Engine/Transmission (1994 - 1998) PTO install on a nv4500

[Jff24Gordn]

I might be putting a PTo on my 5 speed. Does anybody know the specs on the gear that it runs off of. like tooth spacing, angle of the tooth face, the amount of twist to the teeth, any any other info on matching a pto gear to the transmission gear.

 

[illflem]

PTOs are pretty basic, there are really only a few choices, any supplier will match you right up. Only things you really need to know are what side of the trans you want it on, which direction it rotates, gear ratio you want for rpms and the method of engagement (cable, electric or vacuum).

 

[T. Baker]

I was just wondering the same thing. Are pto gears standerdized as far as pitch etc. ? I have seen SAE bolt patern spacer blocks before wich I think help mate up pto's to trannys with different dieameter gears as long as the pitch is the same. All of the ones I have seen use straight cut gears.

 

[Whitmore]

I learned the hard way

When you do get your PTO make sure you just dont bolt it up, you have to treat it like a ring and pinnion, use of shim stock could be paramount to the longivity of the unit and your transfer case.



Also you may have an option, look under your truck , you may have a PTO outlet on the transmission and if you have a 241HD than you will have a PTO outlet on it, I would prefer using the transfercase outlet... ... ... ... ..... for what ever its worth,



cheers, Kevin

 

[illflem]

Problem with a transfer case pto is that pto speed will vary depending which gear your transmission is in. It will also be able to spin backwards with transmission in R, which can be disastrous for some pto driven devices. You also have to leave the transmission in gear and the transfer case in N to operate the pto while stationary. Too many potential mistakes to make. Transmission mounted ptos always spin the same direction no matter which gear (or N) you're in and pto speed is determined only by engine rpm.

Transfer case ptos are usually reserved for applications where the pto speed needs to match ground speed such as a trailer with a drive axle.



As Kevin said shiming the pto unit from the transmission is very important in order to get the proper gear lash or you'll tear up both the pto unit and transmission. Most ptos come with several shims to do the job correctly.

 

[Jff24Gordn]

I know it must be shimmed right, or I'm gonna toast the transmission. I was just wanting the gear specs to double check the parts that the parts guy at the semi supply store tells me should work. I dont think that every transmission has the exact same gear in the exact same place to drive the unit.