Shop

Home

Parts

Owner Support
- Start Here
- Owner Support

Merchandise
- Shop All Merchandise
- Apparel
- Accessories
- Hats
- Home
- Toys
- Brand Collection

Workshop

Specials & Offers
- Promotions
- Featured Offers

Quick Order

Home
Quick Order

A-AM877740: Alternator, 12 Volt, 40 Amp | Shop.Deere.com

Home

>
Engine Auxiliaries
>
Alternators
>
A-AM877740: Alternator, 12 Volt, 40 Amp

Alternatives

A-AM877740: Alternator, 12 Volt, 40 Amp

Part Number: A-AM877740

Parts Tier: Alternatives

Generally, parts purchased from Shop.Deere.com are covered by the John Deere Parts Warranty, covering defects in material and workmanship, for a minimum period of 6 months from receipt. For complete warranty information, please contact your local authorized John Deere dealer.

Built to Keep You Running

Subscribe to Shop.Deere.com emails for first looks at our latest products and offers! Plus an exclusive 10% off select merchandise welcome offer.

Get Started

Free Shipping Terms & Conditions: FREE 3-5 Day Ground Shipping on all online orders placed at Shop.Deere.com between August 1, 2026, and August 15, 2026. Free Shipping applies to Standard Delivery on all orders sent to a single shipment address in the United States. Additional Shipping & Handling may apply for select items or shipments to more than one address. Merchandise is subject to availability. Offer is subject to restrictions and may change without notice. Void where prohibited.

Merchandise Sale Restrictions: Take 15% off John Deere merchandise from Saturday, August 1, 2026 (12:00AM CST) - Saturday, August 15, 2025 (11:59PM CST). Some exclusions apply. Battery operated ride ons, parts, PROService, and LEGO Technic Sets are not included. Offer only valid at shop.deere.com and not valid with any other promotional discount. No adjustments to prior purchases. Merchandise subject to availability. Returns and exchanges will be subject to discount taken at time of purchase. Offer subject to restrictions and change without notice. Void where prohibited.

Construction Season Savings Restrictions: Receive 15% off qualifying construction equipment parts purchased from participating U.S. construction and forestry dealers on Shop.Deere.com between 01 August 2026 and 15 October 2026. EXCLUSIONS APPLY: John Deere merchandise, home and workshop products, and licensed products are excluded from this discount. Discount applied to the qualifying parts total in cart before applicable taxes, delivery charges, and fees. Offer has no cash value and cannot be redeemed for cash. Offer cannot be combined with any other offer and may be discontinued or modified at any time without notice.

Excavator Lifecycle Advantage Program Restrictions: Receive 15% off qualifying REMAN excavator parts purchased from participating U.S. construction and forestry dealers on Shop.Deere.com between 01 August 2026 and 15 October 2026. EXCLUSIONS APPLY: John Deere merchandise, home and workshop products, and licensed products are excluded from this discount. Discount applied to the qualifying parts total in cart before applicable taxes, delivery charges, and fees. Offer has no cash value and cannot be redeemed for cash. Offer cannot be combined with any other offer and may be discontinued or modified at any time without notice.

Batteries Promo Restrictions: Receive 10% off total agreed upon purchase price before applicable taxes, shipping rates, and delivery charges on new StrongBox Original Equipment batteries, StrongBox Standard - Duty batteries, and select battery accessories purchased from a participating John Deere dealer in the U.S. or on Shop.Deere.com between August 1, 2026, and September 30, 2026. Offer cannot be combined with any other offer and may be discontinued or modified without notice at any time. Other restrictions may apply.

Grease Promo Restrictions: Receive 15% off select parts, TO BE APPLIED TO THE AGREED UPON PURCHASE PRICE BEFORE APPLICABLE TAXES, SHIPPING RATES AND DELIVERY CHARGES. Offer valid between August 1, 2026, and August 31, 2026, at participating dealers in the U.S. and Canada. Offer has no cash value and cannot be redeemed for cash. Dealer participation may vary. Other restrictions may apply. Offer cannot be combined with any other offer and may be discontinued or modified without notice at any time. SEE YOUR JOHN DEERE DEALER FOR DETAILS.

Tractor Parts-a-thon Offer Details: Offer valid on qualifying purchases made between August 1, 2026, and September 30,2026. Receive 15% off the agreed-upon purchase price of selected parts for 1, 2, 3, and 4 Series Compact Utility Tractors and equivalent older models, with discount applied to the total before applicable taxes, shipping rates, and delivery charges. Limit of $1,500 USD/CAD discount per machine. One customer may submit up to maximum discount for each qualifying machine in their fleet. Not applicable towards the purchase of fluids (oils, antifreeze, etc.), grease, attachments, labor, radios, universal hardware, and accessories. John Deere merchandise and licensed products are excluded. No cash value. Some restrictions apply. Offer valid at participating John Deere dealers in the US/CA and on Shop.Deere.com.

Perks Welcome Offer Details: 20% off John Deere and A&I Products parts, under $2,500 USD, excluding merchandise, which includes but is not limited to clothing, hats, licensed products, battery operated ride-on toys, Customer Service Advisor, collectible art, LEGO Technic Sets, and sales tax and shipping & handling charges. Offer valid on new qualifying purchases made between 1 May, 2025, and October 15, 2026, on Shop.Deere.com while quantities last. Not valid on purchases made at Factory Locations or on John Deere Store merchandise purchased from other retailers or using third party websites. Additional exclusions may apply. Offer cannot be combined with any other offer or discount, except available shipping offers. Free Shipping applies to Standard Delivery on orders of $50 or more sent to a single shipment address in the United States. Additional Shipping & Handling applies for select items or shipments on oversized items. No adjustments to prior purchases. Returns and exchanges will be subject to discount taken at time of purchase. Offer subject to restrictions and change without notice. Void where prohibited. Additional exclusions may apply.

Customer Service

Start A Return
FAQ
Contact Us
Payment Information
Shipping & Handling
Warranty & Return Policy
Privacy Policy
Terms & Conditions
Cookie Preferences

Account

Account
Track Order
Email Sign Up
Create Account & Join Us

Products

Equipment
Find a Dealer
Buy Equipment Online
Build Your Own

Our Sites

Deere.com
Operations Center

Follow Us

instagram icon
facebook icon
linkedin icon
x icon
youtube icon

Site Map
Privacy & Data
Cookie Statement
Terms of Use
Accessibility
Contact Us

Copyright © 2025 Deere & Company. All Rights Reserved.