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Buick Somerset

Maintenance specs for 2 variants of the Buick Somerset — from 1985 to 1987.

19851987 Buick Somerset

2.5L I4 (Tech IV) · FWD

92 hp / 134 lb-ft

Engine Oil

Weight5W-30
Capacity4 qt
FilterPF51

Transmission

Type3-Speed Automatic (3T40)
FluidDexron III
Drain & fill6 qt
Full capacity10 qt

Coolant

TypeConventional (green)
Capacity9.7 qt
Shop coolant

Brake Fluid

TypeDOT 3
Shop DOT 3

Power Steering

TypeHydraulic
FluidGM Power Steering Fluid

Fuel

Tank13.6 gal
TypeRegular 87

Tires

Size185/80R13
Pressure (front)30 PSI
Pressure (rear)30 PSI
Shop 185/80R13 tires

Battery

Group size75
CCA525 A
Shop group 75 battery

Spark Plugs

Gap0.06 in
Shop spark plugs

Wiper Blades

Driver18"
Passenger18"
Shop wiper blades

Service Intervals

Oil change3,000 mi
Trans service30,000 mi
Coolant flush30,000 mi
Spark plugs30,000 mi
Timinggear (no scheduled replacement)
Air filter45,000 mi
Cabin filter22,500 mi
Drive belt45,000 mi

19851987 Buick Somerset

3.0L V6 (LN7) · FWD

125 hp / 160 lb-ft

Engine Oil

Weight5W-30
Capacity4 qt
FilterPF47

Transmission

Type3-Speed Automatic (3T40)
FluidDexron III
Drain & fill6 qt
Full capacity10 qt

Coolant

TypeConventional (green)
Capacity11 qt
Shop coolant

Brake Fluid

TypeDOT 3
Shop DOT 3

Power Steering

TypeHydraulic
FluidGM Power Steering Fluid

Fuel

Tank13.6 gal
TypeRegular 87

Tires

Size185/80R13
Pressure (front)30 PSI
Pressure (rear)30 PSI
Shop 185/80R13 tires

Battery

Group size75
CCA525 A
Shop group 75 battery

Spark Plugs

Gap0.06 in
Shop spark plugs

Wiper Blades

Driver18"
Passenger18"
Shop wiper blades

Service Intervals

Oil change3,000 mi
Trans service30,000 mi
Coolant flush30,000 mi
Spark plugs30,000 mi
Timingchain (no scheduled replacement)
Air filter45,000 mi
Cabin filter22,500 mi
Drive belt45,000 mi