Michigan 280 1974 Parts Catalog – OEM Exploded Views & Part Numbers

Description

If you are tracking down a part for a Michigan 280 1974 Parts Catalog tractor dozer, you already know the frustration of mismatched aftermarket diagrams and wrong part numbers. This is the actual OEM manual from Clark Equipment – the same book the dealer used. 201 pages of exploded views, part callouts, and serial number ranges that tell you exactly which nut, bolt, or seal goes where. No reprints, no generic drawings, just factory data from 1974.

Why This 1974 Parts Catalog for the Michigan 280 Matters on the Shop Floor

Every time a tech orders the wrong air compressor governor for a 280, you lose billable time and patience. This manual lists every engine accessory – Cummins and G.M. – with original Clark part numbers. Need the air brake valve assembly? It is on page 90 alongside the brake pedal linkage. The index runs 10 pages long; you can find any subassembly in seconds. Serial number ranges (280 CUMMINS 32123-32999, 1MC156-3MC999 and 280 G.M. 1MG1-3MG999) are printed right on page 1 so you match the correct revision.

Engine (Cummins and G.M.) – Part Number Traceability

The manual devotes pages 1 and 2 to Engine Accessories for both the Cummins and G.M. diesel options. Air cleaner assemblies, connections, tailpipe, exhaust pipes, hood panels – all keyed to the same exploded view. If you are pulling an air compressor governor, the part reference is under “Air Compressor Governor” with page numbers 93, 95, 99. No guesswork. The Valve control levers and linkage are cataloged on pages 140-142, with separate control valve assembly breakdowns on pages 137-139. Use the original diagrams to match every spring and seal.

Brake System: Slack Adjusters, Air Chambers, and Valve Assemblies

Brake systems on these dozers are not forgiving. The manual lists the Brake Slack Adjuster on pages 66, 77, 86. Air Brake Valve on page 90. Brake Air Chamber on pages 68 and 77. Parking brake controls are separate – pages 87-90. When you are rebuilding the rear axle assembly (pages 73, 77) and need to tie in the brake lines, the Air Lines section references pages 93, 95, 99. One mistake in routing and you are bleeding air for an hour. Use the factory routing diagrams to get it right the first time.

Use the Index and Serial Number Ranges Correctly

Flip to the index on page 3 (after the title page and ordering instructions). It lists every component alphabetically with page numbers. Do not ignore the machine serial number range printed on page 1. If your 280 has a G.M. engine with serial number 2MG455, the parts listed under “Engine Accessories – G.M.” on page 2 are the ones you need. Ordering parts without verifying the serial number will get you the wrong axle tie rod (pages 103-105) or the wrong converter filter cartridge (pages 56-59). The manual even tells you how to contact your Clark distributor – and to always furnish the serial number.

Real-World Application: Restoring a 280 Tractor Dozer

I have seen guys buy a Michigan 280 that sat in a field for twenty years. They pull the blade assembly and find the “C” Frame trunnion bar worn out. That assembly is on pages 7-8. Main cutting edge and end bits are on pages 10-11. The lift cylinder shroud and reservoir dipstick are shown on the line drawing on page 2. Without this catalog, you are measuring threads and guessing at part numbers. With it, you call your Clark dealer, give him the part number from the manual, and get the correct seal kit in two days. This manual also lists the converter charging pump on page 61 and the steering oil filter cartridge kits on pages 109, 111, 113 – critical for a drivetrain rebuild.

Source Validity: OEM Clark Equipment vs. Aftermarket Reprints

Aftermarket parts catalogs often redraw diagrams and miss details. This is a direct scan of the original Clark Equipment publication – item number 1754-R1, revised June 1974. Printed in the U.S.A. by Clark. Every page matches the parts used on the production line. The 201-page binder includes the full index, exploded views, and part number tables. For comparison, look at the Michigan Model 280 Tractor Dozer Parts Manual No. 701 or the Michigan 280 Parts Catalog – OEM Clark Specs | 180 Pages if you need a different revision. For other Clark-era equipment, check the VOLVO BM 125C Wheel Loader Parts Catalog. If you want to understand the broader Automotive Industry Overview and how heavy equipment fits in, that context helps – but for the 280, this manual is all you need. Automotive Industry Overview

Does this manual cover both Cummins and G.M. engine versions?

Yes. Engine Accessories for Cummins is on page 1, for G.M. on page 2. Air cleaner connections differ, and each section lists the correct part numbers by serial number range.

Can I order parts directly from the part numbers in this catalog?

Yes. Clark Equipment designed this for dealers. Call your Michigan distributor, give them the quantity, part number, and description from the manual. They will cross-reference your serial number.

Are torque specifications included for the brake system or axle bolts?

This is a parts catalog, not a service manual. It does not list torque values. For that you need the separate service manual – but the parts catalog gives you the correct fastener part numbers so you can buy OEM bolts.

What about the blade cylinder assemblies – are they in here?

Blade pitch cylinder assembly is on page 134. Lift and tilt cylinders are referenced in the “C” Frame and Blade section starting on page 10. All part numbers and illustrations are original.

If you own a Michigan 280 Series I, you need the factory part numbers at your fingertips. Stop wasting time with aftermarket catalogs that skip serial number splits. Access the Factory Manual now and get the same reference your Clark dealer uses every day.