Description

Mitsubishi 4G63 Service Manual – Rear Axle Section

Mitsubishi 4G63 Service Manual – if you’ve ever pulled a rear axle on a 2WD 4G63 or fought with a limited-slip differential that wouldn’t behave, you know the pain of guessing specs. The aftermarket CD-ROMs I’ve seen list torque values that might be close for a Chevy but not for this banjo-type housing. This 60-page factory document is the only source I trust when checking axle shaft axial play or measuring limited slip preload on the 4G63. It’s the same binder the dealer techs had, and it covers the exact steps for both drum and disc brake setups – including the ABS rotor press-fit detail that most third-party manuals miss.

General Information & Service Specifications (Page 2–4)

The first section lays out the rear axle type: banjo semi-floating with single-taper bearings for standard 2WD and 4WD panel vans, double-taper for ABS-equipped wagons. The table on page 2 shows axle dimensions – 38.1 mm bearing OD for non-ABS, 40.0 mm for ABS – and lists the differential reduction ratios. For the 4G63 2WD standard wheelbase, the drive gear has 39 teeth and the pinion 8, giving a 4.875 ratio. Page 4 gives the service specifications: oil level check procedure, gear oil type, and the limited-slip differential preload measurement range. You need those numbers before you touch a single bolt, or you’ll be pulling the carrier twice.

Service Adjustment Procedures: Backlash, Axial Play, and ABS Differences

The adjustment section (page 10) covers the rear axle total backlash check and axle shaft axial play check. For vehicles without ABS, the axial play adjustment is straightforward – shim selection based on the measured clearance. But the manual specifically notes that vehicles with ABS use a double-taper bearing and a press-fitted ABS rotor, which changes the play specification. I’ve seen techs skip the ABS distinction and end up with a loose axle that chatters. Page 10 also includes the limited-slip differential preload measurement – a torque-responsive mechanical type that requires a specific preload on the clutch packs. Get it wrong and the LSD won’t lock properly on slick pavement.

Axle Shaft Options: Drum Brake vs. Disc Brake (Pages 17 & 25)

Two separate sections cover axle shaft removal and installation depending on your brake type. The drum brake procedure (page 17) involves pulling the brake shoes and the backing plate hub, while the disc brake version (page 25) requires removing the caliper and rotor first. Both paths include the oil seal replacement steps – page 12 shows the axle housing oil seal replacement with the correct seal driver tool part number from the special tools list (page 7). If you try to hammer in a generic seal without the right pilot, you’ll damage the housing bore. The manual also lists the required sealant – 3M ATD Part No. 8660 or equivalent – for the differential carrier mating surfaces.

Limited Slip Differential Case Assembly for 2WD 4G63 (Page 50)

Page 50 is dedicated to the LSD case assembly specifically for 2WD vehicles with the 4G63 engine. The limited-slip differential uses a torque-responsive mechanical type with straight bevel side gears (2 or 4 depending on option). The manual shows the exact order of clutch plates, spacers, and the pinion mate shaft. The preload measurement procedure on page 12 applies here – and the torque values are given in inch-pounds, not guessed. There’s also a separate LSD assembly section for vehicles without the 4G63 (page 55) to avoid confusion. Don’t mix them up; the gear ratios differ.

Source Authenticity: Factory Specs vs. Aftermarket Reprints

This is a scanned PDF of the original Mitsubishi factory manual, not a cleaned-up reprint that sometimes drops pages. The OCR excerpt shows the original page numbering and footnotes – like the ( ) notation for ABS vehicles. I’ve compared aftermarket versions that list the axle shaft bearing as “single taper” for all models, which is wrong. The factory manual calls out double-taper for ABS wagons. That kind of error costs hours on a lift. If you need a reference you can stand behind in a warranty dispute or a shop audit, you want the OEM source. For related factory documentation, check the Mitsubishi 4G63 Engine Service Manual and the Mitsubishi 4G63 4G64 Wiring Diagram – Factory Schematics Manual. For dealer training material, the Mitsubishi 4G63 4G64 2003 Training Manual – OEM Dealer Specs covers powertrain diagnostics.

FAQ

Does this manual cover the 4G63 engine itself?

No. This is the rear axle section only – 60 pages focused on axle shafts, differential, and brakes. For engine removal or timing belt specs, you need the full service manual or the Mitsubishi 4G63 Engine Service Manual.

Are the torque values given in foot-pounds or inch-pounds?

The manual uses both. For instance, the limited slip differential preload on page 12 is specified in inch-pounds (range: 80–120 in·lb), while the axle shaft locknut torque on the drum brake model (page 17) is given in foot-pounds. The service specification table on page 4 lists all torque values with their units. If you use a standard click-type torque wrench, make sure you have the inch-pound adapter for the small fasteners – the manual lists the special tools required on page 7, including an inch-lb torque wrench (MB991178).

When you’re under a Mitsubishi with a 4G63, the last thing you need is a doubt about backlash or brake rotor runout. This factory manual puts the exact procedures on your bench – from the axle shaft axial play check to the LSD preload. I’ve seen DIYers and pros alike waste half a day because they trusted a generic write-up that skipped the ABS exception. Don’t learn that lesson the hard way. Access the Factory Manual and keep it in the same drawer as your torque wrenches. For background on factory documentation standards, see the Automotive Industry Overview and the Automotive Industry Overview for context on why OEM specs matter.

Related Manuals

• Mitsubishi 4G63 Engine Service Manual
• Mitsubishi 4G63 4G64 Wiring Diagram – Factory Schematics Manual
• Mitsubishi 4G63 4G64 2003 Training Manual – OEM Dealer Specs