Chealsea PTO?

94f450sd

Supporting Member
Supporting Member
Joined
Oct 12, 2005
Posts
6,617
Reaction score
55
Location
somewhere,ma
All ptos use the same bolt pattern.there are a couple different gears for the ZFs.been there done it.if the gear is wrong,just go buy the gear you need for your tranny or tcase and swap it.
 

lotzagoodstuff

Supporting Member
Supporting Member
Joined
May 19, 2007
Posts
2,726
Reaction score
668
Location
Carmel, IN
All ptos use the same bolt pattern.there are a couple different gears for the ZFs.been there done it.if the gear is wrong,just go buy the gear you need for your tranny or tcase and swap it.

All PTOs are not the same bolt pattern. Eaton RoadRangers actually have different bolt patterns on the bottom (8 bolt) and the side(6 bolt), so you have your choice of position, but the same unit won't fit both openings on the same transmission.

You could say that "all 6 bolt PTOs use the same bolt pattern", and you'd be correct, but remember the gear depth and pitch angle matter, especially when we are talking about something like a 410 which hasn't been manufactured for 20 years. If you bought a brand new Chelsea 442, you have a choice of an X mount (standard) or Z mount (deep mount), which take different input gears to mate to your transmission.
 

94f450sd

Supporting Member
Supporting Member
Joined
Oct 12, 2005
Posts
6,617
Reaction score
55
Location
somewhere,ma
We arent dealing with road rangers here,we are dealing with pickups.whens the last time you seen a road ranger in a ford pickup?ive never seen one unless it was a custom build.i can take the pto off our chevy 6500 2car carrier with an eatin 6 speed and bolt it to your puny little ZF,the gear will be wrong but i can buy the one i need.doesnt matter how old the pto is,they still sell the gears and rebuild kits for them.
 

jaluhn83

Full Access Member
Joined
May 19, 2012
Posts
1,597
Reaction score
48
Location
Upper Marlboro, MD
My understanding is that the 6 bolt PTO opening and bolt size is standard, as it the overall design of the housing, etc. (within a particular series/manufacturer) However, the gear size, number of teeth, pressure angle, etc are all specific to certain transmissions, and even ratios. A ZF5-S42 & S47 diesel PTO are different for example. It may be possible to make one work if the difference is only in gear spacing (that is, you need to add a spacer between PTO & trans), but that assumes that everything else is going to work right. The PTO internal gearing may also be speced differently for a certain output speed/direction, which is of course important to consider. About the only way to really tell for sure is to decipher the code number, which requires the proper document, or put it on and pray.....

That being said, the gear teeth on that one look in decent shape - since it's a sliding gear, misuse or lots of use will typically show as wear on the gear tips like you'd see on a starter pinion.
 

79jasper

Chickenhawk
Joined
Oct 13, 2012
Posts
17,367
Reaction score
1,930
Location
Collinsville, Oklahoma
I'll just say, on a zf5 with the pto, gear lash/preload whatever you wanna call it is excruciatingly important. Ask me how I know. Lol ;)

Sent from my SM-T537R4 using Tapatalk
 

lotzagoodstuff

Supporting Member
Supporting Member
Joined
May 19, 2007
Posts
2,726
Reaction score
668
Location
Carmel, IN
My understanding is that the 6 bolt PTO opening and bolt size is standard, as it the overall design of the housing, etc. (within a particular series/manufacturer) However, the gear size, number of teeth, pressure angle, etc are all specific to certain transmissions, and even ratios. A ZF5-S42 & S47 diesel PTO are different for example. It may be possible to make one work if the difference is only in gear spacing (that is, you need to add a spacer between PTO & trans), but that assumes that everything else is going to work right. The PTO internal gearing may also be speced differently for a certain output speed/direction, which is of course important to consider. About the only way to really tell for sure is to decipher the code number, which requires the proper document, or put it on and pray.....

That being said, the gear teeth on that one look in decent shape - since it's a sliding gear, misuse or lots of use will typically show as wear on the gear tips like you'd see on a starter pinion.

That's a pretty good explanation, the only thing you left out was the arrangement, which is defined as the different configurations you can reconfigure the same housing to account for whether you want it on the driver's or passenger side, or whether you want it output centerline high or low.

Again, if you want to spec a brand new Chelsea PTO, all this is available and relatively easy, but when you get to a 410 that hasn't been made for over 20 years, the availability of the parts to reconfigure gets somewhat sketchy.

79jasper, Chelsea went away from the sliding input gear on everything as the thought is that if the operator does a bad thing and tries to engage the PTO while things are still turning, he (or she) will only damage the internal gear on the PTO, as opposed to the output gear on the transmission. PTO designers always want to break parts in the PTO, not the transmission. For instance, on an Allison, Chelsea will only rate the PTO to that maximum torque that the specific Allison can take. The 890 Chelsea PTO is limited to 670 foot lbs, but in actuality the 890 can take more torque itself but it will result in the Allison being damaged.

I'm going to step out of this thread as there are folks on here who've explained to me that they have far more expertise on this subject than me :rolleyes::angel:
 

Latest posts

Forum statistics

Threads
91,217
Posts
1,128,471
Members
24,043
Latest member
tottripp

Members online

Top