Product Description
Build cleaner routing and durable flow on your diesel exhaust with the Diamond Eye 524521 45° elbow. This universal 4.0" T409 stainless, mandrel-bent elbow is perfect for tight turns on custom turbo-backs, downpipes, and tailpipe sections where space and longevity matter.
Fitment & Use
- Type: Universal fabrication part for 4.0" O.D. exhaust systems
- Material: T409 stainless steel (mandrel-bent)
- Typical Uses: Custom bends for turbo-back, mid-pipe, tailpipe, stacks, and repair work
- Pair With (Diamond Eye): 524520 4" 45° Aluminized Elbow, 524525 5" 45° Aluminized Elbow, matching 4" Diamond Eye straight & muffler-delete sections, 529021 4" 90° Stainless L-Bend
Why Diamond Eye
Diamond Eye’s U.S. manufacturing uses CNC mandrel bending for smooth interior radii and consistent wall thickness—translating to lower backpressure, cooler EGTs, and long service life.
Specifications
| Attribute | Value |
|---|---|
| Part Number | 524521 |
| Diameter | 4.0 inch |
| Bend | 45 degrees |
| Material | T409 stainless steel |
| UPC | 841963118100 |
| GTIN | 841963118100 (GTIN-12) |
| Package Size (W × H × L) | 9" × 9" × 26" |
| Shipping | Calculated at checkout |
| Warranty | 6-Year (Diamond Eye) |
| Prop 65 | WARNING: Cancer and Reproductive Harm — P65Warnings.ca.gov |
Cross-References / Alternatives (Diamond Eye Only)
- 524520 — 4" 45° Aluminized
- 524525 — 5" 45° Aluminized
- 529021 — 4" 90° Stainless L-Bend (see category listing)
FAQs
Is this a direct-fit part for my truck?
No—this is a universal fabrication elbow for any 4.0" exhaust system. Measure and mock-up before welding or clamping.
What stainless grade is used?
T409 stainless is used for durability and heat resistance on diesel applications.
Do I need lap-joint or butt-joint clamps?
Match the joint style you’re building. For pre-expanded/slip connections use a lap-joint clamp; for straight tube-to-tube joints use a butt-joint band clamp.
Will this change sound or power?
Mandrel bends reduce turbulence and restriction compared to crush bends, supporting smoother tone and potential flow gains when paired with a properly designed system.
