adding pto

[Gerry]

I am adding a winch to my truck and was wondering where I can get the studs that hold the pto to the tranny or do people usually just use bolts?
Thanks,

[Master Yota]

The PTO on my Cdn. M37 was simply bolted on; however it had a rebuild tag dating back to 1972. It may have had studs originally that had been removed.

I imagine that bolts would be just fine.

[MSeriesRebuild]

You can get studs at any local auto parts store , NAPA, CarQuest, etc. Usually they are in the Dorman Products line. Bolts will work, but you will find the installation is much easier if studs are used. More than likely you will have to take it off and on several times to get the shim pack correct, bolts get really aggrevating.

[Master Yota]

You can get studs at any local auto parts store , NAPA, CarQuest, etc. Usually they are in the Dorman Products line. Bolts will work, but you will find the installation is much easier if studs are used. More than likely you will have to take it off and on several times to get the shim pack correct, bolts get really aggrevating.

That makes excellent sense. The bolts on my unit were a PIA...

[Gerry]

Thanks,

[MSeriesRebuild]

You can get studs at any local auto parts store , NAPA, CarQuest, etc. Usually they are in the Dorman Products line. Bolts will work, but you will find the installation is much easier if studs are used. More than likely you will have to take it off and on several times to get the shim pack correct, bolts get really aggrevating.

That makes excellent sense. The bolts on my unit were a PIA...

Something else I failed to mention, whether using studs or bolts, pay close attention to any threads that protrude toward the inside of the case. Be sure that none interfere with rotating gears inside the case. It's best to get studs that are exact length so they are flush with the interior case wall.

[Gerry]

Thanks Charles.
I do have one stud that came with the pto so I can get an exact stud

[MSeriesRebuild]

Thanks Charles.
I do have one stud that came with the pto so I can get an exact stud

Be sure and notice that 1 stud is longer than the other 5, because of the PTO flange thickness.

[Gerry]

Charles,
Thanks a lot for that I wouldnt have noticed!!!!!

[cuz]

There are 5 studs 3/8-16NC (9/16) x 3/8-24NF-2 (5/8) x 1 9/16 (3/32 drilled)
There is one stud 3/8-16NC (9/16) x 3/8-24NF (5/8) x 2 3/8

for a total of 6. Used with 6 lock washers and plain nuts with the 5 short studs lockwired.

[Gerry]

Thanks Wes,
Is there a hole to wire them or how do you do that?

[MSeriesRebuild]

Thanks Wes,
Is there a hole to wire them or how do you do that?

Early trucks were security wired, later trucks did not have that. If you do a correct installation, it will not be necessary.

[cuz]

The process of lock wiring or safety wiring has been around for a full century now.

As threaded fasteners with improved locking characteristics were developed the need for this lock wiring slowly faded out of use. The process is still used in Aircraft work and vehicle racing fields. As Charles said above it is not necessary if you are using quality lock washers and the B1's came with the lock wire but the drilled studs were still used. The old M series and earlier mechanics would still lock wire them in the field. It is up to you and what level of accuracy you are looking for in your M truck's restoration.

There are several methods but the two most common are a continuous loop or paired and twisted.

Twisted pairing

Continuous loop or single strand.

http://www.whizwheels.com/Tips/safetywiring.html