The GMC Sonoma is the GMC version of the small pickup Chevrolet sold as the S10. It was the S15 until GMC renamed it Sonoma for 1991, and the catalogue titles carry S10, S15 and Sonoma together — so a listing found here is the same part as the Chevrolet-badged one, correctly coded. The Jimmy SUV used the same S10/S15 platform but is a different vehicle and is listed separately.
These listings run from 1990 to 2004 and cover four displacements. Most are the 4.3 Vortec V6. The 2.2 four-cylinder is the next largest group, and the 2.5 four and the 2.8 V6 appear only in the earliest years.
GMC Sonoma used engines — options by year
| Years listed |
Engine |
VIN code (8th digit) |
Notes |
| 1990–1993 |
2.8L V6 (6-173) |
R |
Carried over from the first generation |
| 1991–1993 |
2.5L I4 (4-151) |
A, E |
The Iron Duke four |
| 1994–2003 |
2.2L I4 (4-134) |
4, 5, H |
The economy four |
| 1990–1995 |
4.3L V6 (6-262) |
Z, W |
Z is throttle body, W is CPI — different fuel systems |
| 1996–2004 |
4.3L V6 (6-262) |
W, X |
Vortec head revision from 1996 |
How to pick the right one
The eighth character of the VIN does the work here, because it separates engines that the year alone cannot. On the 4.3 it is the whole decision: VIN Z is throttle body injected and VIN W is central port injection, and one does not stand in for the other without changing the intake and fuel hardware. Two further splits run through these listings. For 1995 the 4.3 appears twice, once with side mounted and once with top mounted spark plug wires on the distributor, which you can check against your own engine before ordering. For 1998 the 4.3 is split by build date option ZN4. On the earlier 4.3, four-wheel-drive and two-wheel-drive versions are listed apart because the oil pan and dipstick arrangement differ. Because the Chevrolet and GMC trucks are the same vehicle, widen your search to the S10 listings if the exact year and code you need is not here.
What usually goes wrong on these engines
On the 4.3 the fault behind most replacements is not the block. It is the central port injection unit — the spider — whose poppet nozzles leak and flood the intake, and the intake manifold gasket, which weeps coolant into the valley. Both can be put right without replacing the engine, so work out which one you have before you buy. The 2.2 is tough but unforgiving of a low oil level; a stretched timing chain or a head gasket is usually what finishes one. The 2.8 is the weakest of the four and parts availability for it is thinning, which is why so few appear here.
What ships with every unit
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Condition as listed — each product page states the condition and the mileage options, which are priced separately.
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VIN matched fitment — send us your VIN and we confirm the engine code against your vehicle before the order ships.
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Written warranty — 3 months on units up to 2000, 6 months on 2001 and newer, extendable to 3 years, parts only. Labour is not included unless you buy a separate agreement.
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Free freight anywhere in the lower 48, shipped on a pallet to a commercial address or a terminal.
Related reading: GM 4.3L Vortec V6 engine guide, Chevrolet S10 used engines, S10 and Sonoma used transmissions, all engine guides.
GMC Sonoma used engines — frequently asked questions
Which engines did the GMC Sonoma use?
These listings cover the 2.8L V6, the 2.5L four, the 2.2L four and the 4.3L Vortec V6, across 1990 to 2004. The 4.3 is much the most common and the 2.8 the least common.
Is a GMC Sonoma engine the same as a Chevrolet S10 engine?
Yes. The Sonoma, the S15 and the S10 are the same truck under different badges, and the catalogue titles name all three together. A correctly coded engine from either badge is the same part, so it is worth searching both.
Was the GMC Sonoma called something else?
It was the GMC S15 before 1991 and the GMC Sonoma from 1991 onward. Both names appear in these listings alongside S10.
Will a GMC Jimmy engine fit my Sonoma?
The Jimmy shares the S10/S15 platform and the same engine families, but it is a different vehicle and is listed separately from the pickup. Match on the VIN character rather than on the platform name.
What comes with a used GMC Sonoma engine?
Each listing states its condition and its mileage options. Fitment is matched to your VIN before the order goes out, every unit carries a written warranty of 3 months up to 2000 and 6 months on 2001 and newer, extendable to 3 years, parts only, and freight is free anywhere in the lower 48.
