CadillacCT62018Overview/cadillac/ct6/2018/base/

2018 Cadillac CT6

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2018 CT6.

Body PASSENGER CARTransmission Automatic (S8)

The 2018 Cadillac CT6 is a full‑size passenger car whose engine calls for 6.0 qt of 5W‑30 oil and is mated to an eight‑speed automatic transmission, delivering an EPA‑rated 22/30/25 mpg city/highway/combined. Owner‑reported data show just ten total complaints for the model year, with the power‑train category leading the issues and two recalls issued, placing the 2018 at the low end of the 20162020 complaint range where 2017 peaked at 26 complaints. This low complaint count suggests the 2018 CT6 is comparatively more reliable within its generation.

Model year20202019201820172016

Quick specs

Fluid capacities, tune-up values and fuel economy at a glance.

Engine oil capacity6.0 qtOEM · verified
Engine oil type5W-30OEM · verified
Lug nut torque110 ft-lbsOEM · verified
EPA fuel economy22/30/25 mpgEPA · verified

Fitment & sizes

Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.

From the factory this vehicle uses a BCI 49 · 850 CCA battery, OE oil filter 12693541. Each part links to every other vehicle that shares it, so a part you already stock may fit more of your fleet than you'd expect.

Battery groupBCI 49 · 850 CCAOEM · verified

OE service part numbers OEM · verified

Engine oil filter12693541 alt 25206377
Engine air filter23441383 alt 23450879
Spark plug12681659 alt 12646780
Battery88864539
Front wiper blades84574893 alt 84574892
Serpentine belt12678130 alt 12654891
Thermostat12630780 alt 12678784
Cabin air filter13508023 alt 23195727

Full specifications

Engine, drivetrain, dimensions and economy.

Engine & drivetrain NHTSA vPIC

TransmissionAutomatic (S8)

Dimensions & weight NHTSA vPIC

Overall length203.9 in
Overall width74 in
Overall height57.9 in
Wheelbase122 in
Curb weight3646 lb
Track (front / rear)64.2 / 65 in
Weight distribution (front / rear)51/49

Ratings & economy EPA / vPIC

EPA city / highway / combined22 / 30 / 25 mpg
DrivetrainRear-Wheel Drive
Passenger volume110 cu ft
Cargo volume15 cu ft
Recommended fuelPremium Gasoline

Performance & power Independent road tests

0–60 mph, quarter-mile, horsepower and torque from independent road tests.

Independent road tests for the CT6 of this era, listed by trim and engine — this page spans more than one engine, so no single horsepower figure is shown.

4.7–7.5 sec0–60 mph (tested)quickest 4.70 sec — 2017 Platinum 3.0TT Sedan
YearTrim / engine0–60¼ mileHPDrivetrain
2017Platinum 3.0TT Sedan 3.0L Twin-Turbo V64.70 sec13.20 sec404 hpAWD
2017Platinum 3.0TT Sedan 3.0L Twin-Turbo V65.10 sec13.60 sec404 hpAWD
20172.0E Plug-In Hybrid Sedan 2.0L Turbo I-4 + Elec 18.4-kWh5.20 sec13.80 sec335 hpRWD
2017Luxury 2.0T Sedan 2.0L Turbo I-46.40 sec14.70 sec265 hpRWD
2019Premium Luxury Sedan 2.0L Turbo I-47.50 sec15.70 sec237 hpRWD
2016Platinum 3.0TT Sedan 3.0L Twin-Turbo V65.00 sec13.50 sec404 hpAWD
2016Platinum 3.0TT Sedan 3.0L Twin-Turbo V65.00 sec13.40 sec404 hpAWD
2016Platinum 3.0TT Sedan 3.0L Twin-Turbo V65.40 sec13.70 sec404 hpAWD

Service quick specs OEM factory data

Capacities, torques and tune-up values from the factory service manual.

