spicergear
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Installed a shiny new PTO on 'Bruiser' (931A2) this weekend. Let me help you...this was not fun but I have some tips that will help anyone else on their install. It is a tight fit, really tight. I've heard of people pulling/dropping the transmission to install PTO's on these trucks and I just didn't feel like going through those motions.
The NewStar PTO from C&C equipment (clintdigger) looks to be a nice unit. They're on eBay and the price is very attractive. I got a quote from a Parker/Chelsea dealer on a new 271 unit and was two grand. HA! My weekend was spent under the truck, but below are some tips that I hope will help some upcoming installs.
Tip one: Find a small jack to push against transmission from frame rail to gain a little more clearance. It won't be that much...but every little bit helps. Use your head, don't use a hydraulic jack and keep pumping until you split your transmission case as this isn't making a ton of room, it's gaining a little clearance temporarily.
Tip two: Don't install the studs into the transmission like the directions say or you will not get it on unless you drop trans or loosen a bunch of other stuff. Install studs into two lower side holes of PTO. Install copper washer, locking tab, then nut...and thread nut onto stud until you bottom out at the end of the threads. What you've just effectively done is made a short bolt. Also, if this is 923/931 install plugs in PTO shaft. One is supplied* From what has been previously posted on this site, PTO pressure lubrication is not needed on 923/931A2 install. It is not easy installing plug afterward.
Tip three: After making 'short bolt' from stud, MAKE SURE STUD IS STRAIGHT AND NOT WEDGED UP AGAINST CASTING IN AN ANGLE. If the stud is up against the housing...like tight and crooked, remove stud, grind in a taper, try again. If you don't do this ahead of time, you'll be under the truck with a Dremel grinding the taper- ...ask how I know. Once stud is clearanced and has room you should have roughly 3/8" of thread sticking out on the transmission side to thread in.
Tip four: Now that you have both studs in short bolt form, install long bolt with copper washer through housing. Directions state that one thick gasket is usually enough to gain proper clearance. I tried that and it wasn't enough and had to add more. I ended up with both thick gaskets and one thin gasket out of the four total supplied. YOUR SET UP MAY VARY.
Tip five: REMOVE SHIFTING LEVER. Remove shift plate now for ability to check gear lash later.
Tip six: Finagle the PTO up through between tranny and frame rail or from rear of trans. This will not be fun...but you should be able to find the right combination of angle(s) to get it up to near the PTO port. INSTALL your gasket onto the two short bolt studs and bottom long through bolt. Prep top bolt with copper washer for next step. You'll be under the truck and in the rear of the front fender opening enjoying yourself.
Tip seven: Get PTO into place and get top bolt started so it can help hold PTO in place while you start the studs. DO NOT TIGHTEN TOP BOLT! LEAVE ABOUT 1/4" GAP BECAUSE YOU NEED TO THREAD STUDS EVENLY AND BRING PTO TO TRANSMISSION EVENLY! Once top bolt has a few threads caught and comfortable holding PTO, start to thread in short bolt studs. Get one side caught by a couple threads then do the other. Remember, you need to evenly bring it to the transmission. The short bolt studs will be touching the four bolt caps of the shaft end plates which will allow you to get the open end of a 9/16" wrench in there to begin tightening them. You can hold the PTO against them to help them start. Make sure PTO to trans gap is even so they start squarely.
Tip eight: Tighten bottom long bolt, upper bolt and two short bolt studs. Check your gear play
TIP NINE: ON THE SHORT BOLT STUDS YOUR CREATED, NOW THAT THEY'RE TIGHT HOLDING PTO TO TRANSMISSION, TAKE A PUNCH AND HURT THE THREADS STICKING OUT PAST THE NUT ON THE PTO SIDE. Trust me- by doing this now, if you need to remove PTO (like I did for more shimming) nut won't back off leaving stud in transmission and you short on room to pull PTO off. Remember, short bolt, not stud anymore. You'll need to be able to remove the PTO to replace shift cover after you set your gear lash.
Tip ten: Remove PTO, add more gaskets for shimming if needed (and recheck lash), reinstall shifter plate, DO NOT INSTALL SHIFT LEVER YET. Reinstall PTO to transmission.
Tip eleven: Now install shift lever and cycle it back and fourth to make sure all's well. SLOWLY release pressure from jack and check shift lever to frame clearance. I was at zero lash from lever to frame so I put the jack back up, gave the tranny a nudge again, pulled shift lever, ground a 45* on it where it was hitting frame, then reinstalled it. I removed the jack and had a little clearance now. A little *should* be good as this engine and trans are mounted pretty well into the truck. Do what you're comfortable on clearance there.
Done on straight mechanical install. You'll still have linkage and wiring- Have fun. **DISCLAIMER- I'm dumb, so don't do what I do or say, do what you're comfortable with or follow directions.**
My PTO will be for nice meaty Commercial/Intertech pump I scored on eBay. I was going to frame mount pump but couldn't find my slip yoke section of driveshaft so I decided to mount it to the transmission...even though it's a divorced style pump. Below is the mount I made up to take advantage of some of the Allison's overbuilt meatiness. I had every intention of making another support bracket on an angle but the thing turned out to be rock solid so we're calling it a day. I'll make up a short driveshaft between the two and hope to soon be pushing oil! 
