AMSOIL DOMINATOR Coolant Boost
AMSOIL DOMINATOR Coolant Boost is a wetting-agent coolant additive that lowers surface tension in the cooling system to pull heat out of cylinder heads, blocks, and radiators faster. The formula is built around a proprietary tiered-surfactant technology and a corrosion-inhibitor package, and it is compatible with straight water, propylene glycol, ethylene glycol, and 50/50 antifreeze mixtures. DOMINATOR Coolant Boost is built for racers, autocross and track-day drivers, tow rigs working at altitude, and any engine running near its thermal limit.
Lower peak coolant temperatures under load
Higher liquid-to-metal contact moves heat out of the cylinder head and into the coolant more efficiently, which holds peak engine temperatures down when the engine is loaded. In dyno testing on a 350 cubic inch Chevy with an aluminum block and aluminum heads run at 4,500 rpm until coolant temperature stabilized, a 50/50 antifreeze/water baseline stabilized at 228 F (108.9 C) and straight water stabilized at 220 F (104.4 C). With DOMINATOR Coolant Boost added, the 50/50 mixture dropped 8 F (4.5 C) and the straight-water setup dropped 25 F (14 C).
Three-stage surfactant technology
DOMINATOR Coolant Boost uses three surfactants, each engineered to work in a different temperature range, so the wetting effect stays active as the coolant climbs from warm-up to peak operating temperature. Closer coolant-to-metal contact protects horsepower and reduces the risk of detonation, knock, and pre-ignition in tuned and high-compression engines.
Faster engine warm-up
In a controlled warm-up test, a V8 test engine was run at idle in a 30 F (-1 C) ambient with a 50/50 antifreeze/water mix and then again with DOMINATOR Coolant Boost added to the same mixture. Time to reach 120 F (49 C) dropped from 6.3 minutes to 3.2 minutes. Time to reach 180 F (82 C) dropped from 11.4 minutes to 5.3 minutes, an average warm-up improvement of 54 percent. Faster warm-up cuts the cold-start window where most engine wear occurs and shortens the time the engine spends in fuel-rich open-loop operation.
Aluminum-safe corrosion protection
Modern engines run aluminum cylinder heads, aluminum intake manifolds, and aluminum radiators, all of which corrode rapidly in untreated water. The Cast Aluminum Alloys Corrosion Test (ASTM D4340) heats a cast aluminum puck to 275 F (135 C) at 28 psi and exposes it to the test fluid for one week, with a 1.0 mg weight-loss limit required to pass. Cast aluminum in straight water with DOMINATOR Coolant Boost showed 0.06 mg weight loss against 3.97 mg for water alone, well inside the passing limit.
Six-metal corrosion protection
Cooling systems combine copper, solder, brass, steel, cast iron, and cast aluminum, and each metal has its own corrosion risk in degraded coolant. In the Corrosion Test in Glassware (ASTM D1384), six metal coupons were immersed in aerated coolant for 336 hours at 190 F (87.8 C), and DOMINATOR Coolant Boost in straight water held weight loss to 1 mg or less on every metal against ASTM limits of 10 to 30 mg. The Simulated Service Corrosion Test (ASTM D2570) extends that protection to 1,064 hours at 190 F under simulated service flow with the same result.
Compatible with all coolant types and water sources
DOMINATOR Coolant Boost is radiator-safe and works with ethylene glycol antifreeze, propylene glycol antifreeze, and straight-water race setups. It is compatible with distilled, bottled, and tap water, and it does not change the freeze point of an antifreeze mixture, so cold-climate vehicles keep their normal 50/50 protection while still gaining the wetting benefit.
Recommended applications and service intervals
Use DOMINATOR Coolant Boost in racing applications running straight water as coolant and in street, fleet, and powersports applications running antifreeze mixtures. Add the calculated dose by the cooling-system capacity listed in the service manual.
- Straight-water cooling systems (race, track day, autocross): 2 fl. oz. of DOMINATOR Coolant Boost per quart of total system capacity.
- Antifreeze and water mixtures (passenger vehicles, trucks, equipment): 1 fl. oz. of DOMINATOR Coolant Boost per quart of total system capacity.
- Service life in straight-water systems: drain, refill, and re-dose once per year.
- Service life in antifreeze mixtures: re-dose once per year or every 30,000 miles (48,280 km), whichever comes first, and follow the coolant manufacturer drain interval for the base coolant.
To install, make sure the engine is off and cool, confirm the cooling system is filled with the selected coolant, shake the bottle, pour the calculated dose into the radiator or expansion tank, start the engine, set the heater to high, and run for 15 minutes. DOMINATOR Coolant Boost is a finished additive and does not require a flush or a separate water wetter, and aftermarket coolant additives are not recommended for use alongside it.
