★ Plus Grade · Higher BP than Standard DOT 4
Sinolook DOT 4+ Brake Fluid
Premium DOT 4 hydraulic fluid with higher dry and wet boiling points than standard DOT 4. Engineered for modern ABS / ESP vehicles operating under heavier thermal loads.
- Dry boiling point 260 °C · Wet boiling point 165 °C
- Certified to FMVSS 116, ISO 4925 Class 4, SAE J1703, GB HZY4
- Independently tested at ABIC Testing Laboratories (USA)
- Available bulk, drum, IBC and retail packaging — OEM & private label welcome
260 °C
Dry Boiling Point
165 °C
Wet Boiling Point
Class 4+
Higher than ISO Minimum
25 yrs
Manufacturing Experience
Product Overview
DOT 4+ Brake Fluid
DOT 4+ brake fluid sits between standard DOT 4 and DOT 5.1 — same ISO 4925 Class 4 classification, but with dry and wet boiling points pushed well above the regulatory minimums. It is the upgrade path of choice for modern vehicles with ABS and ESP operating in warm climates, heavy traffic, or moderately performance-oriented driving.
Manufactured at our IATF 16949:2016 certified plant in Nan'an, Fujian, Sinolook DOT 4+ brake fluid meets all four major international standards: FMVSS 116, ISO 4925 Class 4, SAE J1703, and GB 12981 HZY4 — with margins of 30 °C dry / 10 °C wet above the ISO Class 4 minimum.
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Higher boiling points than DOT 4
Typical dry ERBP of 260 °C (vs 250 °C for standard DOT 4) and wet ERBP of 165 °C (vs 160 °C). Stronger resistance to brake fade under sustained heavy braking.
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Same chemistry, fewer compromises
Synthetic glycol-ether blend — identical compatibility profile to DOT 4. Direct upgrade fill with no operational difference except higher thermal margin.
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Fully backward compatible
Mixable with DOT 3, DOT 4 and DOT 4 LV from any manufacturer meeting FMVSS 116 or ISO 4925.
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For warmer climates & heavier duty
Designed for ABS / ESP vehicles operating in hot climates, mountain regions, towing duty, or aggressive city driving.
Technical Specifications
Sinolook DOT 4+ — typical production values
Enterprise typical values from current production batches. Every shipment is supplied with a Certificate of Analysis (COA) listing the batch-specific results. Independent ABIC test reports against FMVSS 116, ISO 4925, and SAE J1703 are available on request.
| Property | Test method | Typical value | ISO 4925 Class 4 min. |
|---|---|---|---|
| Appearance & Chemistry | |||
| Appearance | Visual | Clear, transparent | Free of suspended matter |
| pH value | ISO 4925 §6.3 | 7.9 | 7.0 – 11.5 |
| Boiling Point | |||
| Equilibrium reflux boiling point (Dry ERBP) | ISO 4925 §6.2 | 260 °C | ≥ 230 |
| Wet equilibrium reflux boiling point (Wet ERBP) | ISO 4925 §6.2.6 | 165 °C | ≥ 155 |
| Kinematic Viscosity | |||
| Viscosity at −40 °C | ISO 4925 §6.1 | 1,200 mm²/s | ≤ 1500 |
| Viscosity at 100 °C | ISO 4925 §6.1 | 2.0 mm²/s | ≥ 1.5 |
| Corrosion (120 h @ 100 °C ± 2 °C, mg/cm²) | |||
| Tinned iron / Steel / Cast iron | ISO 4925 §6.5 | Within tolerance | ±0.2 |
| Aluminium | ISO 4925 §6.5 | Within tolerance | ±0.1 |
| Brass / Copper / Zinc | ISO 4925 §6.5 | Within tolerance | ±0.4 |
| Rubber Compatibility (120 °C, 70 h) | |||
| SBR — hardness change (IRHD) | ISO 4925 §6.10 | Within tolerance | ≤ −15 |
| SBR — volume increase | ISO 4925 §6.10 | Within tolerance | 1 – 16% |
| EPDM — hardness change (IRHD) | ISO 4925 §6.10 | Within tolerance | ≤ −15 |
| EPDM — volume increase | ISO 4925 §6.10 | Within tolerance | 0 – 10% |
Typical values from production batch. Highlighted figures indicate margin above the ISO 4925 Class 4 minimum requirement. Complete test reports — including fluidity, water tolerance, oxidation and stroking — issued per shipment by ABIC Testing Laboratories.
