2018 Caterpillar 320 Bolt Sizes & Torque Specs

Free OEM-referenced torque and bolt specs for the 2018 Caterpillar 320.

This page is the OEM-referenced fastener summary for the 2018 Caterpillar 320. Use it before any maintenance or repair job where torque values matter — brake work, wheel changes, suspension service, engine teardowns, or oil changes. Specs are pulled from manufacturer service literature, cross-checked against community data, and updated as new chassis variants become available.

For the 2018 Caterpillar 320, fasteners follow metric standards typical of late-model Caterpillar engineering. Always confirm spec against the factory service manual before tightening safety-critical fasteners (suspension, brake, steering, head bolts).

Common fastener categories on the 2018 Caterpillar 320

Wheel / lug nut torque and thread spec (covered above)
Brake caliper bracket bolts (typically 80-130 ft-lbs) and slide/guide pins (18-35 ft-lbs)
Engine oil drain plug torque — rarely above 30 ft-lbs; always use a new crush washer
Transmission pan, valve cover, and intake manifold bolts (low torque, often 89-106 in-lbs)
Suspension control arm, sway bar, tie rod end and ball joint torque
Spark plug torque (typically 10-15 ft-lbs on aluminum heads — do not exceed)
Differential cover bolts (RWD/4WD only) and transfer case fasteners

Repair guidance for this model year

For 2018 model-year work: This era introduced widespread torque-to-yield (TTY) bolts on head, main, and crank pulley fasteners. TTY bolts stretch permanently when torqued and must not be reused — the spec calls for a fresh bolt every time. Always verify TTY status against the FSM before reassembly.

Tools you will need

Metric socket set (8mm-22mm), 6-point impact-rated
Calibrated torque wrench (10-150 ft-lbs covers most automotive jobs; add a 0-250 ft-lbs wrench for truck lug nuts)
Breaker bar (24" minimum) for initial loosening
Penetrating oil (PB Blaster or Kroil) for any fastener over 5 years old
Anti-seize on stainless or dissimilar-metal threads; thread-locker (Loctite blue) on critical reassembly

Frequently asked questions

What is the lug nut torque on a 2018 Caterpillar 320?

Manufacturer-specified torque values for the 2018 Caterpillar 320 are in the factory service manual or owner's handbook. WhatSizeBolt sources values from manufacturer literature and verifies against community data — if we do not have this exact year listed, check the Caterpillar brand page for the closest model year.

What socket size do I need for the 2018 Caterpillar 320 lug nuts?

Most modern Caterpillar vehicles use a 19mm or 21mm socket. Older Caterpillar models from before 2000 may use a 13/16" SAE socket on certain trims. Confirm against the actual lug before purchasing aftermarket wheels.

Are the 2018 Caterpillar 320 fasteners metric or SAE?

Metric is the standard for this vehicle. Most fasteners on this vehicle are metric (M6, M8, M10, M12, M14). Bring a full metric set; SAE substitutes can round the head. Bolt-head markings are the fastest way to confirm grade and material at the bench.

Other Caterpillar 320 years

Same model, different model year — fastener spec may change. Always confirm against the year for your VIN.

→ 2018 Caterpillar 320 oil drain plug torque & size

→ 2018 Caterpillar 320 engine & transmission mount torque specs

All 15 2018 Caterpillar 320 fastener specs

Per-bolt torque, wrench size, and thread spec for the 2018 Caterpillar 320, sourced from OEM service literature and verified against community shop data. Values pair imperial (ft-lb) and metric (Nm) where the manufacturer publishes both.

engine — 2018 Caterpillar 320

Engine bolt-by-bolt torque for the 2018 Caterpillar 320, including the long block, valve covers, and intake. plan for a M16 tool on a M16x2.0 stud; final torque is 220 Nm / 162 ft-lbs (engine mount bolt (front)). Engine mount bolt (rear) tightens to 220 Nm / 162 ft-lbs, takes a M16 driver, runs on M16x2.0 threads. The engine oil drain plug uses a M22 drive on a M22x1.5 thread, torqued to 70 Nm / 52 ft-lbs. The fuel filter housing bolt torques to 22 Nm / 16 ft-lbs (M8 drive, M8x1.25 thread). plan for a M8 tool on a M8x1.25 stud; final torque is 10 Nm / 7 ft-lbs (air filter housing clamp bolt).

undercarriage — 2018 Caterpillar 320

undercarriage fasteners on the 2018 Caterpillar 320. Idler recoil spring nut tightens to 750 Nm / 553 ft-lbs, takes a M36 driver, runs on M36x3.0 threads. The sprocket mounting bolt uses a M20 drive on a M20x2.5 thread, torqued to 490 Nm / 361 ft-lbs. The track shoe bolt torques to 490 Nm / 361 ft-lbs (M20 drive, M20x2.5 thread). plan for a M12 tool on a M12x1.75 stud; final torque is 98 Nm / 72 ft-lbs (final drive cover bolt).

hydraulics — 2018 Caterpillar 320

hydraulics fasteners on the 2018 Caterpillar 320. The control valve mounting bolt uses a M10 drive on a M10x1.5 thread, torqued to 47 Nm / 35 ft-lbs. The hydraulic pump mounting bolt torques to 78 Nm / 57 ft-lbs (M12 drive, M12x1.75 thread). plan for a M16 tool on a M16x2.0 stud; final torque is 185 Nm / 136 ft-lbs (swing motor mounting bolt). Hydraulic oil drain plug tightens to 120 Nm / 89 ft-lbs, takes a M30 driver, runs on M30x2.0 threads.

attachment — 2018 Caterpillar 320

attachment fasteners on the 2018 Caterpillar 320. The bucket link pin retainer bolt torques to 78 Nm / 57 ft-lbs (M12 drive, M12x1.75 thread). plan for a M16 tool on a M16x2.0 stud; final torque is 220 Nm / 162 ft-lbs (boom foot pin retainer bolt).

New to torquing wheels? Read our How lug nut torque works — the complete guide for star-pattern sequence, re-torque intervals, and how to read a lug spec — then use the 2018 Caterpillar 320 numbers above.

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