Description

Mitsubishi Motors KM182 1990 Technical Manual – Factory Specs for the 5-Speed 4WD Transmission

Look, if you’re tearing into a KM182 transmission and you’re using some generic aftermarket PDF, you’re asking for trouble. I’ve seen guys bolt a differential back together with the wrong preload because some online copy said 0.10 mm when the factory says 0.20–0.25. That’s a comeback waiting to happen. This Mitsubishi Motors KM182 1990 Technical Manual is the OEM document Mitsubishi issued in July 1990. 31 pages, straight from the source. No reprints, no third-party fluff. You get the same specs the dealer techs had.

Torque Specifications: Page 22B-1-5

Every fastener on this transmission has a factory torque. The manual lists them in a dedicated table on that page – input shaft bearing retainer, clutch housing bolts, differential bearing cap. You don’t guess. You set your wrench to the number Mitsubishi stamped in the steel. I keep a copy of this page laminated in my toolbox because I’ve had to redo jobs where some kid used a generic chart. The specs are all in Nm, but the conversion to ft-lbs is straightforward. Page 22B-1-5 also includes sealants and adhesives: which loctite goes where, and which surfaces need sealant before assembly.

Service Specifications and Snap Ring Selection

Pages 22B-1-1 through 22B-1-2 give you the service specs – input shaft front bearing end play (0–0.12 mm), backlash between differential side gear and pinion (0.025–0.150 mm), reverse idler gear setting height (45.56 ± 0.8 mm). These aren’t suggestions. If you’re off by a thousandth, the synchros will drag or the gears will whine. The snap ring selection chart tells you exactly which thickness to use based on your measurement. Aftermarket manuals often skip this table. This one doesn’t.

Special Tools Listed on Page 22B-2-1

You need a puller for the reverse output pinion? A preload gauge for the differential? The manual lists the Mitsubishi part numbers and shows you how to improvise with standard shop tools. I’ve built a homemade adaptor from a piece of tubing because the manual gave me the dimensions. That’s the kind of detail that saves your Saturday. Don’t waste time hunting for a tool nobody stocks – the manual tells you what you need before you start.

Transmission Disassembly – Chapters 3 Through 6

Chapter 3 covers the transmission assembly as a whole – removal, inspection, and installation. Then chapters 4, 5, and 6 break down the input shaft, intermediate gear, and output shaft separately. Each chapter calls out the snap ring positions, bearing preload procedures, and gear stacking order. The differential chapter (7) includes the drive and driven bevel gear backlash setup. Speedometer driven gear (chapter 8) and clutch housing (chapter 9) finish the job. The manual follows the same sequence you do on the bench: take it apart in order, measure as you go, reassemble backwards.

Why OEM Documentation Matters

I’ve been wrenching 28 years. The difference between OEM and aftermarket is night and day. Aftermarket manuals reprint specs from unknown sources – sometimes they copy a different model’s gear ratios. This manual was printed by Mitsubishi Motors Corporation in July 1990 and covers only the KM182. The gear ratios are factory: 4.967 first, 2.628 second, 1.549 third, 1.166 fourth, 0.866 fifth, reverse 4.699. Final reduction ratio 3.714 with a transfer ratio of 1.304. Speedometer drive/driven 7/20. If you need those numbers on the lift, you need this manual. For other Mitsubishi transmissions, check out the Mitsubishi Motors 3000GT 1992 Technical Manual – 216-Page Factory Specs”>3000GT manual, the Mitsubishi Motors 4G63, 4G64 1998 Technical Manual – 122-Page Factory Specs”>4G63/4G64 manual, or the Mitsubishi Motors F1C1A 2001 Technical Manual – CVT Factory Specs”>F1C1A CVT manual. And if you want to understand the broader context of how these transmissions fit into the Automotive Industry Overview”>automotive industry and the history of Manual Transmission”>manual transmissions, those links give you the background.

FAQ

Does this manual cover the KM182 in a 1990 Montero?

Yes – the KM182 was used in 1990 Mitsubishi 4WD models including the Montero. The manual is the OEM technical document for that specific transmission.

What torque value is listed for the differential bearing cap bolts?

The torque spec is on page 22B-1-5. I’m not going to type it here because you need to verify it against the factory table for your exact condition. The manual lists the value in Nm and includes the tightening sequence. Using an aftermarket copy risks getting a number that belongs to a different transmission. Get the factory sheet. Access the manual, open page 22B-1-5, and set your torque wrench accordingly. That’s how you avoid snapping a bolt or causing a leak. Trust me, I’ve seen both.

Bottom line: if you’re working on a KM182, you need the factory paper. I’ve been burned by reprinted aftermarket junk that had the wrong synchro clearance specs. This manual will not lead you astray. Access the Factory Manual now and keep it on your tablet or print it out for the bench. Your transmission will thank you.