Description

Nissan 320, 320-U, NEW MODEL 320-U Service Manual

I’m Mike Callahan. I’ve been turning wrenches since before most of you were born, and I’ve seen more stripped threads and misdiagnosed electrical gremlins from aftermarket manuals than from bad parts. If you’re working on a Nissan 320, 320-U, or NEW MODEL 320-U, you need the factory book. Not a copy of a copy reprinted by some third-party outfit. This Service Manual is the original OEM document from Nissan Motor Co., Ltd., Tokyo. It’s 197 pages of the exact specs that left the factory. No guesswork, no “this might work” shortcuts.

You’re probably dealing with a 50-year-old truck that’s been hacked on by five different owners. The cooling system is held together with hose clamps, the carburetor leaks, and the ignition timing is somewhere in the next county. Factory manuals are the only way to bring it back to spec without chasing your tail. That’s why I keep a copy of this one within arm’s reach on my bench.

Engine and Cooling System: What the Factory Specs Actually Say

The manual opens with General Specifications on page 1. That’s your starting point for compression ratios, oil capacities, and valve clearances. The Engine section (page 1) covers the block, head, and rocker arm assembly. From there, the Cooling System (page 3) walks you through the radiator, water pump, and thermostat. I’ve had guys bring me engines that overheated because they used a 180° thermostat from a generic parts store. The factory manual gives you the correct opening temperature—and it’s not a guess.

Lubrication starts on page 10. If you’re pulling the oil pan, you need to know which gasket to use and the torque sequence for the pan bolts. Aftermarket manuals might tell you “tighten until snug.” That’s how you get leaks. The OEM manual gives you the spec in inch-pounds and foot-pounds. No ambiguity.

Fuel System and Carburetor Adjustment: Stop Guessing

The Fuel System section (page 38) includes the gasoline tank, strainer, pump, and carburetor. The carburetor adjustment procedure on page 54 is critical. I’ve seen DIYers throw a rebuilt carb on a 320-U and wonder why it won’t idle. The factory manual tells you the float level, the mixture screw turns, and the idle speed setting. It also includes the fuel pump pressure spec. Without that, you’re just guessing.

Page 39 covers the gasoline tank removal and refitting. It’s not a hard job, but one wrong bolt and you’ll have a fuel leak that’ll ruin your day. The manual shows the correct sealant and torque for the sending unit. Trust the factory.

Transmission Assembly: Get the Order Right

The Transmission section (page 76) is where most aftermarket manuals fall apart. They’ll show you a generic exploded view and say “reverse order of removal.” That’s useless. This manual gives you the assembly order for the case (page 81), the full transmission assembly (page 87), and the selector and cross shaft (page 91). There’s a specific washer thickness and snap ring selection procedure that you won’t find in any third-party book. If you’re rebuilding a 4-speed manual, you need the factory preload specs. Page 87 has them.

For more context on manual transmission design, see Manual Transmission. And if you’re working on a later model, check out Nissan Xterra 2005 Service Manual – OEM Factory Spec.

Brake and Ignition Timing: Safety First

The Brake section (page 138) covers the hydraulic system, wheel cylinders, and adjusters. You don’t “eyeball” brake adjustment. The manual gives you the shoe-to-drum clearance and the bleed sequence. Messing that up can cost you a crash.

Breaker Point and Ignition Timing Adjustment (page 59) is a dying art, but these trucks have points. Page 59 covers the distributor, page 61 the timing adjustment, and page 65 plug checks. The dwell angle is spec’d in degrees. Use a dwell meter, not a feeler gauge. The factory manual tells you why.

For an overview of the automotive industry’s evolution, see Automotive Industry Overview.

Why This OEM Manual Beats Aftermarket Copies

Every page in this Service Manual was written by Nissan engineers. The wiring diagrams are exact. The torque values are the ones used on the assembly line. Aftermarket manuals often reprint outdated specs or leave out critical notes—like the fact that the 320-U had a different front axle tension rod setting (page 114) than the base 320. This manual includes that detail. It also covers the NEW MODEL 320-U variant, which some aftermarket books ignore completely.

If you need the original factory bulletin for a 1967 Nissan 60, see Nissan 60 1967 Service Manual – Original Factory Bulletin. And for a direct link to this manual’s sibling, check NISSAN 320 Service Manual.

Does this manual cover the NEW MODEL 320-U?

Yes. The manual is titled for all three variants: 320, 320-U, and NEW MODEL 320-U.

How many pages does it have?

197 pages, including the specification, engine, cooling, fuel, transmission, brake, electrical, and more.

Why should I use this over a Haynes manual?

Haynes manuals are generic. They cover a range of years and often omit year-specific torque specs. This OEM manual is written for these exact models. It includes the correct ignition timing for the 320-U, the precise carburetor adjustment for the NEW MODEL, and the factory assembly sequence for the transmission. You won’t find a note about “if you have a different gear ratio, use this shim” in a Haynes. This manual has it. The difference is the difference between a job that lasts and one that comes back on a tow truck.

Is the electrical system wiring diagram included?

Yes. The Electrical System section starts on page 150 and covers the starter motor (page 164), battery, and all wiring. Full schematics are in the manual.

You’ve got two choices: keep chasing old wiring diagrams from forum posts, or get the one document that shows exactly how Nissan built this truck. Access the Factory Manual and put it on your tablet—or print it out for the shop. Either way, you’ll have the real specs, not a guess.