1988 GMC S15 Pickup Oil Type & Capacity
The 1988 GMC S15 Pickup oil type depends on the engine: the 2D Pickup Extra Cab, 2.5 E, 4WD, Automatic takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup Extra Cab, 2.5 E, 4WD, Standard takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup Extra Cab, 2.5 E, RWD, Automatic takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup Extra Cab, 2.5 E, RWD, Standard takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup Extra Cab, 2.8 R, 4WD, Automatic takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup Extra Cab, 2.8 R, 4WD, Standard takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup Extra Cab, 2.8 R, RWD, Automatic takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup Extra Cab, 2.8 R, RWD, Standard takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup Extra Cab, 4.3 Z, 4WD takes 5W-30 (5.0 quarts qt with filter); the 2D Pickup Extra Cab, 4.3 Z, RWD takes 5W-30 (5.0 quarts qt with filter); the 2D Pickup, 2.5 E, 4WD, Automatic takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup, 2.5 E, 4WD, Standard takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup, 2.5 E, RWD, Automatic takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup, 2.5 E, RWD, Standard takes 5W-30 (3.5 quarts qt with filter); the 2D Pickup, 2.8 R, 4WD, Automatic takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup, 2.8 R, 4WD, Standard takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup, 2.8 R, RWD, Automatic takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup, 2.8 R, RWD, Standard takes 5W-30 (4.5 quarts qt with filter); the 2D Pickup, 4.3 Z, 4WD takes 5W-30 (5.0 quarts qt with filter); the 2D Pickup, 4.3 Z, RWD takes 5W-30 (5.0 quarts qt with filter), per the factory service manual.
Factory-spec answer
It depends on the engine:
- 2D Pickup Extra Cab, 2.5 E, 4WD, Automatic: 5W-30, 3.5 quarts with filter
- 2D Pickup Extra Cab, 2.5 E, 4WD, Standard: 5W-30, 3.5 quarts with filter
- 2D Pickup Extra Cab, 2.5 E, RWD, Automatic: 5W-30, 3.5 quarts with filter
- 2D Pickup Extra Cab, 2.5 E, RWD, Standard: 5W-30, 3.5 quarts with filter
- 2D Pickup Extra Cab, 2.8 R, 4WD, Automatic: 5W-30, 4.5 quarts with filter
- 2D Pickup Extra Cab, 2.8 R, 4WD, Standard: 5W-30, 4.5 quarts with filter
- 2D Pickup Extra Cab, 2.8 R, RWD, Automatic: 5W-30, 4.5 quarts with filter
- 2D Pickup Extra Cab, 2.8 R, RWD, Standard: 5W-30, 4.5 quarts with filter
- 2D Pickup Extra Cab, 4.3 Z, 4WD: 5W-30, 5.0 quarts with filter
- 2D Pickup Extra Cab, 4.3 Z, RWD: 5W-30, 5.0 quarts with filter
- 2D Pickup, 2.5 E, 4WD, Automatic: 5W-30, 3.5 quarts with filter
- 2D Pickup, 2.5 E, 4WD, Standard: 5W-30, 3.5 quarts with filter
- 2D Pickup, 2.5 E, RWD, Automatic: 5W-30, 3.5 quarts with filter
- 2D Pickup, 2.5 E, RWD, Standard: 5W-30, 3.5 quarts with filter
- 2D Pickup, 2.8 R, 4WD, Automatic: 5W-30, 4.5 quarts with filter
- 2D Pickup, 2.8 R, 4WD, Standard: 5W-30, 4.5 quarts with filter
- 2D Pickup, 2.8 R, RWD, Automatic: 5W-30, 4.5 quarts with filter
- 2D Pickup, 2.8 R, RWD, Standard: 5W-30, 4.5 quarts with filter
- 2D Pickup, 4.3 Z, 4WD: 5W-30, 5.0 quarts with filter
- 2D Pickup, 4.3 Z, RWD: 5W-30, 5.0 quarts with filter
Oil capacity by engine
| Engine | Oil Type (viscosity) | Capacity w/ Filter | Capacity w/o Filter | Notes |
|---|---|---|---|---|
| 2D Pickup Extra Cab, 2.5 E, 4WD, Automatic — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup Extra Cab, 2.5 E, 4WD, Standard — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup Extra Cab, 2.5 E, RWD, Automatic — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup Extra Cab, 2.5 E, RWD, Standard — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup Extra Cab, 2.8 R, 4WD, Automatic — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup Extra Cab, 2.8 R, 4WD, Standard — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup Extra Cab, 2.8 R, RWD, Automatic — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup Extra Cab, 2.8 R, RWD, Standard — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup Extra Cab, 4.3 Z, 4WD — 4.3L Eng | SAE 5W-30 (Below 0Deg.F to 60Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup Extra Cab, 4.3 Z, RWD — 4.3L Eng | SAE 5W-30 (Below 0Deg.F to 60Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup, 2.5 E, 4WD, Automatic — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup, 2.5 E, 4WD, Standard — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup, 2.5 E, RWD, Automatic — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup, 2.5 E, RWD, Standard — 2.5L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 3.00 QTS. | — |
| 2D Pickup, 2.8 R, 4WD, Automatic — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup, 2.8 R, 4WD, Standard — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup, 2.8 R, RWD, Automatic — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup, 2.8 R, RWD, Standard — 2.8L Eng | SAE 5W-30 (Below 0Deg.F to above 100Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup, 4.3 Z, 4WD — 4.3L Eng | SAE 5W-30 (Below 0Deg.F to 60Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
| 2D Pickup, 4.3 Z, RWD — 4.3L Eng | SAE 5W-30 (Below 0Deg.F to 60Deg.F), 10W-30 (Above 0Deg.F to over 100Deg.F), SAE 30 (Above 40Deg.F to over 100Deg.F) | — | 4.00 QTS. | — |
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More factory specs & repair guides for your S15 Pickup
🛞 1988 GMC S15 Pickup Tire Size & Pressure →🌧️ 1988 GMC S15 Pickup Wiper Blade Sizes →💡 1988 GMC S15 Pickup Light Bulb Sizes →📖 1988 GMC S15 Pickup Factory Service Manual →All fluid capacities (transmission, coolant, brakes)Powered by factory manual data from our partner network AllOEMManuals.com.
