Which Colorado have you got?
RC, 2008 to 2011. The earlier ute.
RG, from June 2012. A 2.8-litre Duramax turbo-diesel with a five-speed manual or six-speed automatic.
RG Series II, from October 2013. A stronger 2.8-litre, with a six-speed manual or six-speed automatic.
With Holden gone since the end of 2020, the mechanic needs your exact year, cab and gearbox to find the right parts and bulletins.
Common Holden Colorado problems
These come from recalls, GM bulletins and owner reports, so use them as a checklist.
Oil use. On 2014 to 2016 utes, oil may drop before the next service. GM's update changed the oil to a 5W-40 diesel grade and replaced the oil cap. A dipstick change on 2015 to 2016 utes can also make it look worse than it is, and a revised dipstick followed.
Airbag light. On 2012 to 2016 utes, wires in the front door harness can break where the door flexes, setting codes B0085 or B0086. GM extended cover to 6 years or 120,000 km, which has now run out for most. It's a known repair, so don't leave the light on. An airbag light can mean the airbag won't work.
Coolant loss. The rear Welch plug on the cylinder head (a small casting plug) can leak. Watch the level, because coolant loss can bring on overheating. On an older ute, CarsGuide says to pressure-test the system and check the overflow tank for a small crack.
Fifth gear on 2014 manuals. Under heavy load at high speed, the fifth gear thrust washer can fracture, knocking it out of gear and locking the rear wheels. If a manual jumps out of fifth, don't tow with it until it's checked.
4WD selection. CarsGuide says a Colorado that won't hold 4WD, or keeps shifting into it, can have a worn rotary dial or control fault.
RC utes. Turbo lag and power loss can come from an EGR valve stuck open. The diesel fuel cooler is mounted low, so it can cop damage off road.
A squeak from the suspension. Often a worn shock absorber bush. Revised pins and bushes are available.
Recalls to check
Alternator cable, built 4 September 2013 to 21 January 2015. The cable could touch a steel bracket at the battery tray, short out and start a fire.
Seatbelts. Space Cabs built 15 September 2011 to 16 June 2015 could be missing a rear seatbelt anchor bolt, and utes built 12 January to 18 March 2015 could have a loose front retractor bolt.
These matter on a used ute, because the last owner may not have had them done.
Holden Colorado service schedule
carsales lists the 2018 Colorado at every 9 months or 12,000 km. Check your book, as other years may differ.
The 9-month limit is the one that catches people out, especially on a second vehicle. A tradie's ute or a tow vehicle can also need more attention than the book's minimum, so tell the mechanic about loads, dust and water crossings.
What a Colorado service should cover
- Engine oil and filter, in the grade GM's update specifies for your year.
- Fuel filter and air filter, as the book lists them.
- Coolant level and any sign of leaks at the back of the head.
- Transfer case and diff oils on a 4WD, when due.
- Front and rear brakes, tyres, ball joints and suspension bushes.
- A scan for stored codes, including the airbag system.
Where we'd start with a Colorado
Check the oil every couple of weeks and write down what you add, because a record helps the mechanic. Run the VIN for recalls. Then take the ute to a local mechanic who sees a lot of diesels, and ask for the estimate to name the oil grade and each item done. If you tow, say so before they start.