Muncie SG Series PTO parts

SG Series at a glance

Type

Single speed, single gear PTO with cable shift

Mounting

SAE 6-bolt standard mount (6S)

Speed ratio

One ratio, code 10 (1:1)

Top rating

130 lb ft and 25 hp at 1,000 rpm, intermittent

Shaft options

7/8 inch round, 2 1/4, 3 1/2 or 5 3/4 inch long

Main parts book

SP86-05 SG Series Service Parts Manual

What the SG is

The SG is the simplest PTO in Muncie's gear shift range: one gear set, one speed ratio of 1:1, and a cable shift. It bolts to an SAE 6-bolt standard opening. Muncie rates it at 130 lb ft and 25 hp at 1,000 rpm intermittent, with a maximum speed of 2,500 rpm.

Because there is only one ratio, the gear and shaft you need depend on the transmission it was built for. That is why the parts list is organised by input gear code rather than by ratio.

Where it fits

The SG was built for a long list of transmission families. Muncie's gear data lists Clark (C57, C61, C70, C76), Fuller (F61), GMC (G70, G73), New Process (N70, N71, N81), Spicer (S61, S70, S72), universal gears (U57, U67, U68), Warner (W80) and Zed F (Z10, Z99). If you do not know the code, the gear letter and number in the model number tells you which transmission family the PTO was made for.

Reading an SG model number

An SG tag reads: series, mounting, input gear, ratio, shift type, assembly arrangement, shaft, special feature. Muncie's example is SG 6S-U68 10-C 1 A X: an SG on an SAE 6-bolt standard mount, universal U68 gear, ratio 10, cable shift, arrangement 1, an A shaft and no special feature.

• Shaft: A is 7/8 inch round by 2 1/4 inches long, J is 7/8 inch by 3 1/2 inches long, H is 7/8 inch by 5 3/4 inches long (G73 units only), and I is a 1 inch round shaft (GB10 only).
• Assembly arrangement: 1 or 2.
• Shifter: C, cable.

The model number guide lists the tags for every series.

Parts that wear and what to order

The SG parts list is a single list of parts plus a gear and shaft chart, so use the model number to read across it.

• Gear and shaft pair from the Gear and Shaft Part Numbers chart, by model. Each model lists its gear, its tooth count and its keyed shaft.
• Needle bearings. Muncie's service tips say to replace the closed end needle bearing with a new one whenever the PTO is apart.
• Gasket and seal kit and overhaul kit, plus the 0.010 and 0.020 inch mounting gaskets that set the backlash.
• Cable parts. The cable mounting kit, the 10 inch cable and the knob are listed separately.
• Stud kit, indicator light kit and shift components such as the yoke, trigger, poppet and spring.

Questions we get about the SG

Are Woodruff key shafts and hex key shafts interchangeable?

The parts book says the Woodruff keyed shafts directly replace the older hex key shafts. When you swap, you also need two clip rings and one Woodruff key.

Can I run a lever on a cable shift SG?

No. Muncie's owner's manual says cable shift PTOs are meant to be shifted only by wire cable. Attaching lever linkage can damage the shifting parts and, in turn, the transmission. Keep cable bends to a 6 inch radius or larger.

Can I switch arrangement 1 to arrangement 2?

Muncie lists a conversion procedure: pull the output shaft, rotate the intermediate gear 180 degrees, and move the poppet and spring to the opposite hole in the shift trigger area before putting it back together.

SG Series parts breakdown

How the Muncie SG 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 SG Series

SG Series manuals

All SG Series books: Muncie PTO parts manuals.

Need a complete rebuilt unit?

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