John Deere 8120 Battery Size (Group 31) + Replacement Guide

Quick answer:

The John Deere 8120 battery size is listed as Group 31, 12 V, 13 × 6.81 × 9.44 in.

Battery sizeGroup 31
Voltage12 V
Case size13 × 6.81 × 9.44 in

John Deere 8120 Battery Specs

Battery size / group Group 31
Battery voltage 12 V
Battery dimensions 13 × 6.81 × 9.44 in

Battery Spec Comparisons Chart

Voltage comparison

This model

12 V

Average

11.66 V

Low

6 V

High

24 V

Case length comparison

This model

13 in

Average

11.13 in

Low

7.75 in

High

13 in

John Deere 8120 Battery FAQ

Replacement battery recommendation The best replacement battery for a John Deere 8120 tractor is the John Deere StrongBox battery, which is designed to meet the demanding specifications of John Deere equipment. It is known for its durability and reliability in harsh conditions
Battery voltage The John Deere 8120 tractor uses a 12-volt electrical system with two batteries rated at 12 volts each
Battery group size The official battery group size for the John Deere 8120 tractor is Group 31. This size is commonly used for many John Deere tractors and provides the necessary power for reliable starting
Battery CCA The recommended official John Deere 8120 tractor battery has a Cold Cranking Amps (CCA) rating of 925
Battery location The battery on the John Deere 8120 tractor is located underneath the right access step. You may need to open the flap and possibly remove the access step to reach it
Battery replacement steps To replace the battery on a John Deere 8120 tractor, locate the battery underneath the right access step, open the flap, and if necessary, remove the access step by taking out the attaching screws. Then, follow the proper disconnection and connection procedures for the battery cables to ensure safety
Bad battery symptoms Common symptoms of a failing battery in a John Deere 8120 tractor include hard starting or no response when trying to start, clicking sounds, and rapid battery drain. Additionally, corrosion on battery terminals can prevent proper electrical flow, leading to starting issues
Official information note

Mistakes do happen. Please check official deere.com website for official information.