Lower Unit Seal Kit – Fits Suzuki DF200, DF225, DF250, DF300 (Replaces 25700-98J00, 25700-98J01)
Lower Unit Seal Kit – Fits Suzuki DF200, DF225, DF250, DF300 (Replaces 25700-98J00, 25700-98J01) is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Lower Unit Seal Kit – Fits Suzuki DF200, DF225, DF250, DF300 (Repla...
Product Details
This aftermarket Lower Unit Seal Kit is designed to restore the gear case integrity on a range of Suzuki outboard motors. It provides a direct-fit solution for Suzuki DF200, DF225, DF250, DF250S, and DF300 four-stroke engines manufactured from 2004–2011 and onward.
It serves as a direct replacement for Suzuki OEM part numbers 25700-98J00 and 25700-98J01, and interchanges with Sierra aftermarket part 18-8386.
- Engineered to meet or exceed original equipment specifications.
- Kit contains all necessary seals for a complete lower unit service.
- Professional installation is recommended for optimal performance and longevity.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket suppliers.
| Brand | Part Number | Notes |
|---|---|---|
| Suzuki Marine | 25700-98J00 | Original OEM part number. |
| Suzuki Marine | 25700-98J01 | Supersedes 25700-98J00. |
| Sierra | 18-8386 | Aftermarket cross-reference. |
Engine & Model Compatibility
Confirm your engine model and year in the table below to ensure accurate fitment.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Suzuki | DF200 | 200 | 4-Stroke | 2004–2011+ | 25700-98J00/98J01 | |
| Suzuki | DF225 | 225 | 4-Stroke | 2004–2011+ | 25700-98J00/98J01 | |
| Suzuki | DF250 | 250 | 4-Stroke | 2004–2011+ | 25700-98J00/98J01 | |
| Suzuki | DF250S | 250 | 4-Stroke | All Years | 25700-98J00/98J01 | |
| Suzuki | DF300 | 300 | 4-Stroke | 2007–2011+ | 25700-98J00/98J01 | Includes DF300T and DF300Z variants. |
| Suzuki | DF300AP | 300 | 4-Stroke | All Years | 25700-98J00/98J01 | Compatible with DF250SS/300AP models. |
Technical Specs
- Product Type
- Lower Unit Gear Case Seal Kit
- Weight
- 0.45 kg (1 lb)
- Dimensions
- 7.13″ L × 6.0″ W × 1.5″ H
What’s in the Box
- Complete Lower Unit Gear Case Seal Kit
Installation Notes
For safe and effective installation, professional service is strongly recommended. The process requires specialized tools to press-fit seals and properly pressure/vacuum test the gear case. Always refer to your engine’s official service manual for detailed procedures and torque specifications. Improper installation can lead to gear lube contamination, bearing failure, and catastrophic damage.
Troubleshooting & FAQ
How do I know if this seal kit fits my Suzuki outboard?
This kit is designed for Suzuki DF200-DF300 series four-stroke outboards from 2004/2007 through 2011 and later years. The most reliable way to confirm fitment is to match your engine's original part number to 25700-98J00 or 25700-98J01. Use the compatibility table on this page to check your specific model and year range.
What are common signs of failing gear case seals?
The most common sign is "milky" or cloudy gear lube, which indicates water intrusion. You may also find gear oil leaking from the propeller shaft or weep holes. In some cases, a pressure test of the lower unit will reveal a leak before visible signs appear.
How often should lower unit seals be replaced?
There is no fixed replacement interval. Seals should be inspected for leaks during every gear lube change (typically every 100 hours or annually). It is common practice to replace all seals whenever the gear case is opened for other service, such as bearing or gear replacement.
Does this kit include every seal needed for the job?
Yes, this is a complete kit containing all necessary seals for the lower unit gear case housing for the specified models. You should not need to purchase additional seals for a standard reseal job.
OEM vs. Aftermarket: What's the difference?
This listing is for an aftermarket replacement part, not an OEM (Original Equipment Manufacturer) component. It has been engineered to meet or exceed OEM specifications using comparable materials and is manufactured in an ISO 9002 certified facility. All parts are batch-inspected to ensure quality and consistency.
How fast is shipping and what does it cost?
We ship worldwide quickly, with typical transit times of 5–15 days for most regions. Standard shipping is free. Expedited shipping options, if available for your location, will be presented at checkout.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for unused parts in their original condition. See our full policy page or contact us for instructions.
Safety & Important Info
- Verify images and specifications against your original part before ordering. If anything differs—even if your model is listed as compatible—do not purchase.
- This is an aftermarket replacement part, 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 rigorously tested for real-world conditions.
- Fast Global Fulfillment — We offer free standard delivery to most regions, with parts typically arriving in 5–15 days.
- Manufacturer-Direct Value — By working directly with manufacturers, we provide fair pricing without compromising on materials or quality control.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