Coolant capacity
11.5 quarts (10.88 L) — 56/44 mixture of Ethylene Glycol Base Antifreeze and water. GM Specification 1825-M.
Frequently asked questions
What type of oil does a 1988 GMC S15 Pickup take?
It depends on the engine: 2D Pickup Extra Cab, 2.5 E, 4WD, Automatic uses 5W-30; 2D Pickup Extra Cab, 2.5 E, 4WD, Standard uses 5W-30; 2D Pickup Extra Cab, 2.5 E, RWD, Automatic uses 5W-30; 2D Pickup Extra Cab, 2.5 E, RWD, Standard uses 5W-30; 2D Pickup Extra Cab, 2.8 R, 4WD, Automatic uses 5W-30; 2D Pickup Extra Cab, 2.8 R, 4WD, Standard uses 5W-30; 2D Pickup Extra Cab, 2.8 R, RWD, Automatic uses 5W-30; 2D Pickup Extra Cab, 2.8 R, RWD, Standard uses 5W-30; 2D Pickup Extra Cab, 4.3 Z, 4WD uses 5W-30; 2D Pickup Extra Cab, 4.3 Z, RWD uses 5W-30; 2D Pickup, 2.5 E, 4WD, Automatic uses 5W-30; 2D Pickup, 2.5 E, 4WD, Standard uses 5W-30; 2D Pickup, 2.5 E, RWD, Automatic uses 5W-30; 2D Pickup, 2.5 E, RWD, Standard uses 5W-30; 2D Pickup, 2.8 R, 4WD, Automatic uses 5W-30; 2D Pickup, 2.8 R, 4WD, Standard uses 5W-30; 2D Pickup, 2.8 R, RWD, Automatic uses 5W-30; 2D Pickup, 2.8 R, RWD, Standard uses 5W-30; 2D Pickup, 4.3 Z, 4WD uses 5W-30; 2D Pickup, 4.3 Z, RWD uses 5W-30.
What is the oil capacity of a 1988 GMC S15 Pickup?
Oil capacity depends on the engine: 2D Pickup Extra Cab, 2.5 E, 4WD, Automatic holds 3.5 quarts with filter; 2D Pickup Extra Cab, 2.5 E, 4WD, Standard holds 3.5 quarts with filter; 2D Pickup Extra Cab, 2.5 E, RWD, Automatic holds 3.5 quarts with filter; 2D Pickup Extra Cab, 2.5 E, RWD, Standard holds 3.5 quarts with filter; 2D Pickup Extra Cab, 2.8 R, 4WD, Automatic holds 4.5 quarts with filter; 2D Pickup Extra Cab, 2.8 R, 4WD, Standard holds 4.5 quarts with filter; 2D Pickup Extra Cab, 2.8 R, RWD, Automatic holds 4.5 quarts with filter; 2D Pickup Extra Cab, 2.8 R, RWD, Standard holds 4.5 quarts with filter; 2D Pickup Extra Cab, 4.3 Z, 4WD holds 5.0 quarts with filter; 2D Pickup Extra Cab, 4.3 Z, RWD holds 5.0 quarts with filter; 2D Pickup, 2.5 E, 4WD, Automatic holds 3.5 quarts with filter; 2D Pickup, 2.5 E, 4WD, Standard holds 3.5 quarts with filter; 2D Pickup, 2.5 E, RWD, Automatic holds 3.5 quarts with filter; 2D Pickup, 2.5 E, RWD, Standard holds 3.5 quarts with filter; 2D Pickup, 2.8 R, 4WD, Automatic holds 4.5 quarts with filter; 2D Pickup, 2.8 R, 4WD, Standard holds 4.5 quarts with filter; 2D Pickup, 2.8 R, RWD, Automatic holds 4.5 quarts with filter; 2D Pickup, 2.8 R, RWD, Standard holds 4.5 quarts with filter; 2D Pickup, 4.3 Z, 4WD holds 5.0 quarts with filter; 2D Pickup, 4.3 Z, RWD holds 5.0 quarts with filter.
How often should I change the oil in my 1988 GMC S15 Pickup?
Most 1988 GMC S15 Pickup owners follow a 5,000–7,500 mile interval with conventional oil, or up to 10,000 miles with full synthetic. Always check the oil life monitor if equipped, and consult your owner's manual — GMC recommends intervals based on driving conditions, not just mileage.
Can I use synthetic oil in my 1988 GMC S15 Pickup?
Yes. 5W-30 is widely available as a full synthetic, and synthetic is safe (often recommended) for the 1988 GMC S15 Pickup. What matters most is matching the factory viscosity and specification, then changing the oil and filter on schedule.