Recommended Applications
Where Sinolook DOT 4+ brake fluid is used
DOT 4+ is positioned for specific application profiles where its combination of boiling points, viscosity and chemistry delivers measurable advantages over standard grades.
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Performance & sport sedans
Modern ABS / ESP-equipped cars with sportier driving demands than standard daily commuters.
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Mountain & alpine driving
Sustained downhill braking generates extreme heat in the caliper assembly — DOT 4+ resists vapor lock far better than standard DOT 4.
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Hot & humid climates
Tropical and equatorial regions where ambient temperature accelerates wet-ERBP degradation in standard DOT 4.
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Light commercial & service vehicles
Delivery vans, taxis, ride-share vehicles operating high duty cycles where higher boiling points extend safe service interval.
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Sport & touring motorcycles
Sport-touring and adventure motorcycles where standard DOT 4 may be marginal under spirited riding.
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Aftermarket upgrade fill
A simple, safe upgrade for vehicles originally specified for DOT 3 or DOT 4 where the owner wants more thermal margin.
Note: Always check the brake fluid reservoir cap on the master cylinder for the manufacturer's specification. Never use a fluid grade lower than specified. Glycol-ether brake fluids must never be mixed with DOT 5 silicone.
B2B Capability
Flexible packaging, OEM & global supply
Sinolook DOT 4+ is supplied in every commercial format — from 250 ml retail bottles for the aftermarket through to ISO tanks for high-volume lubricant blenders and OEM brake-system suppliers.
SERVICE 01
OEM & private label
Custom label design, custom bottle / drum colors, dedicated SKU codes. Artwork approval to first shipment in 25 – 35 days.
SERVICE 02
Retail & bulk packaging
250 ml · 500 ml · 1 L retail bottles · 5 L, 20 L, 200 L drums · 1,000 L IBC totes · flexitank · ISO tank.
SERVICE 03
Global logistics
Direct shipment ex Xiamen, Hong Kong or Singapore. FOB / CIF / DDP terms. UN 1992 / IMDG-compliant export packing.
SERVICE 04
Documentation per shipment
Technical Data Sheet (TDS), Safety Data Sheet (SDS), Certificate of Analysis (COA), AMECA notification, certificate of origin and CIQ documents.
Learn More
Brake fluid resources
In-depth guides on brake fluid chemistry, standards, and selection — written by our technical team.
Reference
Types of Brake Fluid Explained: DOT 3, 4, 4+, 5, 5.1, HZY6, Class 7
Every brake fluid grade compared — composition, boiling points, applications and selection chart.
Technical
Brake Fluid Boiling Point: Dry vs Wet, Why It Matters
How the ERBP test works, why fluid absorbs moisture, and how brake fade actually happens.
Standards
Brake Fluid Standards: FMVSS 116, ISO 4925, SAE J1703 & GB 12981
A B2B reference on the four major brake fluid standards and how they map to OEM specifications.
Compatibility
Can You Mix Brake Fluids? DOT 3, 4, 5.1 & DOT 5 Compatibility
A complete compatibility matrix — which combinations are safe, which will destroy your brake system.
EV / Hybrid
Brake Fluid for EVs & Hybrids: Why Low-Viscosity Matters
Regenerative braking, brake-by-wire, and why electrified vehicles need low-viscosity high-performance fluid.
Service Interval
How Often Should You Change Brake Fluid?
Manufacturer intervals, climate impact, and when symptom-based replacement makes sense.
FAQ
Frequently asked questions
What is DOT 4+ brake fluid?
DOT 4+ is a premium DOT 4 grade brake fluid that exceeds the ISO 4925 Class 4 minimum dry and wet boiling points by significant margins. Sinolook DOT 4+ has a dry ERBP of 260 °C (vs 230 °C minimum) and a wet ERBP of 165 °C (vs 155 °C minimum). It is fully compatible with standard DOT 4 and serves as a direct upgrade for higher thermal performance.
