PTO puzzlement

[Tinbasherdan]

One more for the random wondering pile…..

I’ve a pair of zf s5-42 boxes, one old one with a 4.65 1st and one with the later 5.72 ratio 1st.

I have a pto and hydraulic pump setup that came with the 4.65 box, but nothing for the 5.72, howeverrrrrrrr…….

Upon googling it I found at least one company selling the same side mount pto as “dual ratio” to fit to either box. I can’t really work out how that’s possible unless the layshaft it takes power off is the same on both? Boggling my mind!

 

[sako243]

I'd have thought most lorry PTOs (without really knowing) would be driven off the main shaft such that they're only dependent on engine speed.

If it was driven off something else it means you need a second gearbox like the LT230 such that you can disengage the drive shafts from the engine if you wanted to use it stationary.

 

[8ob]

Always off the layshft Ed because its constant mesh, mainshaft in neutral is exactly that. Truck PTO`s are all over the place, some boxes run one straight cut gear on the layshaft just for the PTO, some mesh onto one of the gears. A good chance the one @Tinbasherdan is on about has the same diameter spur gear on the layshaft irrespective of box ratio.Some of the spicer boxes were like that.

Bob

 

[Tinbasherdan]

Always off the layshft Ed because its constant mesh, mainshaft in neutral is exactly that. Truck PTO`s are all over the place, some boxes run one straight cut gear on the layshaft just for the PTO, some mesh onto one of the gears. A good chance the one @Tinbasherdan is on about has the same diameter spur gear on the layshaft irrespective of box ratio.Some of the spicer boxes were like that.

Bob

Cheers Bob, I suppose the best way to find out is to offer it up really and see if it fits!

 

[sako243]

You mean you haven't already done that?!

 

[Tinbasherdan]

You mean you haven't already done that?!

Not on the new box! Haven’t got that far, I was just wondering if it would/wouldn’t. New one is literally brand new so didn’t want to much it!