Typical technical properties
| Property | Value |
|---|
| Product code | RDCB |
| Form | Liquid coolant additive |
| Treat rate, straight water | 2 fl. oz. per quart of system capacity |
| Treat rate, antifreeze mixture | 1 fl. oz. per quart of system capacity |
| Peak temperature reduction, straight water (350 CID dyno, 4,500 rpm) | 25 F (14 C) lower |
| Peak temperature reduction, 50/50 antifreeze/water (350 CID dyno, 4,500 rpm) | 8 F (4.5 C) lower |
| Warm-up time to 120 F at 30 F ambient (50/50 antifreeze/water with additive) | 3.2 min. vs 6.3 min. baseline |
| Warm-up time to 180 F at 30 F ambient (50/50 antifreeze/water with additive) | 5.3 min. vs 11.4 min. baseline |
| Cast Aluminum corrosion, ASTM D4340, weight loss (mg) | 0.06 (vs 3.97 water only, 1.0 mg pass limit) |
| Compatible water sources | Distilled, bottled, tap |
| Compatible coolant chemistries | Ethylene glycol, propylene glycol, straight water |
Order AMSOIL DOMINATOR Coolant Boost
DOMINATOR Coolant Boost is available in a 16 fl. oz. bottle (RDCBCN-EA) and a case of six 16 fl. oz. bottles (RDCBCN-CA). AMSOIL products are backed by the AMSOIL Limited Liability Warranty. Match the right coolant chemistry to the engine with the AMSOIL Coolant Guide, match the right product with the AMSOIL Vehicle Lookup Guide, then order AMSOIL DOMINATOR Coolant Boost.
Customer reviews
It just works great!
08 F150 with 165K miles on it. Can't remember when I last flushed the radiator. The overflow tank was looking not-so-good. I used the Amsoil flush, ran a bunch of water through the system, while the inside heater was on, and once everything was running clear, I emptied the radiator, engine and anything else I could. Installed the Amsoil coolant and warmed the engine up, topped it off and haven't had any issues since. I've only run it less than 500 miles, but Amsoil is begging me for a review, so here you go. The flush worked wonders. The coolant, we'll have to go more miles. so far, so good.
By Dave from Close to Austin TX. on July 18, 2026.
Great
Great dose the job
By Kyle from Cedar lake on April 29, 2026.
Would recommend this to a friend.
Engine Warms Up Faster and Heat is Hotter in Cabin
Does what it says it does. In the winter it warms up faster and looking forward to running cooler in the summer. Recently added to my maintenance routine on all 3 of my vehicles because I've been so impressed with all AMSOIL's products I've tried.
By Gary from South Carolina on March 30, 2026.
Would recommend this to a friend.
Read all 68 reviews
Frequently asked questions
What does DOMINATOR Coolant Boost do inside the cooling system?
DOMINATOR Coolant Boost is a wetting-agent additive. The tiered-surfactant package lowers surface tension between the coolant and the metal it touches, which increases liquid-to-metal contact in the cylinder head, block, and radiator. More contact transfers more heat per second, reducing warm-up time on cold starts and holding peak temperatures down under load.
Can DOMINATOR Coolant Boost be used in a race engine running straight water?
Yes. Straight-water race setups are the primary use case. Add 2 fl. oz. per quart of total cooling-system capacity, then drain, refill, and re-dose once per year. The corrosion-inhibitor package is what makes straight-water race coolant tolerable, with weight loss on all six common cooling-system metals held well inside ASTM D1384 and ASTM D2570 limits.
Is DOMINATOR Coolant Boost compatible with antifreeze already in the system?
Yes. DOMINATOR Coolant Boost is compatible with ethylene glycol and propylene glycol antifreeze and is designed to drop into an existing 50/50 mixture without changing the base coolant chemistry. Use 1 fl. oz. per quart of total system capacity for antifreeze mixtures and re-dose once per year or every 30,000 miles (48,280 km), whichever comes first.
Does DOMINATOR Coolant Boost replace antifreeze or provide freeze protection?
No. DOMINATOR Coolant Boost is a performance additive, not an antifreeze. It does not raise the boiling point or lower the freeze point of straight water on its own. Cold-climate vehicles still need an ethylene glycol or propylene glycol antifreeze mixed with water in the ratio listed in the service manual, and DOMINATOR Coolant Boost is added on top of that mixture.
Is DOMINATOR Coolant Boost safe for aluminum radiators and aluminum cylinder heads?
Yes. In the Cast Aluminum Alloys Corrosion Test (ASTM D4340), cast aluminum exposed to straight water with DOMINATOR Coolant Boost at 275 F (135 C) and 28 psi for one week recorded 0.06 mg of weight loss, against a 1.0 mg pass limit and 3.97 mg for water alone.
Will adding DOMINATOR Coolant Boost void a new vehicle warranty?
No. Using AMSOIL synthetic lubricants and additives does not void a new vehicle or equipment manufacturer warranty, and DOMINATOR Coolant Boost is covered by the AMSOIL Limited Liability Warranty. Continue to follow the vehicle manufacturer service schedule for the base coolant.
