2011-2016 Hyundai Genesis Coupe Brake Fluid Type and Flush Interval

By Core Brake Parts Tech Team — Circleville, OH warehouse

The 2011-2016 Hyundai Genesis Coupe takes brake fluid that meets SAE J1703 / FMVSS 116 DOT 3 or DOT 4, and the system holds roughly 0.7 to 0.8 quarts. Hyundai's printed schedule only calls for the fluid to be inspected every 7,500 miles or 6 months, so there is no factory mileage for a flush. A practical interval for a street car is every two years, and more often if you drive on track or run the Brembo cars hard.

Genesis Coupe brake fluid specs at a glance

These numbers come straight from the Genesis Coupe owner's manual's recommended lubricants and capacities table. The 2014 manual lists the same brake fluid entry as the earlier edition.

The manual accepts either grade, but DOT 4 is the better choice for this car. You need more than one bottle's worth for a full flush. The capacity figure is what sits in the system, and you push extra fluid through each bleeder until it comes out clean.

DOT 3 vs DOT 4: which one to buy

Both grades are glycol-based, and the manual lists both. The difference is heat tolerance. Federal standard FMVSS 116 sets these minimum boiling points:

The "wet" number is the boiling point after the fluid has taken on 3.7 percent water by volume. That is the number that matters on a car that is a few years old. The Genesis Coupe is a rear-drive sports coupe, and plenty of them see canyon runs, autocross and track days, so the extra margin of DOT 4 is worth having. For a car that will be tracked, choose a high-temperature DOT 4 and flush it before every event season.

DOT 3 and DOT 4 are both glycol fluids, so topping off one with the other will not cause an immediate problem. The usual advice from brake makers like Brembo is to pick one fluid and stick with it for the life of the car. Never add silicone-based DOT 5 to this system.

How often to flush the brake fluid

Hyundai's normal maintenance schedule for the Genesis Coupe lists brake fluid as an inspect item at every 7,500 miles or 6 months, all the way to 150,000 miles. It never lists a replacement. That leaves the owner to decide when the fluid is worn out.

Brake fluid wears out because it absorbs moisture. Brembo notes that the fluid pulls in water from the air through the brake hoses, and that the boiling point of fluid a few years old can be much lower than new. ADVICS gives a rough guide of about once a year for DOT 3 and about every two years for DOT 4, while stressing that the owner's manual comes first. Brembo's own recommendation is to change it every 2 to 3 years.

A sensible plan for a Genesis Coupe:

• Daily driver: Flush with DOT 4 every two years, whatever the mileage.
• Spirited street driving or R-Spec/Track trims: Every one to two years, and any time the pedal feels softer after hard use.
• Autocross or track days: Before each season at minimum, and bleed the calipers after any event where the pedal got long.
• Any brake job that opens the system: A caliper, hose or master cylinder replacement is the natural time to do a full flush.

Signs the fluid is overdue

• Dark fluid in the reservoir. New fluid is clear to light amber. Brown or black fluid is contaminated.
• Soft or sinking pedal after hard stops. Water-laden fluid can boil at the calipers and form vapor, which compresses. The pedal then goes long and firms up again once things cool.
• Brake warning light. The Genesis Coupe shares one warning light for the parking brake and low brake fluid. If it stays on with the parking brake released, check the level right away. A low level usually means worn pads or a leak.
• Heavy clutch or a clutch that does not release fully (manual cars). The hydraulic clutch draws from the same reservoir, so old fluid affects it too.
• Test strip or moisture-meter reading. A cheap test gives you a number to go on instead of guessing.

Do not just top off a low reservoir. Fluid level drops as the pads wear. If the level is low and the pads are fine, look for a leak at the calipers, hoses and lines before you drive the car.

How to flush a Genesis Coupe, and what to check while you are there

This is a moderate DIY job. The basic routine: remove old fluid from the reservoir, refill with fresh DOT 4, then bleed each caliper starting at the corner farthest from the master cylinder and working toward the closest, until clean fluid comes out. Keep the reservoir topped up the whole time so no air gets into the ABS unit. Every Brembo caliper has an inner and outer bleeder, and the air can hide behind either one, so bleed both.

