How to read a Muncie PTO model number

Where to find it

Look on the PTO housing for a riveted tag or a stamped model number. Paint, rust and road grime often hide it, so clean the housing before you give up. The same number appears on the box and the paperwork of a new unit. If there is truly nothing left, the bolt pattern, the transmission, the shift method and the output shaft still narrow it down, and a photo of the unit helps us a lot.

The pattern most Muncie side mount PTOs follow

Muncie's spec brochures print a "model number construction" chart for each series. For the gear shift and clutch shift side mount units the order is the same, even though every series has its own list of letters:

1. PTO type (series): TG, SH, CS, CB, 82 and so on.
2. Mounting: the bolt pattern and stud style, such as 6S for an SAE 6-bolt standard mounting or 8S for an SAE 8-bolt standard mounting.
3. Transmission input gear: a letter for the transmission family plus two digits, such as U60, F66 or A69.
4. Speed ratio: two digits, such as 04 or 13. Each code stands for a fixed output to input ratio.
5. Shift option: a letter or digit for cable, manual air, electric over air, electric hydraulic or another control.
6. Assembly arrangement: a digit for which side the output shaft sits on and how the gears face.
7. Output option: a letter for the shaft or pump mount, such as a round keyed shaft or an SAE B pump flange.
8. Special feature: a final letter, often X for none.

Worked example: a TG Series model number

Muncie's TG Series spec brochure (MP15-27) uses TG-6S-U60-04 C-1-B-X as its example. Reading it left to right:

On the tag the dashes and spaces are often dropped or moved, so the same unit can read TG6S-U6004-C1BX. Other TG codes from the same chart:

• Mounting: 6D and 6N are SAE 6-bolt non-standard mountings for the S68 and S71 input gears, 8S and 8D are 8-bolt, 8F is the 8-bolt mounting for the Eaton Endurant, and B or L in the second place mean metric studs or no stud kit.
• Input gears: A69 Allison, E70 and E80 Eaton, F63, F66 and F70 Fuller, M65 Mack, S71 Tremec or Spicer, S68, U60 and U68 universal.
• Speed ratios: 04 is 0.361, 05 is 0.470, 06 is 0.613, 07 is 0.724, 08 is 0.885, 09 is 0.923, 12 is 1.170, 13 is 1.333, 15 is 1.500 and 18 is 1.720.
• Shift options: A is 12 volt manual air, C cable, E 12 volt electric over air, M constant mesh, P manual air without the installation kit, and Z, 4 and 5 are the cable, air and electric over air versions for the A69 Allison gear.
• Outputs: B round keyed shaft, I DIN 5462, K SAE B 7/8 inch 13 tooth with 2 and 4 bolt flange, P SAE BB 1 inch 15 tooth, S SAE B 2-bolt, T SAE A 3/4 inch 11 tooth.
• Special features: X none, A inverted air cover, G greaseable shaft, H and J high torque versions, I dual terminal indicator, P pressure lube.

Clutch shift units: CS or CB

On the CS6 and CS8 family the first letters also tell you about the brake. Muncie's chart lists CS for a clutch shift PTO with the standard drag brake and CB for the version with the optional shaft brake. That is why the CB6 and CB8 share a parts book with the CS6 and CS8. The input gear list is longer on these units and includes Aisin, Allison, Clark, Fuller, Mack, Mercedes and Spicer codes.

Other Muncie families

The Ford, Allison, PACCAR, rear mount and split shaft units use their own model number layouts, because they only fit one transmission or have no input gear to choose. Each series page on this site explains its own number where the Muncie literature prints the chart. Start from the Muncie PTO parts page.

Why the full number matters

Two TG units that look identical can have different input gears, ratios and output shafts, and the gear set, shift cover and seals follow those codes. With the full model number we can pull the exact parts from the series breakdown. With only "it is a TG" we have to ask more questions, and you wait longer.