Isuzu H series (USA / CAN)

Automatic transmission fluid capacity & service interval

Isuzu H series (USA / CAN) automatic transmission fluid capacity is 24,6 liters. Service intervals include checking at 7500 miles or 3 months, and changing at 12000 miles or 6 months, 25000 miles or 12 months, 75000 miles or 36 months, and 150000 miles or 48 months. The data covers 8 configurations.

The configuration chart below lists fill volumes and service intervals for each engine and trim variant.

TypeSpecifications
H series (2007-2008)
  • Use: Preferred
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 150000 miles/ 48 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1
H series (2007-2008)
  • Use: Alternative (acceptable)
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 25000 miles/ 12 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1
H series (2007-2008)
  • Use: Alternative, severe
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 12000 miles/ 6 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1
H series (2007-2008)
  • Use: Preferred, severe
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 75000 miles/ 36 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1
H series (2003-2006)
  • Use: Preferred
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 150000 miles/ 48 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1
H series (2003-2006)
  • Use: Alternative (acceptable)
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 25000 miles/ 12 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1
H series (2003-2006)
  • Use: Alternative, severe
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 12000 miles/ 6 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1
H series (2003-2006)
  • Use: Preferred, severe
  • Capacity 24,6 liter
  • Check 7500 miles/ 3 months
  • Change 75000 miles/ 36 months
  • Code: Allison 3000RDS, 3500RDS (EVS) 6/1

Additional Notes

  • The Isuzu H series (USA / CAN) automatic transmission carries a fluid capacity of 24.6 liters across all listed configurations from 2003-2008, a volume consistent with a full overhaul or dry-fill figure rather than a routine service top-up.
  • The check interval is set at 7,500 miles or 3 months for every configuration across both the 2003-2006 and 2007-2008 model year groups, regardless of fluid type or use condition.
  • Under the preferred fluid in normal use conditions, the change interval reaches 150,000 miles or 48 months, one of the longest drain intervals specified across all configurations in the 2003-2008 range.
  • When the alternative (acceptable) fluid is used under normal conditions, the change interval drops sharply to 25,000 miles or 12 months, reflecting a significantly more frequent service requirement compared to the preferred fluid under the same conditions.
  • Severe use conditions applied to the preferred fluid result in a change interval of 75,000 miles or 36 months, which is half the mileage and three-quarters of the time allowance of the preferred fluid under normal conditions.
  • The most frequent change interval across all configurations is 12,000 miles or 6 months, assigned to the alternative fluid under severe use conditions, applying equally to both the 2003-2006 and 2007-2008 model year groups.
  • The fluid capacity, check interval, and change intervals are identical between the 2003-2006 and 2007-2008 model year groups across all four use condition pairings, indicating no specification revision occurred between those two production periods.

Other Systems