What is the difference between DOT 4 and DOT 4+?
Both meet ISO 4925 Class 4 requirements, but DOT 4+ delivers higher boiling points (Sinolook DOT 4+: 260 °C dry / 165 °C wet vs DOT 4: 250 °C / 160 °C). Both have similar low-temperature viscosity. DOT 4+ is recommended where the brake system faces heavier thermal loads — hot climates, mountain driving, or performance use.
Is DOT 4+ the same as DOT 4 LV?
No. DOT 4+ focuses on higher boiling points; DOT 4 LV focuses on lower low-temperature viscosity. Both are ISO 4925 Class 4. Some products marketed as "DOT 4 Super" or "DOT 4 Long Life" combine both improvements — see our DOT 4 LV / DOT 4+ PLUS for that combination.
Can I use DOT 4+ in a vehicle originally filled with DOT 4?
Yes — DOT 4+ is fully backward compatible with DOT 4 and DOT 3. No system flush is required when topping up or replacing DOT 4 with DOT 4+. The upgrade is safe and only improves the thermal performance of the brake system.
Does Sinolook DOT 4+ meet OEM specifications?
Sinolook DOT 4+ meets FMVSS 116, ISO 4925 Class 4, SAE J1703, and GB 12981 HZY4 — the four major international brake fluid standards. Specific OEM cross-reference (e.g. ESI 6.7, ISO 4925 Class 6 equivalence) is available on request — contact sales@sinolook.com with your target specification.
Can I mix Sinolook DOT 4+ with other glycol-ether brake fluids?
Yes. Sinolook DOT 4+ is fully compatible with all other glycol-ether based brake fluids — DOT 3, DOT 4, DOT 4+, DOT 4 LV, DOT 5.1, HZY6 and Class 7 — from any manufacturer meeting FMVSS 116 or ISO 4925. It must never be mixed with DOT 5 silicone brake fluid, which is chemically incompatible and will damage seals.
What standards does Sinolook DOT 4+ meet?
Sinolook DOT 4+ brake fluid is certified to four major international standards:
• US FMVSS 116
• ISO 4925:2020 — Class 4
• SAE J1703
• GB 12981 HZY4 — China national standard
Independent test reports are issued by ABIC Testing Laboratories, Inc. in Fairfield, New Jersey, USA. Manufacturing operates under IATF 16949:2016 and ISO 9001:2015 quality systems.
• US FMVSS 116
• ISO 4925:2020 — Class 4
• SAE J1703
• GB 12981 HZY4 — China national standard
Independent test reports are issued by ABIC Testing Laboratories, Inc. in Fairfield, New Jersey, USA. Manufacturing operates under IATF 16949:2016 and ISO 9001:2015 quality systems.
What is the shelf life of unopened DOT 4+?
Sealed Sinolook DOT 4+ has a shelf life of 24 months from the production date when stored in original containers, away from direct sunlight, at 5 – 30 °C. Once opened, glycol-ether brake fluid begins absorbing atmospheric moisture (hygroscopy), which lowers its boiling point — opened containers should be used within 12 months.
What is the minimum order quantity for Sinolook DOT 4+?
Standard MOQ is 1 × 20'FCL, approximately 18–20 metric tons depending on packaging configuration. Smaller trial orders may be accepted for OEM and private-label customers. Bulk shipment in flexitank or ISO tank is available for orders 20 tons and above.
Does Sinolook offer OEM and private-label DOT 4+?
Yes. Sinolook offers full OEM and private-label service: custom label design, custom bottle and drum colors, custom packaging sizes from 250 ml to 200 L, and bulk supply. Lead time is typically 25 – 35 days from artwork approval. Contact sales@sinolook.com with your label artwork and packaging requirement.
Source DOT 4+ from a 25-year manufacturer
Tell us your packaging requirement, annual volume, and destination port. We'll respond within 24 hours with technical specs, pricing, and logistics options.
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📧 sales@sinolook.com
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