1999 Chevrolet Silverado 1500 Wheel Offset

ET31

Quick specs

OEM offset: ET31
Wheel size: 7x16
Backspacing: 4.72 in
Bolt pattern: 6×139.7
Center bore: 78.1 mm
Tire size: 235/75R16 · 255/70R16 · 245/75R16 · 265/75R16

OEM configurations

Configuration	Rim	Offset	Backspacing	Tire	Bolt pattern	Center bore	Thread
4.3 · 4.3L, V6, Petrol	7x16	ET31	4.72 in	235/75R16	6x139.7	78.1 mm	M14 x 1.5
4.3 · 4.3L, V6, Petrol	7x16	ET31	4.72 in	255/70R16	6x139.7	78.1 mm	M14 x 1.5
4.3 4WD · 4.3L, V6, Petrol	7x16	ET31	4.72 in	245/75R16	6x139.7	78.1 mm	M14 x 1.5
4.3 4WD · 4.3L, V6, Petrol	7x16	ET31	4.72 in	265/75R16	6x139.7	78.1 mm	M14 x 1.5
4.8 · 4.8L, V8, Petrol	7x16	ET31	4.72 in	235/75R16	6x139.7	78.1 mm	M14 x 1.5
4.8 · 4.8L, V8, Petrol	7x16	ET31	4.72 in	255/70R16	6x139.7	78.1 mm	M14 x 1.5
4.8 4WD · 4.8L, V8, Petrol	7x16	ET31	4.72 in	245/75R16	6x139.7	78.1 mm	M14 x 1.5
4.8 4WD · 4.8L, V8, Petrol	7x16	ET31	4.72 in	265/75R16	6x139.7	78.1 mm	M14 x 1.5
5.3 · 5.3L, V8, Petrol	7x16	ET31	4.72 in	235/75R16	6x139.7	78.1 mm	M14 x 1.5
5.3 · 5.3L, V8, Petrol	7x16	ET31	4.72 in	255/70R16	6x139.7	78.1 mm	M14 x 1.5
5.3 4WD · 5.3L, V8, Petrol	7x16	ET31	4.72 in	245/75R16	6x139.7	78.1 mm	M14 x 1.5
5.3 4WD · 5.3L, V8, Petrol	7x16	ET31	4.72 in	265/75R16	6x139.7	78.1 mm	M14 x 1.5

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See how a different width or offset sits versus an OEM configuration for this year.

OEM baseline

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Wheels and hardware for this vehicle

Lug hardware

Wheel locks

Real-World 1999 Chevrolet Silverado 1500 Wheel Setups

Observed aftermarket setups from documented Modified1 builds. These are individual build records — not OEM specifications and not clearance guarantees for every vehicle.

Common custom wheel sizes

Among builds in our database for this model year:

15-inch — 1 documented build
20-inch — 1 documented build

2 documented builds.

15×7.5 ET-12

Documented on a 1999 Chevrolet Silverado 1500 build — observed custom fitment, not a universal fit guarantee.

Tires: 31/10.5R15

Suspension: Suspension Lift 4"
Spacers: 1.5"
Wheel offset: ET-12
Effective position: approximately ET-50.1 (calculated)

Compared with OEM

Compared with the 16×7 ET31 OEM configuration. Calculated geometry only — not fit confirmation.

Outer edge 87.5 mm farther toward fender (more outward poke)
Inner edge 74.8 mm farther from suspension (more inner clearance)
Width +0.5" vs OEM
Diameter -1" vs OEM

View full build on Modified1

1999 Chevrolet Silverado 1500 custom wheel setup

20×9 ET18

Documented on a 1999 Chevrolet Silverado 1500 build — observed custom fitment, not a universal fit guarantee.

Tires: 295/55R20

Suspension: Suspension Lift 3.5"

Compared with OEM

Compared with the 16×7 ET31 OEM configuration. Calculated geometry only — not fit confirmation.

Outer edge 38.4 mm farther toward fender (more outward poke)
Inner edge 12.4 mm closer to suspension (less inner clearance)
Width +2" vs OEM
Diameter +4" vs OEM

View full build on Modified1

More specs for the 1999 Chevrolet Silverado 1500

OEM offsets are catalog configurations, not an aftermarket “safe ET range.” Matching offset alone does not confirm clearance. Documented custom builds are observed setups only.