The NewStar PTO from C&C equipment (clintdigger) looks to be a nice unit. They're on eBay and the price is very attractive. I got a quote from a Parker/Chelsea dealer on a new 271 unit and was two grand. HA! My weekend was spent under the truck, but below are some tips that I hope will help some upcoming installs.
Tip one: Find a small jack to push against transmission from frame rail to gain a little more clearance. It won't be that much...but every little bit helps. Use your head, don't use a hydraulic jack and keep pumping until you split your transmission case as this isn't making a ton of room, it's gaining a little clearance temporarily.
Tip two: Don't install the studs into the transmission like the directions say or you will not get it on unless you drop trans or loosen a bunch of other stuff. Install studs into two lower side holes of PTO. Install copper washer, locking tab, then nut...and thread nut onto stud until you bottom out at the end of the threads. What you've just effectively done is made a short bolt. Also, if this is 923/931 install plugs in PTO shaft. One is supplied* From what has been previously posted on this site, PTO pressure lubrication is not needed on 923/931A2 install. It is not easy installing plug afterward.
Tip three: After making 'short bolt' from stud, MAKE SURE STUD IS STRAIGHT AND NOT WEDGED UP AGAINST CASTING IN AN ANGLE. If the stud is up against the housing...like tight and crooked, remove stud, grind in a taper, try again. If you don't do this ahead of time, you'll be under the truck with a Dremel grinding the taper- ...ask how I know.
Once stud is clearanced and has room you should have roughly 3/8" of thread sticking out on the transmission side to thread in. Tip four: Now that you have both studs in short bolt form, install long bolt with copper washer through housing. Directions state that one thick gasket is usually enough to gain proper clearance. I tried that and it wasn't enough and had to add more. I ended up with both thick gaskets and one thin gasket out of the four total supplied. YOUR SET UP MAY VARY.
Tip five: REMOVE SHIFTING LEVER. Remove shift plate now for ability to check gear lash later.
Tip six: Finagle the PTO up through between tranny and frame rail or from rear of trans. This will not be fun...but you should be able to find the right combination of angle(s) to get it up to near the PTO port. INSTALL your gasket onto the two short bolt studs and bottom long through bolt. Prep top bolt with copper washer for next step. You'll be under the truck and in the rear of the front fender opening enjoying yourself.
Tip seven: Get PTO into place and get top bolt started so it can help hold PTO in place while you start the studs. DO NOT TIGHTEN TOP BOLT! LEAVE ABOUT 1/4" GAP BECAUSE YOU NEED TO THREAD STUDS EVENLY AND BRING PTO TO TRANSMISSION EVENLY! Once top bolt has a few threads caught and comfortable holding PTO, start to thread in short bolt studs. Get one side caught by a couple threads then do the other. Remember, you need to evenly bring it to the transmission. The short bolt studs will be touching the four bolt caps of the shaft end plates which will allow you to get the open end of a 9/16" wrench in there to begin tightening them. You can hold the PTO against them to help them start. Make sure PTO to trans gap is even so they start squarely.
Tip eight: Tighten bottom long bolt, upper bolt and two short bolt studs. Check your gear play
TIP NINE: ON THE SHORT BOLT STUDS YOUR CREATED, NOW THAT THEY'RE TIGHT HOLDING PTO TO TRANSMISSION, TAKE A PUNCH AND HURT THE THREADS STICKING OUT PAST THE NUT ON THE PTO SIDE. Trust me- by doing this now, if you need to remove PTO (like I did for more shimming) nut won't back off leaving stud in transmission and you short on room to pull PTO off. Remember, short bolt, not stud anymore.
You'll need to be able to remove the PTO to replace shift cover after you set your gear lash.Tip ten: Remove PTO, add more gaskets for shimming if needed (and recheck lash), reinstall shifter plate, DO NOT INSTALL SHIFT LEVER YET. Reinstall PTO to transmission.
Tip eleven: Now install shift lever and cycle it back and fourth to make sure all's well. SLOWLY release pressure from jack and check shift lever to frame clearance. I was at zero lash from lever to frame so I put the jack back up, gave the tranny a nudge again, pulled shift lever, ground a 45* on it where it was hitting frame, then reinstalled it. I removed the jack and had a little clearance now. A little *should* be good as this engine and trans are mounted pretty well into the truck. Do what you're comfortable on clearance there.
Done on straight mechanical install. You'll still have linkage and wiring- Have fun.
**DISCLAIMER- I'm dumb, so don't do what I do or say, do what you're comfortable with or follow directions.**My PTO will be for nice meaty Commercial/Intertech pump I scored on eBay. I was going to frame mount pump but couldn't find my slip yoke section of driveshaft so I decided to mount it to the transmission...even though it's a divorced style pump. Below is the mount I made up to take advantage of some of the Allison's overbuilt meatiness. I had every intention of making another support bracket on an angle but the thing turned out to be rock solid so we're calling it a day. I'll make up a short driveshaft between the two and hope to soon be pushing oil!
