Toyota 1GR-FE

The Toyota 1GR-FE is a 4.0 L (3,956 cc, 241.41 cu·in) V6, four-stroke cycle water-cooled naturally aspirated internal combustion gasoline engine, manufactured by the Toyota Motor Corporation since 2002. This engine was producted on Kamigo Plant, Shimoyama Plant, Tahara Plant and Toyota Motor Manufacturing Alabama.

The 1GR-FE engine has 6 cylinders in a V arrangement at a bank angle of 60° The 1GR-FE features a lightweight die-cast aluminum block with a four-bearings crankshaft and two aluminum heads with two camshafts (DOHC) and four valves per cylinder (24 in total). The Toyota 1GR-FE engine is equipped with SFI (Sequential Multiport Fuel Injection) system, Direct Ignition System (DIS) with individual coils on each spark plug and VVTi (Variable Valve Timing) system for the intake camshafts. In 2009, an updated version of this engine was introduced, it is equipped with Dual VVT-i system on both intake and exhaust sides.

A 94.0 mm (3.7 in) cylinder bore and 95.0 mm (3.74 in) piston stroke give the 1GR-FE engine a total of 3,956 cc (241.41 cu·in) of displacement. Compression ratio rating is 10.0:1 for engines with VVT-i and 10.4:1 for engines with Dual VVT-i.

The Toyota 1GR-FE engine produced from 240 PS (176 kW; 236 HP) at 5,200 rpm to 290 PS (213 kW; 285 HP) at 5,600 rpm of maximum power and from 367 N·m (37.4 kg·m, 270 ft·lb) at 4,000 rpm to 377 N·m (38.4 kg·m, 277.8 ft·lb) at 4,400 rpm of peak torque, depending on year and vehicle model.

The breakdown of the engine code is as follows:

• 1 – 1nd generation engine
• GR – Engine family
• F – Economy narrow-angle DOHC
• E – Multi Point Fuel Injection

General information

Cylinder block

The 1GR-FE engine has an aluminum cylinder block in a V arrangement at a bank angle of 60&deg. This engine’s firing order is 1–2–3–4–5–6. Cylinder bore and piston stroke are 94.0 mm (3.7 in) and 95.0 mm (3.74 in), respectively. Compression ratio rating is 10.0:1 or 10.4:1.

The engine has “spiny type” cast-iron cylinder liners. For the VVT-i 1GR-FE engine, the forged steel crankshaft has four main journals and nine balance weights. For the dual VVT-i 1GR-FE engine, a five balance weight crankshaft was used, the locations of the balance weights were optimized to reduce vibration.

The 1GR-FE engine used forged connecting rods with aluminum bearings. The connecting rods and caps are made of high-strength steel and used nutless-type plastic region tightening bolts. The Toyota 1GR-FE engine has aluminum alloy pistons with “taper squish” shape for the piston head. For the higher compression ratio of the dual VVT-i 1GR-FE engine version, the shape of the pistons was optimized.

The Toyota 1GR-FE motor has two compressions and one oil control rings. The groove of the top piston ring is coated with anodic oxide to improve wear resistance and rust resistance, and the piston skirt is coated with resin to reduce friction. Oil-cooling jets under the pistons acted to reduce piston temperatures.

Main bearing cap bolts tightening procedure and torque specs:

• Step 1: 61 Nm; 6.2 kg·m; 45 ft·lb
• Step 2: Turn bolts 90°
• 12 mm head: 25 Nm; 2.5 kg·m; 18 ft·lb

After securing bearing cap bolts, make sure crankshaft turns smoothly by hand.

Connecting rod bearing bolts

• Step 1: 25 Nm; 2.5 kg·m; 18 ft·lb
• Step 2: Turn bolts 90°

Cylinder head

The cylinder heads are made of aluminum alloy with two overhead camshafts and four valves per cylinder. The 1GR-FE engine camshafts are made of cast iron alloy. Both the primary and secondary timing chains used pitch roller chains. The intake camshafts are driven by the crankshaft via the primary timing chain. The exhaust camshafts are driven by the intake camshaft of the respective bank via the secondary timing chain. For the dual VVT-i 1GR-FE, the cam lobes had indented R profiles to increase valve lift when the valve began to open and as it finished closing.

For valve actuation, the VVTi 1GR-FE engine used shimless type valve lifters. The early version of the Toyota 1GR-FE engine is not provided with hydraulic lifters, so you must control the valve clearances once in 60,000 miles (100,000 km) of mileage.

The dual VVTi 1GR-FE engine used roller rocker arms with built-in needle bearings that reduced the friction that occurred between the camshafts and the roller rocker arms. This version of the engine has hydraulic lash adjusters. Through the use of oil pressure and spring force, the lash adjuster maintained a constant zero valve clearance.

Head tightening procedure and torque specs:

• Step 1: 36 Nm; 3.6 kg·m; 27 ft·lb
• Step 2: Turn all bolts 180°
• 14 mm head: 30 Nm; 3.0 kg·m; 22 ft·lb;

Maintenance data

Valve clearance adjustment data

Calculate the thickness of new adjusting valve shim so valve clearance comes within specified values.

R = Thickness of removed valve shim
N = Thickness of new valve shim
M = Measured valve clearance

Intake:
N = R + [M – 0.20 mm (0.008 in)]
Exhaust:
N = R + [M – 0.30 mm (0.012 in)]

Valve shims are available in 35 sizes to range from 5.060 mm (0.1992 in) to 5.740 mm (0.2260 in), in steps of 0.02 mm (0.0008 in).

Example (exhaust valve):
R = 5.300 mm
M = 0.520 mm
N = 5.300 + (0.45 – 0.30) = 5.450 mm.

Vehicle applications

Author: Sergei Wers
About: Co-founder and CEO of a multi-brand auto repair shop (engine repair, chassis repair, body repair and painting) for over 15 years. I have been developing internet sites with technical specifications for more than seven years.