Mercury MerCruiser — Driveshaft Locknut, TR / TRS / SSM — 41527T
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Mercury MerCruiser Driveshaft Locknut, TR / TRS / SSM – Part 41527T
This genuine OEM driveshaft retaining nut secures the upper driveshaft/bearing stack on select older MerCruiser sterndrive driveshaft-housing and gear assemblies, working together with the specified driveshaft washer and lockwasher. This part is currently No Longer Available (NLA) from Mercury.
Part Details
- Part number: 41527T
- Full service number: 11-41527T
- Brand: Mercury MerCruiser / Quicksilver
- Product type: Driveshaft retaining nut
- System: Sterndrive / driveshaft / gear housing
- Quantity required: 1 per applicable assembly
- Availability: No Longer Available (NLA)
Compatible Applications
- MerCruiser TR / TRS, 1977–1993 (serial 4794900 and up)
- MerCruiser II-TR, 1973–1976
- 255 TRS, 1973–1974
- 280 TRS, 1975–1976
- Alpha One SS, 1986–1989
- SSM II / III / IV / V, 1982–1995
Confirm your exact drive model, serial number, and driveshaft-housing diagram before ordering, since these older sterndrive assemblies came in multiple gear ratios and internal configurations.
When to Replace
Replace this nut if the threads or wrenching surfaces are damaged, corrosion is excessive, or it can no longer secure the driveshaft assembly correctly. Inspect the related locking hardware any time the driveshaft bearing stack is serviced.
Installation Notes
Applicable diagrams show 41527T installed together with driveshaft tab washer 62795, driveshaft lockwasher 62788, driveshaft tapered roller bearing 38356A1, and oil-slinger coupling assembly 62787A1/A2. Follow the correct MerCruiser service procedure and torque specification for your specific drive.
Technical FAQ
Is a replacement still available from Mercury? This part is currently listed as No Longer Available (NLA); confirm current stock before planning a full driveshaft rebuild.
How do I confirm fitment on an older drive? Match your drive model and serial number against the driveshaft-housing diagram, since several similar nuts were used across TR/TRS and SSM sterndrive families.
Parts Desk Insights
This locknut is best used when rebuilding the driveshaft bearing stack on older TR/TRS or SSM sterndrives. The most common mistake is ordering it without checking the rest of the stack, since the surrounding washers, lockwashers, and bearings are often discontinued too and worth confirming availability for at the same time. For fitment, always match the exact drive family and serial number range rather than assuming interchangeability between similar-looking nuts.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.