Exhaust Tube – Fits MerCruiser V6 & V8 (Replaces Mercury 32-807458T)
Exhaust Tube – Fits MerCruiser V6 & V8 (Replaces Mercury 32-807458T) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
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Exhaust Tube – Fits MerCruiser V6 & V8 (Replaces Mercury 32-807...
Exhaust Tube – Fits MerCruiser V6 & V8 (Replaces Mercury 32-807458T) is backordered and will ship as soon as it is back in stock.
Product Details
This Marine Exhaust Tube is designed for select MerCruiser/Mercury V6 and V8 stern drive engines, including 4.3L Gen+ models from 1998 and later. It serves as a crucial component for routing exhaust gases safely and efficiently.
It is a direct replacement for Sierra 18-2770, Mallory 9-72804, and Mercury 32-807458T, offering a reliable aftermarket alternative.
- Engineered for direct-fit installation.
- Constructed with durable metal housing to withstand the marine environment.
- Covered by a Limited Lifetime Warranty for peace of mind.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 32-807458T |
| Sierra | 18-2770 |
| Mallory | 9-72804 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For MerCruiser models, always verify your engine's serial number is within the specified range for accurate fitment.
| Brand | Model | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| MerCruiser | 4.3L (Gen+) 2 BBL GM 262 V-6 | 4-Stroke | 1998 | 32-807458T | Serial #0L010044-0M614999 |
| MerCruiser | 4.3L EFI (Gen+) TBI GM 262 V-6 | 4-Stroke | 32-807458T | Serial #0L012009-0L618999 | |
| MerCruiser | 4.3L EFI (Gen+) TBI GM 262 V-6 | 4-Stroke | 32-807458T | Serial #0L619000-0M322780 | |
| MerCruiser | 4.3LH (Gen+) 4 BBL GM 262 V-6 | 4-Stroke | 1998 | 32-807458T | Serial #0L010044-0M614999 |
| MerCruiser | 4.3LX (Gen+) 2 BBL GM 262 V-6 | 4-Stroke | 1996–1997 | 32-807458T | Serial #0F803000-0K999999 |
| MerCruiser | 4.3LXH (Gen+) 4 BBL GM 262 V-6 | 4-Stroke | 1996–1997 | 32-807458T | Serial #0F803114-0K999999 |
| MerCruiser | 262 MAG (TBI)(Gen+) | 4-Stroke | 32-807458T | Serial #0F803800-0K999999 |
Technical Specs
- Product Type
- Exhaust Tube
- Installation
- Direct replacement
- Fuel Type
- Gasoline
- Housing Material
- Metal
- Dimensions
- Approximately 5.5 × 5.5 × 5 inches (139.7 × 139.7 × 127 mm)
- Weight
- 0.97–1.04 lbs (0.44–0.47 kg)
- Warranty
- Limited Lifetime (Sierra brand)
- Country of Origin
- Italy (Sierra part)
What’s in the Box
- 1 x Exhaust Tube (32-807458T)
Installation Notes
- Disconnect the battery and allow the engine to cool completely.
- Gain clear access to the exhaust manifold and riser assembly.
- Carefully disconnect any hoses or sensors attached to the old exhaust tube.
- Unbolt and remove the old, corroded, or damaged exhaust tube.
- Thoroughly clean the mating surfaces on the exhaust manifold and riser.
- Position the new exhaust tube and align it correctly.
- Install new gaskets (sold separately) where required.
- Tighten all bolts to the manufacturer's recommended torque specifications.
- Reconnect any hoses or sensors that were removed.
- Reconnect the battery, start the engine, and check for any exhaust or water leaks.
Troubleshooting & FAQ
How do I confirm this exhaust tube fits my specific MerCruiser engine?
The most reliable method is to check your engine's serial number. Compare it against the serial number ranges listed in the 'Engine & Model Compatibility' table. If your serial number falls within one of those ranges, this part should fit.
What are the common signs that my exhaust tube needs replacing?
Symptoms of a failing exhaust tube include water leaking into the engine cylinders (hydrolock), engine overheating, visible corrosion or cracks on the tube, and a noticeable exhaust leak sound from the engine compartment.
Is this a direct replacement for the original Mercury part 32-807458T?
Yes, this is a direct-fit aftermarket replacement for OEM part number 32-807458T. It is also an interchange for Sierra 18-2770 and Mallory 9-72804.
What tools will I need for installation?
You will typically need a socket set, torque wrench, gasket scraper or wire brush for cleaning surfaces, and potentially a sealant appropriate for marine exhaust applications. New gaskets are highly recommended.
Can I install this part myself?
While many boat owners with mechanical experience can perform the installation, we recommend professional installation to ensure it is done correctly, preventing potential water leaks that could cause catastrophic engine damage.
How often should this part be inspected?
It's good practice to inspect exhaust components annually, especially in saltwater environments. In freshwater, inspection every 2-3 years may suffice. Replace immediately if you see signs of significant corrosion, cracking, or leaks.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
Payment & Security
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