Chevy Colorado DIY Maintenance Guide (2015–2024)

The second-generation Chevy Colorado (2015–present) is a midsize truck that punches above its weight in capability. With two gas engines (2.5L I4 and 3.6L V6) and an available diesel (2.8L Duramax), it covers a wide range of use cases — and all of them are DIY-friendly with the right information. Here's what you need to know.

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Oil Changes: Specs for Every Engine

2.5L I4 (Base Gas Engine)

Oil spec: 5W-30 full synthetic (dexos1 Gen 2 required — GM's specification, not optional) Capacity: 5 quarts with filter Interval: Up to 7,500 miles with the Oil Life Monitor, but 5,000–6,000 is better for higher-mileage trucks

The 2.5L is a simple, reliable engine. The drain plug is accessible and the filter is a cartridge-style setup on top of the engine — no wrench required, just a 32mm socket.

3.6L V6

Oil spec: 0W-20 dexos1 full synthetic Capacity: 6 quarts with filter Interval: 7,500 miles max, 5,000 for trucks that tow or idle a lot

The V6 uses an oil filter that requires a cartridge cap wrench (32mm on most applications). The filter is on the front of the engine, accessible from the top. Spin the cap off, pull the old element out, install a new one, reinstall the cap.

2.8L Duramax Diesel

Oil spec: 0W-20 full synthetic diesel-rated oil (dexos D) Capacity: 6.4 quarts with filter Interval: 10,000 miles with normal use, 7,500 if you're towing frequently

The Duramax diesel in the Colorado is a different animal — it rewards consistent maintenance and punishes neglect. Don't stretch the oil change intervals on this engine.

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Spark Plugs: 2.5L and 3.6L Only

The diesel Colorado doesn't have spark plugs (it has glow plugs — a different service item). The gas engines do.

2.5L I4

Four plugs, relatively easy access. Recommended plug: ACDelco Iridium (part number 41-162 or equivalent). Interval: 97,500 miles on the factory iridium plugs, though checking condition at 60,000 is wise.

3.6L V6

Six plugs, three on each bank. The rear bank (firewall side) is harder to reach and typically requires removing the intake plenum or working through a gap with an extension. Recommended plug: ACDelco 41-162 iridium. Same interval as the I4. This job is manageable for an experienced DIYer but factor in extra time for the rear bank.

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4WD Service: Transfer Case and Front Differential

Transfer Case Fluid

Fluid spec: Auto-Trak II transfer case fluid (GM P/N 89021807 or equivalent) Service interval: 45,000 miles or every 3 years, whichever comes first Capacity: About 1.6 quarts

The transfer case on the 4WD Colorado has a drain plug and fill plug. Warm the fluid by driving first — warm fluid drains more completely. Drain, reinstall the drain plug, fill to the bottom of the fill hole, reinstall the fill plug. Don't over-fill.

Front Differential

Fluid spec: 80W-90 conventional gear oil (check your owner's manual — some applications use 75W-90 synthetic) Service interval: 45,000 miles, or after any water crossing

This is a simple drain-and-fill. The front differential on the Colorado is on the driver side of the front axle. The fill plug is on the side; the drain plug is on the bottom.

Rear Differential

Fluid spec: 75W-90 synthetic gear oil Service interval: 45,000 miles under normal use; more frequently if you tow or see water crossings

Same procedure as the front diff — drain and fill. Inspect the fill plug for metal shavings while you have it out. A light metallic paste on the drain plug magnet is normal wear. Chunks or heavy contamination indicate bearing or gear issues.

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AFM Lifter Failure: The Colorado's Biggest DIY Concern

The 3.6L V6 uses Active Fuel Management (AFM) — GM's cylinder deactivation system that shuts off three cylinders under light load to improve fuel economy. It's the same system used in the V8 engines that has caused widespread lifter failures across GM's truck lineup.

What Happens

AFM uses special "collapsing" lifters that can hydraulically deactivate. Over time, these lifters can fail — the lifter collapses when it shouldn't, causing a cylinder to stop firing and generating a loud tapping or lifter noise. In severe cases, lifter debris circulates through the oil and damages the camshaft.

Symptoms

• Loud ticking or tapping noise, especially at idle
• Misfires on specific cylinders
• Oil consumption higher than normal
• Check engine light with misfire codes (P0300s) or cylinder deactivation codes

The DIY Options

Range AFM/DoD Disabler — a plug-in device (or tuner) that disables the AFM system. This stops the cylinders from deactivating and eliminates the stress on the AFM lifters. It won't fix already-damaged lifters but prevents the failure in healthy engines. This is a popular preventative mod on Colorado V6 and Silverado/Sierra V8 trucks alike.

Full AFM Delete — replace the AFM lifters with standard LS-pattern lifters and disable AFM in the ECU. This is a significant engine-out job, not for beginners, but it permanently solves the problem.

Regular oil changes — the biggest prevention factor. AFM lifters fail faster when oil is dirty or low. Run full synthetic dexos1, change on schedule, and don't let the oil level drop.

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Timing Chain: Know the Signs

The 3.6L V6 has been associated with timing chain wear, particularly at higher mileage. The symptoms are subtle at first:

• Rattle or slapping noise on cold start that disappears as the engine warms (chain slack before oil pressure builds)
• Check engine light with cam timing or cam position codes
• Rough running or poor performance

The timing chain is a big job — not a beginner repair. But catching it early with regular oil changes and addressing it when symptoms first appear is far better than letting a failed chain trash the engine.

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Additional Maintenance Items

Cabin Air Filter

Behind the glove box. No tools — pinch the tabs, open the box, slide out the old filter, slide in the new one. Change every 15,000–20,000 miles.

Engine Air Filter

In the airbox on the driver's side. Two clamps and a hose clamp. Five-minute job. Check every 15,000 miles, replace when visibly dirty.

Coolant Flush

The 2.5L and 3.6L use Dex-Cool (orange/red extended-life coolant). Do not mix Dex-Cool with green conventional coolant. Full flush interval: every 5 years or 150,000 miles per GM's spec, but 60,000–100,000 is more practical for a maintained truck.

Fuel Filter (Diesel)

The 2.8L Duramax has an in-tank fuel filter and a fuel filter/water separator on the engine. The water separator should be drained at every oil change — there's a drain screw at the bottom. Replace the filter element every 22,500 miles.

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Wrapping Up

The Colorado is one of the more DIY-friendly midsize trucks on the market. The I4 and V6 gas engines are accessible and straightforward. The diesel is manageable for experienced mechanics. The one thing to stay ahead of on the V6 is the AFM system — proactive oil changes and a disabler tune are the best insurance.

Get full Colorado service procedures with torque specs, fluid part numbers, and step-by-step instructions on an OwnerDrop Starter plan.