Cold Weather Combo
Winter Flow + SOS Cold Weather Rescue. One kit covers both sides of winter.
$45.99
Winter prep
Diesel doesn't freeze. It waxes.
When it gets cold, wax in your diesel crystallizes and ends up in your fuel filter. Watch what it does to a filter, then get your truck ready before the first freeze.
- Free shipping on contiguous US orders of $99+
- 4.8 from 12,065 reviews
What actually happens
Temps drop
The wax that's naturally in diesel starts to crystallize.
It all ends up in one place
Your fuel filter catches it.
Fuel can't get through
The wax packs the filter and the engine starves for fuel.
So next time it won't start and it's 10 below, you'll know exactly where to look.
Wax or ice? Both stop at the filter.
The cloudy stuff in the video is wax, not ice. Water in the fuel can freeze too. Here's how to tell them apart.
Wax (the big one)
- Where it comes from
- Paraffin that's naturally in diesel
- What you see
- Cloudy fuel, a waxy, clogged filter
- What it does
- Plugs the filter so fuel can't get through
- What Winter Flow does
- “Prevents diesel fuel from gelling and waxing in freezing temperatures.”
Ice (the other one)
- Where it comes from
- Water that gets into the fuel
- What you see
- Ice in the filter or water separator
- What it does
- Blocks fuel flow at the filter
- What Winter Flow does
- “De-ices fuel filters before ice can cut off fuel flow.”
Two moves before the first freeze
Move 1
Treat the fuel
Pour Winter Flow 24/7 in at every fill-up, starting before the first freeze and running till spring.
Move 2
Start winter on a fresh filter
If your filter is already partway loaded, it has less room left before wax plugs it. Swap it before the cold, not on the side of the road.
Shop by truck
Pick your engine, then your years. You'll get the filter kit that fits, with Winter Flow ready to add.
2. Your years
Most popular for Ram owners
Your total
This kit is sold out right now. Leave your email and we'll tell you the day it's back. You can still treat your fuel today.
This kit is sold out right now. Leave your email and we'll tell you the day it's back. You can still treat your fuel today.
Your total
Your total
Your total
Your total
Your total
Your total
Your total
Your total
This kit is sold out right now. Leave your email and we'll tell you the day it's back. You can still treat your fuel today.
Your total
6.6L · 2019
2019 Duramax trucks came two ways, and each takes a different kit. Search by your truck and we'll show the one that fits.
Search by my truck
Your total
Your total
Fits 3.0L 2020-2023
Jeep Wrangler/Gladiator 3.0L + Ram 1500 3.0L EcoDiesel Filter Kit 2020-2023
$77.99
Your total
Your total
Winter add-ons
Winter Flow 24/7 Diesel Treatment + Cetane Boost
16 oz. Treats up to 200 gallons of diesel.
$23.99
Prevention Pair
Winter Flow + DEF Guard.
$36.99
Full Winter Stack
Winter Flow + DEF Guard + SOS. It covers fuel, DEF, and rescue in one kit.
$59.99
How much to pour
Winter Flow 24/7, at every fill-up through the cold months.
- Standard2 oz per 25 gallonsProtects down to 15°F (-9°C)
- Performance Boost4 oz per 25 gallonsFor below 0°F or sustained severe cold
gallons
Type your tank size to get ounces per fill.
Dual-chamber bottle has a built-in measuring cup, no extra tools needed.
Always follow the dosage directions on the product label.
First Freeze
When does your first freeze hit?
Enter your zip for the typical first freezing night where you are.
Already gelled?
Truck won't start? Keep SOS in the cab.
Winter Flow is the prevention. SOS Cold Weather Diesel Rescue Treatment is for the morning the cold wins anyway.
- “Reliquefies gelled fuel, de-ices frozen filters”
- “Rated To -25°F”
One 16 oz bottle of SOS treats up to 50 gallons. That's a different dose from Winter Flow, so follow its own label.
Want both? The Cold Weather Combo pairs Winter Flow with SOS. Get the combo, $45.99
Both moves, one owner
“Right before the 2 week polar vortex and snow storm I changed my oil and filter and fuel filter. Added a bottle of 24/7 and with sub zero temps my 5.9 Cummins fired up a lot easier on cold mornings. Will buy more for sure”
Questions owners ask
Does diesel freeze?
Not solid. The wax in it crystallizes when it gets cold and collects in the fuel filter until fuel can't get through.
Why does it always stop at the filter?
The filter's job is catching what shouldn't reach your injectors. Wax crystals are big enough to get caught, so that's where they pile up. This happens with any brand of filter.
How cold does it have to get?
Diesel begins waxing at 32°F, so treat the fuel before temperatures drop, not after.
How much Winter Flow do I use?
2 oz per 25 gallons for protection down to 15°F. 4 oz per 25 gallons below 0°F. One 16 oz bottle treats up to 200 gallons.
Can I use it in my tractor or semi?
Yes. Winter Flow is safe for all diesel engines including pickups, semis, farm equipment, and off-road machinery.
My truck already gelled. Now what?
That's what SOS Cold Weather Diesel Rescue Treatment is for. It reliquefies gelled fuel, de-ices frozen filters and is rated to -25°F. Shop SOS