On six-speed manual cars, bleed the clutch slave cylinder too. It shares the reservoir, and skipping it leaves old fluid in the clutch circuit. If the pedal is still soft after a careful manual bleed, the ABS modulator may need to be cycled with a scan tool. That is a job for a shop with the right equipment.

A flush is a good time to inspect the rest of the system:

• Rotors. Base cars use 12.6-inch front and 12.4-inch rear vented rotors with single-piston floating calipers. R-Spec and Track trims use Brembo four-piston calipers on 13.4-inch front and 13-inch rear vented rotors. If yours are grooved, heat-checked or below minimum thickness, the DBA 4000 Series T3 slotted front rotor for the 2011-2016 Genesis Coupe and the DBA 4000 Series T3 slotted rear rotor for the Track and R-Spec fit these cars.
• Hoses. Cracked or swollen rubber hoses make the pedal feel soft even with fresh fluid. Check the replacement brake hoses and braided brake lines for a firmer pedal.
• Calipers. Look for seepage at the piston seals and bleeders. See brake calipers if a seal is weeping.
• Master cylinder. A pedal that slowly sinks under steady pressure with no outside leak points to the master cylinder. See master cylinders.

Torque the bleeder screws and caliper bolts to the values in the factory service manual. Brake bleeders are small and easy to strip.

Frequently Asked Questions

What brake fluid does a Hyundai Genesis Coupe take?

The owner's manual calls for fluid that meets SAE J1703 and FMVSS 116 DOT 3 or DOT 4. DOT 4 is the better choice because it has higher minimum dry and wet boiling points.

How much brake fluid does the Genesis Coupe hold?

Hyundai lists 0.7 to 0.8 US quarts (0.7 to 0.8 liters). Buy more than that for a flush, since you run extra fluid through each bleeder, and through the clutch slave on manual cars.

Does Hyundai give a brake fluid change interval for the Genesis Coupe?

No. The normal maintenance schedule only says to inspect the brake fluid every 7,500 miles or 6 months. Most brake makers suggest replacing DOT 4 about every two years.

Can I use DOT 5.1 or DOT 5 in my Genesis Coupe?

Do not use silicone DOT 5. It is not listed for this car and does not mix with glycol fluid. The manual lists only DOT 3 and DOT 4, so stay with a quality DOT 4.

Is the clutch fluid the same as the brake fluid on a manual Genesis Coupe?

Yes. The engine bay has one shared brake/clutch fluid reservoir, so the clutch uses the same DOT fluid. Bleed the clutch slave cylinder when you flush the brakes.

Do the Brembo R-Spec and Track cars need different fluid?

No. They use the same fluid spec as the base car. Their four-piston calipers are often driven harder, though, so a high-temperature DOT 4 and a shorter flush interval make sense.

Sources

1. 2014 Genesis Coupe owner's manual (lubricants and capacities) - brake fluid 0.7 to 0.8 US qt, SAE J1703 / FMVSS 116 DOT-3 or DOT-4
2. Genesis Coupe owner's manual, recommended lubricants and capacities - same brake fluid capacity and DOT-3 or DOT-4 classification in the earlier manual
3. Genesis Coupe owner's manual, normal maintenance schedule - brake fluid, hoses and lines, pads, calipers and rotors inspected every 7,500 miles or 6 months; no fixed replace interval
4. 49 CFR 571.116 (FMVSS 116, motor vehicle brake fluids) - minimum dry and wet boiling points for DOT 3 and DOT 4
5. ADVICS: Brake fluid boiling points - wet boiling point is measured at 3.7 percent water; typical DOT 3 vs DOT 4 change timing; follow the owner's manual
6. Brembo: brake fluid for cars - fluid absorbs moisture through the brake lines; Brembo recommends replacement every 2 to 3 years
7. Hyundai 2013 Genesis Coupe press release - Brembo four-piston calipers with 13.4-inch front and 13-inch rear rotors on R-Spec and Track; base 12.6/12.4-inch rotors with single-piston calipers