Description

Dana Spicer CM49, ES42-5, ES52-5 1988 Service Manual

If you’re working on a Dana Spicer ES42-5, ES52-5, or CM49 transmission from the late 80s, you already know the problem. Aftermarket manuals skip the fine print – like which side of the synchronizer faces forward. You guess, and you’re tearing it back apart. This 32-page factory service manual from 1988 gives you the original Dana Spicer specs, not a paraphrase.

Specifications for ES42-5 and CM49

GVW ratings appear on page 2. On-highway: 50,000 lbs. On/off: 35,000 lbs. Torque capacity is 420 ft-lbs. Page 2 lists ES42-5 specs; page 3 covers ES52-5 and CM49. Gear ratios for the 4054-A and D variants – 7.22 first gear, 86% step down to second. The ES42-5D has a different second-to-third step than the A model. Section I also covers synchronizer information and driver instructions. Don’t assume all Spicers are the same. Understanding Manual Transmission basics helps, but you still need specific factory data for these models.

What Does the Disassembly Section Cover?

The disassembly section (Section IV) opens with an exploded drawing of the clutch housing and input shaft on page 9. That’s your roadmap. The case group drawing on page 10 shows every snap ring and spacer. If you skip the inspection step on page 20, you’ll miss the bearing preload spec. I’ve seen guys install a mainshaft without measuring endplay – then wonder why it whines. The manual tells you exactly where to put the dial indicator. OEM spec, not aftermarket guesswork.

32 Pages of Factory Data

This isn’t a thick binder. It’s 32 pages, every one of them packed. Section II covers lubrication – the right oil capacity for diesel vs gas versions (200 lbs vs 188 lbs weight difference matters for fluid volume). Section III shows shift tower and remote control adjustments. Page 6 has disassembly precautions on towing – you disable the driveline or you damage the synchronizer. That’s the kind of detail that saves a Saturday.

Page 6 covers towing precautions.

Check the Torque Specs on Page 20

Page 20 is the money page. Inspection Procedures & Torque Specifications. You don’t get that in a Chilton’s. Official Dana Spicer values for flange bolts, input shaft nut, and bearing retainers. The manual also includes the synchronizer inspection – what to look for in worn bronze pads. If you’re rebuilding one of these transmissions, you need this page open on your bench. Anything else and you’re gambling.

OEM Source: Why Aftermarket Manuals Fail

I’ve had customers bring in copies from third-party sellers. The ratios are wrong, the diagrams are blurred, and the torque specs are often from a different model year. This is an original factory PDF, scanned from Bulletin No. 2363. The OCR is clean, the tables are readable. When I need a spec for a Spicer CM49, I don’t reach for a generic. I use the source. Manual Transmission maintenance depends on accurate data – this manual has it.

Who needs this? Shops that service medium-duty chassis – Ford F-600, International loadstars, old GMC Topkicks. Fleet mechanics who see Spicer ES42-5 units in delivery trucks. Home garage guys swapping a transmission into a project truck – don’t think you can wing it. The shift pattern, the synchronizer timing, the clutch housing depth – all factory specified.

What models does this manual cover?

ES42-5, ES52-5, CM49, and CM40 (page 2).

Why is page 20 critical for reassembly?

Page 20 lists the official torque specifications for mainshaft components, bearing preload values, and inspection procedures for synchronizer wear and gear backlash. Without these numbers, you risk over-tightening the input shaft nut, damaging the taper, or under-tightening the flange bolts, leading to leaks or shaft play. The manual also describes how to check clearance between the synchronizer sleeve and hub – a step most aftermarket guides skip entirely. Using factory torque specs ensures the transmission lasts another 100,000 miles.

If you’ve got a Spicer transmission on the bench, stop guessing. Access the Factory Manual. Open it on your tablet or print section V – it’ll pay for itself the first time you avoid a rebuild mistake.

• Spicer CM49 Series Transmission Parts List T210-CM49
• Dana Spicer ES42-5 1990 Parts Catalog – OEM Factory Specs
• Dana Spicer 1372-A Service Manual – Factory Specs & Rebuild Guide