Description

Dana Spicer AUX 1241 1000 Series 1991 Parts Catalog – OEM Factory Specs

You’re hunting a part number for a Spicer AUX 1241 and the online listings give you three different bearings. Which one is right? This Dana Spicer AUX 1241, 1000 Series 1991 Parts Catalog settles it. Published August 1991 under Bulletin T210-AMO1000-4, 53 pages of factory parts breakdowns. No aftermarket guesswork – these are the same illustrations and part numbers the Spicer engineers used.

Page 3 shows the full gear train breakdown for the AMO/APO1000-4 models with Manual and Air-Matic shift. Every bearing, snap ring, thrust washer, and mainshaft variant is listed with its Dana part number. Need a drive gear group? Ref A-1 gives you 98-35-1 or 98-35-3 depending on 38T vs 25T input. That level of detail saves you ordering the wrong piece and having a transmission sitting on the bench waiting.

AUX 1241 and 1000 Series Parts Catalog – What You Get

This is a parts catalog, not a service manual. It tells you which part goes where, but not how to install it. You get exploded diagrams for the main gear train, clutch collars, companion flanges, and shifter housing components. The catalog covers base B/M numbers 300977, 300978, 301145, and 301146, plus all related shifter housings. If you work on these Spicer auxiliaries in a shop, this is the reference you pull when a customer brings in a unit with a stripped mainshaft or a missing snap ring.

Three related factory catalogs you should check: Dana Spicer ES42-5 1990 Parts Catalog – OEM Factory Specs, Dana Spicer T20000 2005 Parts Catalog – OEM Factory Specs, and Dana Spicer T210 CM55 1991 Parts Catalog – OEM Factory Specs. Each covers different transmission families but with the same factory spec approach.

What Makes This Catalog Different from Aftermarket Lists?

Aftermarket part databases merge multiple revision levels into one line. They’ll show a superceded part number without telling you which serial number range it fits. This catalog gives you the original part numbers and the exact notes – like the B-1 mainshaft listing on page 3 that tells you which base B/M uses 98-362-1 vs 98-362-3 vs 98-362-2. The note says “with Shifter Housing 98-16-4” or “for all other Base B/M’s.” That distinction matters when you’re trying to get a unit back together without buying three different shafts.

Worth noting: some parts like the old-style clutch collar (98-465-4) are marked “no longer available” with a service kit replacement. The catalog footnotes that too.

Gears and Related Parts: What Page 3 Covers

Page 3 is the meat of this catalog. It lists ref numbers A-1 through A-9 and B-1 through B-17 for the gear train. Drive gear groups, pocket bearings, rear bearings, spacers, slingers, baffles, nuts, and the mainshaft output assemblies. Every part has a Dana Spicer part number, description, and quantity. For example, the input shaft front bearing uses 550908 for AMO/APO1000-4 models, but a different bearing for the 1241/P1241 one-piece drive gear units. If you mix them up, the bearing will walk out of the bore. This catalog keeps you straight.

For a broader understanding of drivetrain technology, see the Automotive Industry Overview and Internal Combustion Engine articles. They cover the context these transmissions work in.

Understanding the Part Numbering System

Spicer part numbers in this catalog follow a pattern. Five or six digits, sometimes with a dash suffix like -1X for service kits. The catalog uses “or” between alternatives to indicate model-specific differences. Double-check the model suffix – AMO means manual shift, APO means air-matic. The drive gear group for a 1241 (one-piece) is different from a P1241 (two-piece). If you ignore that, the snap ring won’t seat.

Who Needs This Catalog – Shop Owners and DIY Rebuilders

If you run a shop that touches any Spicer auxiliary transmission from the 1000 Series or the AUX 1241, you need this on a tablet or printed out. The 53 pages cover the exact parts breakdowns for the AMO/APO1000-4 models. The DIY builder pulling a salvage-yard unit will use this to identify missing hardware and order the correct seals and bearings without tearing the thing apart twice. Don’t rely on a generic online lookup – this is the actual factory document that Spicer transmission techs used.

Small paragraph: This catalog is not a substitute for a service manual. It gives you the part numbers; you still need torque values and assembly procedures from the factory service manual.

FAQ

What models does this catalog cover?

AUX 1241 and 1000 Series with Manual/Air-Matic shift.

How do I find the correct mainshaft part?

On page 3 you’ll see B-1 mainshaft options with three part numbers: 98-362-1, 98-362-3, and 98-362-2. Each corresponds to specific base B/M numbers and shifter housing versions. You must match your unit’s serial number to the correct base B/M listed in the note to avoid ordering the wrong shaft. The catalog gives you that cross-reference.

Don’t lose another hour chasing wrong parts. Access the Factory Manual for the 1991 Dana Spicer AUX 1241 and 1000 Series Parts Catalog – the only source for bullet-tested OEM part data.