Muncie Alpha PTO parts

What the Alpha is

The Alpha Series, listed in Muncie's parts book as the A1, is a compact PTO made to make installation easier and give maximum clearance. The shifter is built into the housing, and the pump can mount to the front or the rear of the PTO. Muncie notes that its internal components are common to the TG Series.

Shift options are cable, manual air, electric over air and the 12 volt E-Hydra shift. The E-Hydra option is marked in Muncie's brochure as call for availability.

Where it fits

The Alpha has one input gear option, the D94, listed as Dodge Ram 9.41P and in the brochure as the Mercedes and Dodge G56-6. Muncie's brochure sets which outputs go with 4x2 and 4x4 chassis. On a 4x4 Dodge, Muncie tells the installer to detach the forward drive shaft from its yokes to make room for the PTO, then put it back in the same position.

Reading an Alpha model number

An Alpha tag reads: model and design number, mounting, input gear, speed ratio, shift type, assembly arrangement, output and special feature. Muncie's example is A1 6M-D94 04-C 1 B X: an Alpha design 1, SAE 6-bolt special mount, D94 input gear, ratio 04, cable shift, arrangement 1, a 1 1/4 inch round output shaft and no special feature.

• Ratio: 04 (0.361:1), 05 (0.470:1), 06 (0.613:1), 07 (0.724:1), 08 (0.885:1), 09 (0.923:1), 12 (1.170:1), 13 (1.285:1), 15 (1.500:1) and 18 (1.720:1).
• Shift: A manual air, C cable, E electric over air, T E-Hydra 12 volt.
• Arrangement: 1 is 4x4 with the pump to the front, 2 is 4x4 with the pump to the rear, and 4 is pump to the rear on a 4x2 only. The parts book also allows arrangement 3.
• Output: B 1 1/4 inch round, K SAE B 2 and 4 bolt, Q SAE A with 7/8 inch spline, S SAE B 2 bolt, T SAE A with 3/4 inch spline. Muncie's brochure also lists an R output, SAE A with a 5/8 inch spline.

The model number guide compares this with the other series.

Parts that wear and what to order

• Gear set by ratio from Table A, Gear Set Selection. Each ratio lists the input gear and the output gear with their tooth counts.
• Flange and seal assembly from Table B, by output option B, K, Q, S or T.
• Shift kits: the standard air shift system, the cable shift kit (with separate part numbers for 1 and 4 arrangement and for 2 and 3 arrangement), the electric over air kit, and the E-Hydra activation kit.
• Installation kit with studs. The Alpha uses six metric studs, two of them step studs.
• Gasket and instruction pack, with the 0.010 and 0.020 inch gaskets used to set backlash.

Questions we get about the Alpha

How do I check backlash on an Alpha?

The Alpha has no removable shift cover. Muncie puts two 1 inch straight thread ports in the side of the housing for the check. Take out the plug nearest the input gear, measure, then put the plugs back.

How are the studs torqued?

Muncie's supplement puts the two step studs at the 6 and 12 o'clock positions. The four standard metric studs take Spiralock nuts torqued to 40 to 45 ft lb.

How does the cable attach on a cable shift Alpha?

With the cable lever pulled away from the housing, clamp the cable about 1 to 2 inches from the end of its insulation, then feed the control wire through the bolt in the second hole from the top of the lever. Muncie's IN09-10 supplement has the figures.

Alpha A1 parts breakdown

How the Muncie Alpha (A1) Series PTO parts list is organised on our store. Each section opens the exploded view with every part number, the quantity used and an order button.

Muncie A1 Series

Alpha A1 manuals

All Alpha A1 books: Muncie PTO parts manuals.

Need a complete rebuilt unit?

Our sister site rebuiltmunciepto.com covers rebuilt Alpha A1 units. This site is the parts and model reference side.