This engine holds 6.0 qt of 5W-30 engine oil, DOT 4 · DOT 3 brake fluid. Torque lug nuts to 110 ft-lbs. The firing order is 1-2-3-4-5-6. Note the cylinder-head bolts finish on a torque angle (torque-to-yield) — they stretch permanently and should be replaced, not reused, during any head service.

Lubricants & capacities

Automatic Transmission FluidUse Dexron HP
Automatic Transmission Fluid Capacity6.4-7.4
Brake FluidDOT 4 · DOT 3
Clutch FluidDOT 3
Engine Oil5W-30
Engine Oil Capacity6.0 qt
Engine Oil5W-30
Engine Oil Capacity6.0 qt

Engine torques

Crankshaft Position (CKP) Sensor Bolt(s)7.4 ft-lbs
Camshaft Position (CMP) Sensor Bolt(s)7.4 ft-lbs
Crankshaft Position (CKP) Sensor Bolt(s)7.4 ft-lbs
Camshaft Position (CMP) Sensor Bolt(s)7.4 ft-lbs
Crankshaft Position (CKP) Sensor Bolt(s)7.4 ft-lbs
Camshaft Position (CMP) Sensor Bolt(s)7.4 ft-lbs
Camshaft Bearing/Carrier Cap Bolts or Studs89.0 inch lbs. ft-lbs
Camshaft Bearing/Carrier Cap Bolts or Studs89.0 inch lbs. ft-lbs

Chassis torques

Lug Nuts110 ft-lbs

Ignition

Cylinder Firing Order1-3-4-2
Cylinder Firing Order1-2-3-4-5-6
Spark Plug ManufacturerAC Delco
Spark Plug Gap.037 - .043 in
Spark Plug Torque15 ft-lbs
Spark Plug ManufacturerAC Delco
Spark Plug Gap.035 in
Spark Plug Torque13 ft-lbs

Battery & A/C

Oil Type46
Oil Capacity4.10 oz
Standard BCI Group Number49
Standard BCI Cranking Performance850 cca

Service checks

Key ON Engine OFF (KOEO)50.0-94.0
Fuel Pump Pressure Minimum50.0 psi
Fuel Pump Pressure Maximum100.0 psi
Key ON Engine OFF (KOEO)50.0-100.0
Engine Compression100

Brakes

Brake Caliper Bolt to Carrier Torque30
Brake Caliper Carrier to Hub Bolt TorqueFront: 118; Rear: 92
Vented Rotor Minimum Thickness for ReplacementFront: 1.063; Rear: .827
Vented Rotor Minimum Thickness after RefinishFront: 1.102; Rear: .866
Variation from Parallelism Thickness Variation.001
Maximum Rotor Runout.002

Multi-step torque procedures OEM · verified

Front Wheel Hub — tightening sequence 1 stages
1111.0 ft. lbs., Step 2: Back off 45.0 degrees, Step 3: 199.0111 ft. lbs
Rear Wheel Hub — tightening sequence 1 stages
1111.0 ft. lbs., Step 2: Back off 45.0 degrees, Step 3: 199.0111 ft. lbs
Camshaft Sprocket and/or Gear Bolt(s) — tightening sequence 1 stages
122.0 ft. lbs., Step 2: 10022 ft. lbs
Camshaft Sprocket and/or Gear Bolt(s) — tightening sequence 1 stages
114.0 ft. lbs., Step 2: 4514 ft. lbs
Connecting Rod (Large End) Bearings — tightening sequence 4 stages
122.0 ft. lbs.22 ft. lbs
2Back off 360 degrees360 degrees
318.0 ft. lbs.18 ft. lbs
4110.0
Connecting Rod (Large End) Bearings — tightening sequence 2 stages
118.0 ft. lbs.18 ft. lbs
2110.0
Connecting Rod (Large End) Bearings — tightening sequence 4 stages
122.0 ft. lbs.22 ft. lbs
2Back off 360 degrees360 degrees
318.0 ft. lbs.18 ft. lbs
4110.0
Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages
1111.0 ft. lbs., Step 2: 140 degrees Use new bolts.111 ft. lbs
Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages
174.0 ft. lbs., Step 2: 150 degrees.74 ft. lbs
Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages
174.0 ft. lbs., Step 2: 15074 ft. lbs
Cylinder Head — tightening sequence 2 stages

Prep Do not re-use old bolts. Do not allow oil to contaminate cylinder head surface or head bolt bosses.

