Description

Mitsubishi 6A12, F5M42, F5A42 1998 Workshop Manual

Listen, I’ve been turning wrenches for 28 years. The worst feeling is when you’re in the middle of a clutch job and the manual tells you to “tighten to spec” without giving you the number. That’s why when I need a Mitsubishi 6A12, F5M42, F5A42 1998 Workshop Manual, I don’t mess with aftermarket garbage. This is the factory document. 189 pages of the real deal.

This manual covers the 6A12 engine—that’s the 2.0L V6—and two transmissions: the F5M42 (manual) and the F5A42 (automatic). You get the Standard Parts Tightening Torque table right up front. That table alone saves you from stripping bolts. Then the Form-in-place Gaskets (FIPG) section tells you exactly which sealant to use where. No guessing. If a gasket surface requires a specific thickness of FIPG, the manual says it.

Engine & Transmission Models

The 6A12 is a 60-degree V6 with a 24-valve DOHC setup. The manual covers the engine in full: specs, rework dimensions, torque specs, sealants. It lists the special tools you need—no more running to the parts store mid-job. For transmissions, you get the F5M42 (5-speed manual) with gear ratio tables and snap ring selection charts. The F5A42 automatic transmission includes valve body spring identification and thrust bearing arrangement drawings. This is the kind of detail that keeps you from tearing out your hair.

Torque Specs: Why You Need the Factory Numbers

Aftermarket manuals love to print generic torque values that don’t match Mitsubishi’s fasteners. This manual gives you the exact torque specs for the cylinder head, main bearing cap, connecting rod, flywheel bolt, drive plate bolt, and every transmission fastener. The Torque Specification subsection under Engine is your reference. Also the Standard Parts Tightening Torque table covers common bolt grades. Use it. Don’t trust a 10mm socket and a wiggle test.

Does This Manual Cover the Fuel System?

Yes. The Fuel and Emission Control chapter includes installation service points for the fuel lines, injectors, and emission components. If you’re working on a 6A12 with a faulty injector or a vacuum line routing problem, the manual shows the correct orientation. It also includes the ignition system section with firing order and component locations. The fuel system is not an afterthought here—it’s documented the same way as the engine block.

Remove and Install the Timing Belt

The Timing Belt chapter is four pages of pure procedure. It covers removal, installation, inspection, and the auto tensioner. The auto tensioner procedure requires a pin to lock the mechanism—if you don’t preload it correctly, the belt jumps time. The manual tells you the exact torque for the tensioner pulley bolt and the sequence for tensioning. Do not skip the inspection step where you check for oil leaks from the cam seals. The manual calls for the alternator drive belt to be removed first—it lists that step.

7 Sections in the Manual Transmission Chapter

If you are rebuilding the F5M42, the manual breaks it down into: General Information, Specifications (with gear ratio table), Special tools, Disassembly & Re-assembly (with service points), Input Shaft, Output Shaft, Reverse Idler Gear, Speedometer Gear, Select Lever, Control Housing, Clutch Housing, Transmission Case, and Differential. Each section has service points for disassembly and re-assembly. The snap ring thickness chart ensures you select the correct preload on the bearings. This level of detail is rare even in factory manuals.

Clutch Service Points: Release Bearing and Fork Installation

The Clutch chapter includes removal and installation service points, torque specs for the pressure plate bolts, and the release bearing installation procedure. The release cylinder disassembly shows the exact order of seal removal. If you don’t bleed the system correctly after reassembly, the clutch won’t disengage. The manual gives the lubricant spec for the release fork pivot.

Source Validity: OEM vs Aftermarket

This is not a reprint or a scan from a third-party aggregator. It is the original OEM workshop manual published by Mitsubishi in 1998. The PDF is 189 pages of factory documentation. I’ve compared it to aftermarket versions—they leave out the Standard Parts Tightening Torque table and the FIPG section. Those omissions cause leaks and failed seals. Factory men only.

Aftermarket documentation? I’ve seen them use the same diagram for both the F5M42 and the F5A42. That’s a joke. The two transmissions share nothing internally. The manual’s Automatic Transmission chapter covers the F5A42 with its own special tools, disassembly sequence, and valve body spring identification table. The clutch chapter is separate and includes the release cylinder disassembly and inspection.

Related manuals that you might need for other Mitsubishi drivetrains: Mitsubishi R4AW2-1, R4AW2-3, R4AW2-7 1996 Workshop Manual and Mitsubishi 4D68 1996 Workshop Manual – 70 Pages of OEM Specs. For automatic transmission rebuilds on later models, check Mitsubishi F4A4 F4A5 1999 Workshop Manual – OEM Transmission Rebuild Specs.

I’ve seen techs ruin clutch packs because they used a generic automatic transmission manual. This factory manual is the only source that matches the actual parts. For an industry overview on why OEM documentation matters, see Automotive Industry Overview. Also check Automotive Industry Overview for more context on factory specifications.

If you’re working on a Mitsubishi 6A12 or the F5M42/F5A42 transmissions, stop trusting internet forum advice or cheap reprints. Get the factory data. Access the Factory Manual now and keep it on your workbench where it belongs.