How much transmission fluid does a 2018 GMC Terrain take?

10 quarts as a total fill for the 9T45 transmission (9 to 10 quarts across this year's engines). A drain-and-refill without removing the pan replaces roughly a third to half of that, so refill to the level check point rather than pouring in the whole figure.

What transmission fluid does a 2018 GMC Terrain use?

The source lists only a catalog code for this year, not the OEM specification, so use the fluid named in your owner's manual or on the dipstick.

What brake fluid does a 2018 GMC Terrain take?

Check the brake fluid reservoir cap - it states the DOT grade. DOT 3 and DOT 4 can be mixed; DOT 5 silicone fluid cannot.

2018 GMC Terrain transmission fluid capacity and fluid specs

GarageDex's fluid data shows the 2018 GMC Terrain (1.5L 4-cyl) uses the 9T45 automatic transmission, which holds 10 quarts of fluid as a total fill. Other engines on this year hold 9 to 10 quarts - see the table.

Shop transmission fluid Match the specification on the bottle to your manual

Key takeaways

Transmission: 9T45 automatic transmission, 10 qt total fill.
Total fill is the whole system; a drain-and-refill takes a third to half.
Brake fluid grade: read it off the reservoir cap.
Fluid specification is not named by the source - use the owner's manual.

2018 GMC Terrain fluids by engine
Engine	Transmission	Total fill	Fluid spec	Brake fluid	Gear oil
1.5L 4-cyl	9T45 automatic	10 qt	per owner's manual	see reservoir cap	rear 0.85 qt transfer case 75W-90 0.85 qt
1.6L 4-cyl	6T45 automatic	9 qt	per owner's manual	see reservoir cap	rear 0.85 qt transfer case 75W-90 0.85 qt
2.0L 4-cyl	9T50 automatic	10 qt	per owner's manual	see reservoir cap	rear 0.85 qt transfer case 75W-90 0.85 qt

Fluids for the 2018 GMC Terrain

Buy fluid that states the specification your manual names. Multi-vehicle fluids list the specs they meet on the back label - if yours is not listed, it is the wrong bottle.

Transmission fluidYou need about 10 quarts for a full fillShop fluid DOT 3 or DOT 4 brake fluidA quart covers a full flushShop brake fluid Fluid transfer pumpMost modern transmissions have no dipstick tube - you fill from belowShop pumps

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Other 2018 GMC Terrain specs

All specs Engine oil Coolant capacity Maintenance schedule

Other Terrain years

2017 2016 2015 2014 2013 2012 2011 2010

Source: World's Best Oil (AMSOIL dealer cross-reference). Capacities are total system fills; a drain-and-refill takes less. Where no fluid specification is shown, the source lists only a catalog code, so use the specification printed in your owner's manual - the wrong transmission fluid damages a transmission.