Skip to product information
1 of 1

Flex

Flex 4JJ3 Intercooler | D-MAX MU-X BT-50 | 80 PSI | Bolt-On

Flex 4JJ3 Intercooler | D-MAX MU-X BT-50 | 80 PSI | Bolt-On

Regular price $1,708.00 NZD
Regular price $1,773.00 NZD Sale price $1,708.00 NZD
Sale Sold out

Taxes excluded. Shipping calculated at checkout.

Quantity
Normally Ships in 0-2 Business Days

4JJ3 Bolt-On Intercooler Upgrade – 2020+ D-MAX / BT-50

FLEX Monoblock Performance Intercooler | Direct Bolt-On | 80 PSI Rated

⚡ Flex Ultimate Performance Monoblock Core 🔥 80 PSI Rated 💪 Direct Bolt-On ✅ 💳 Afterpay • Humm • Klarna • Zip 🚚 Free Express Shipping AU

Step up your cooling game with this heavy-duty FLEX Monoblock Intercooler – the perfect bolt-on upgrade for tuned or heavy-use D-MAX, MU-X, and BT-50 builds.


🔧 Key Features
  • Direct bolt-on fitment – note - some models may require IAT boss welded on.
  • One-piece monoblock casting – stronger and leak-free
  • Handles up to 80 PSI of boost – built for serious use
  • Improves charge cooling – lowers IATs and reduces heat soak
  • 620 × 252 × 63.5mm core – optimized for 4JJ3 platform
  • OEM-style mounting – uses factory locations and routing

📐 Technical Specifications
  • Brand: FLEX
  • Core size: 620 × 252 × 63.5mm
  • Core Type: Monoblock one-piece casting
  • Boost Rating: 80 PSI
  • Suits: 2020+ Isuzu D-MAX, MU-X & Mazda BT-50 (pre-facelift)

🔧 Vehicle Compatibility
  • Isuzu D-MAX – 4JJ3-TCX (2020+)
  • Isuzu MU-X – 4JJ3-TCX (2020+)
  • Mazda BT-50 – 4JJ3-TCX (2020+, pre-facelift)

✅ Direct OEM replacement: Uses factory mounting points and hose locations. No cutting or welding required.

⚠️ FACELIFT MODELS: For facelift vehicles, confirm cooler mounting and outlet positions or message us with your VIN.


📦 What's Included
  • FLEX Monoblock Intercooler – 80 PSI rated core

Direct replacement for factory intercooler. Reuse factory mounting hardware and clamps.


🛠️ Installation Notes
  • Direct bolt-on – uses factory mounting locations
  • OEM hose routing – works with factory or aftermarket piping
  • No cutting or fabrication required for standard installations
  • Aftermarket piping kits that relocate outlets may require minor adjustment
  • Professional installation recommended
  • Check all clamps and connections for proper sealing

💡 Why Upgrade?

Whether you're towing, touring, or chasing power gains, this intercooler delivers the airflow consistency and durability modern turbo diesels demand.

Benefits:

  • Lower intake air temps – denser air charge for more consistent power
  • Reduced heat soak – sustained performance under load
  • Monoblock strength – superior reliability vs multi-piece designs
  • 80 PSI rating – handle extreme boost on tuned builds
  • Perfect for towing – consistent cooling on long highway runs

⏱️ Stock & Lead Time

In-stock items ship same/next business day.

⚠️ LEAD TIME: If out of stock, expect ~2–3 weeks from Thailand stock. Contact us if you're on a deadline.


💳 Payment & Shipping Options
  • 💸 Buy Now, Pay Later: Afterpay, Humm, Klarna & Zip available
  • ✈️ Free Express Shipping Australia-Wide
  • 📦 Fast, trackable dispatch from Australian warehouse

⚠️ Legal Notice

For off-road / competition use only. Intercooler modifications may affect compliance. Check local regulations before purchase.


❓ Frequently Asked Questions

Q: Is this a true bolt-on intercooler?

A: Yes — designed to replace the factory cooler on 2020+ D-MAX/MU-X and BT-50 (pre-facelift) with no cutting or welding when used with OEM mounting and hose locations.

Q: Do I need a tune after installing?

A: No tune is strictly required. A tune can extract more benefit by optimising boost, fueling and timing to take advantage of the lower IATs.

Q: What boost pressure can it handle?

A: The FLEX monoblock core is rated up to 80 PSI. Actual safe boost depends on your turbo, clamps/couplers, and overall setup quality.

Q: Will it work with my existing piping?

A: Yes — it's built around OEM routing. Aftermarket piping kits that relocate outlets may require minor adjustments.

Q: Which models/years does it fit?

A: 2020+ Isuzu D-MAX, MU-X and Mazda BT-50 (pre-facelift). For facelift vehicles, confirm cooler mounting and outlet positions or message us with your VIN.

Q: What's the typical lead time?

A: In-stock items ship same/next business day. If out of stock, expect ~2–3 weeks from Thailand stock. Contact us if you're on a deadline.

Q: What's the advantage of monoblock construction?

A: One-piece monoblock casting provides superior strength and reliability under high boost compared to multi-piece designs. Less prone to leaks or failure.

Q: Will this improve my performance?

A: Cooler intake air temps mean denser air charge, which supports more consistent power output, especially on tuned vehicles or under sustained load (towing, highway runs).

Q: Do I need to upgrade my clamps or piping?

A: For high-boost applications (40+ PSI), consider upgrading to quality silicone hoses and heavy-duty T-bolt clamps for maximum reliability.

Q: Is this compatible with aftermarket turbos?

A: Yes — the 80 PSI rating makes it perfect for use with aftermarket turbos like the Flex F55 or other performance upgrades.


⚡ KEEP YOUR 4JJ3 COOL

FLEX monoblock intercooler. 80 PSI rated. Direct bolt-on. Cooler IATs. Reduced heat soak. Perfect for towing & performance.

Disclaimer: Common Rail Cowboys is not affiliated with Isuzu Motors or Mazda Motor Corporation. Installation should be performed by a qualified technician. Proper installation and fitment verification are the buyer's responsibility.

View full details