a Cummins ISX rated at 475 horsepower, 462,500 on the motor, after 11,000 miles of use on this filter, which I changed today 6-12-25, the pic is worth a thousand words, normally, with the amount of soot buildup in these DPF trucks, this filter would be dark black as U can see it isn't, very surprised at this result, called the manufacturer about how often to use, they said every fillup, I started using it every other fill, it seems to work well, been driving for 15yrs never seen a product do this, used a lot of products, trial and error, for the money it does it's job!

I had an external water separator fail on my lift pump and the truck was dumping fuel even at idle. The CP4 Bosch fuel pump installed on my GMC is known for failure and Optilube saved me thousands in repairs. Getting on the highway and anytime I went past 1/4 throttle the truck would starve for fuel and fall on it's face. Optilube kept the pump from destroying itself while I gingerly drove it the rest of the way home. It's been 3,000 miles since the incident and the truck is running strong. I will be a customer for life!

You can buy this bottle for the same price on Amazon as from Optilube itself. I chose to buy through Amazon because I had a bonus with Amex for double points for Amazon purchases. As far as the product does it's great. I use it for every fill-up with my 2016 GMC Sierra 3500 Duramax. Works great seem to quiet down the injectors and I pull 10,000 pound trailers almost continuously. Love the product.

Seems like it’s pretty good stuff. The pump doesn’t leak and the little bottles are really handy for putting in the pocket of your door and they don’t leak either. A gallon or this stuff treats a bunch of fuel!

Love the product, noticeable difference in my ecodiesel. But the shipping cost to Canada is not worth it. There has to be a cheaper way. I probably will not buy again after this jug runs out. I will most likely try to find another brand of additive. If it was more available I would never switch.