122.0 ft. lbs.22 ft. lbs
2190 degrees190 degrees
Cylinder Head — tightening sequence 2 stages

Prep Do not re-use old bolts. Do not allow oil to contaminate cylinder head surface or head bolt bosses. · M11 Bolts

144.0 ft. lbs.44 ft. lbs
2150 degrees; M8 Bolts150 degrees
111.0 ft. lbs.11 ft. lbs
275 degrees75 degrees
Intake Manifold to Engine Bolts — tightening sequence 2 stages
18.8 ft. lbs.8.8 ft. lbs
28.8
Exhaust Manifold to Cylinder Head Bolts — tightening sequence 3 stages
115 ft. lbs.15 ft. lbs
215 ft. lbs.15 ft. lbs
315
Intake Manifold to Engine Bolts — tightening sequence 2 stages
1Upper Bolts8.8 ft. lbs
218
Main Bearings — tightening sequence 2 stages

Prep Inner bolts

115.0 ft. lbs.15 ft. lbs
280 degrees; Outer bolts80 degrees
111.0 ft. lbs.11 ft. lbs
2110.0 degrees; Side bolts110 degrees
122.0 ft. lbs.22 ft. lbs
260.0 degrees60 degrees
Main Bearings — tightening sequence 2 stages

Prep Lower crankcase crankshaft bolts

115.0 ft. lbs.15 ft. lbs
2140 degrees; Lower crankcase perimeter bolts140 degrees
118.0 ft. lbs.18 ft. lbs
Main Bearings — tightening sequence 2 stages

Prep Inner bolts

115.0 ft. lbs.15 ft. lbs
280 degrees; Outer bolts80 degrees
111.0 ft. lbs.11 ft. lbs
2110.0 degrees; Side bolts110 degrees
122.0 ft. lbs.22 ft. lbs
260.0 degrees60 degrees
Oil Pan to Block Bolts — tightening sequence 1 stages
115.0 ft. lbs., Step 2: 14015 ft. lbs
Engine Valve Cover Bolts — tightening sequence 1 stages
17.4 ft. lbs., Step 2: 7.47.4 ft. lbs

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the engine oil and filter every 7,500 mi; spark plugs every 60,000 mi; coolant at 150,000 mi. The big-interval services (at 150,000 mi for coolant, and the transmission fluid) are the ones owners most often skip — on a lower-mileage example, assume the original fluids are still in it and check them first.

Every 7,500 miAccelerator Pedal (inspect) · Body Latches, Locks & Hinges (lubricate) · Brake Shift Interlock Solenoid (inspect) · Brake System (inspect) · Engine Oil (inspect fluid level) · Engine Oil Life Monitor (inspect)
Every 22,500 miCabin Air Filter (replace)
Every 45,000 miEngine Air Filter Element (replace) · Fuel Evaporative Emission Control System (inspect)
Every 60,000 miSpark Plugs (replace)
Every 97,500 miSpark Plug Wires (inspect) · Transfer Case Assembly (drain & refill)
At 150,000 miAccessory Drive Belt (inspect) · Drive Axle Assembly (drain & refill) · Engine Coolant System (drain, flush & refill) · Hybrid Inverter (drain, flush & refill coolant)

Reliability & federal safety record

Owner-reported issues, recalls, investigations and service bulletins on record with NHTSA — an unfiltered look at what owners actually experience.

The Cadillac CT6 generation shows a fluctuating complaint trend, peaking in 2017 with 26 reports before declining. The 2018 model year represents a low point in this arc, recording only 10 complaints, which is the lowest figure across the 2016-2020 record. While recalls remained stable at two for 2018, the volume of Technical Service Bulletins began a steady decline from 1,313 in 2017 to 1,092 in 2018. Complaints for the 2018 model were concentrated in the Power Train and Engine categories, though the data does not specify the root causes. Notably, there were zero reported crash or fire complaints for this target year. Given it has the lowest complaint volume of the generation and a downward TSB trend, 2018 is a good year to buy.

2
Open recalls
NHTSA campaigns
1092
Service bulletins
Manufacturer communications
0
ODI investigations
Office of Defects Investigation
10
Owner complaints
0 involved a crash · 0 a fire
Owner complaints by model year NHTSA · this generation & adjacent

Owner complaints filed with NHTSA, by component

All 10 complaints on record, top 8 components.

Power Train2
Engine1
Steering,Suspension,Structure1
Service Brakes,Engine1
Exterior Lighting1
Steering,Forward Collision Avoidance,Lane Departure1
Power Train,Engine,Fuel/Propulsion System1
Steering,Electronic Stability Control (Esc),Engine1

Source: NHTSA Office of Defects Investigation complaint database.

Recalls NHTSA · verified

Showing 2 of 2 campaigns on record for this vehicle.

18V673000Seat Belts:Rear/OtherReported 26/09/2018

General Motors LLC (GM) is recalling certain 2018-2019 Cadillac CT6, Escalade ESV, Chevrolet Suburban, Volt, and GMC Yukon XL vehicles. Certain second-row or third-row rear seatbelts retractor assemblies may not… Remedy: GM will notify owners, and dealers will inspect the rear seatbelt retractors and replace them if necessary, free of charge. The recall began November 7, 2018. Owners may contact…

18V437000Seats:Mid/Rear AssemblyReported 28/06/2018

General Motors LLC (GM) is recalling certain 2016-2018 Cadillac CT6 vehicles. The inboard child seat anchorage bars may have had excess structural adhesive applied during assembly, which can interfere with the… Remedy: GM will notify owners, and dealers will inspect, remove any excess adhesive, and apply anti-corrosion primer to the inboard child seat anchorage bars, free of charge. The recall…

Technical service bulletins NHTSA · verified

Showing 5 of 1092 bulletins on record with NHTSA.

BulletinDateComponentSummary
PIT3271Q2026-04-01Unknown Or OtherThis preliminary information communicates information about how to determine if a wheel…
PIP61042026-03-09Unknown Or OtherThis Preliminary information communicates the steps on how to save a GDS2 Session Log and…
PIP4902V2026-03-09Unknown Or OtherThis preliminary information advises a dealer on how to email GDS2 session logs into…
PIP5700G2026-01-12Unknown Or OtherThis PI communicates the proper part numbers for transmission connectors and internal…
PIP4902U2026-01-08Unknown Or OtherThis preliminary information advises a dealer on how to email GDS2 session logs into…

Common OBD-II trouble codes

The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.

P0420
Catalyst system efficiency below threshold — Bank 1
P0300
Random / multiple cylinder misfire detected
P0171
System too lean — Bank 1
P0455
Evaporative emission system leak detected — large leak
P0128
Coolant thermostat below regulating temperature
P0442
Evaporative emission system leak detected — small leak

VIN tools

Decode factory build data for a specific vehicle by VIN.

VIN
Decode a VIN to confirm the transmission and build data for a specific CT6. OEM
Build data
Plant, GVWR class, engine and body data for any 17-character VIN.
Recalls
Check open recall campaigns against a specific vehicle by VIN.

Vehicles with shared specs

Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.

Reference guides

Cross-vehicle references for the kinds of data on this page.

Frequently asked

How much oil does the 2018 CT6 take?

6.0 qt of 5W-30 Use GM Dexos 1 Oil or equivalent, per the factory manual.

Does the 2018 CT6 have open recalls?

NHTSA lists 2 recall campaign(s) for this model year. Check your specific vehicle by VIN.

What gas mileage does the CT6 get?

EPA figures are 22 city / 30 highway / 25 combined mpg.