8070 pto clutch

Should be the same if not use 8070 plates because you don't change the clutch to make it a 540. I would also check the pressure. Clutch may not hold the 8070 with 540 speed. MACK

There are some things that never fail.....the PTO clutch on a 7000 and 8000 series is one of those things. In 35 plus years I have repaired TWO pto clutches.....the first in 1982 on a 7020 under warranty (had a bad casting causing low clutch pressure) and in 1990 on an 8030 running a hay tub grinder that was plugged with a wet bale of hay. After killing the engine, it took 8 full throttle attempts to unplug the grinder and by then there was smoke coming from the fill cap on the rear end. Those are the only two I've ever seen fail. On the clutch cover top there are two pipe plugs....one for brake pressure and one for clutch pressure.....they should be the same and around 280 to 350 psi at full throttle.

I'll defer to the mechanics that have worked on the PTO, but I believe the clutch is "upstream" of the gear reduction.  If so, the torque on the clutch is the same for either 1000 or 540 PTO's.  The torque at the output, of course, is much higher with the 540 PTO due to the greater gear reduction.

Using the full engine power of an 8070 on a 540 PTO implement could lead to lots of broken pieces and possible serious injury to any bystanders.

427435 wrote: Using the full engine power of an 8070 on a 540 PTO implement could lead to lots of broken pieces and possible serious injury to any bystanders.

Doesn't the PD always start in low, thus the low side is the feathering side as well, thus requring extra plates to maintain durability and reliability even if they both carry the same maximum torque? 

MACK wrote: 427435- The PTO clutch still sets between power sorce and load. Then why does the PD(which sets between power sorce and load) always have more plates on low side than it does on HI side?   MACK

While inching is something that enters into a clutch design, the most important thing is the torque the clutch has to transmit.  A clutch that is the first thing in the drivetrain behind the engine only has to handle the max engine torque.  If you put a 2:1 gear reduction between the engine and clutch, the clutch will need to handle twice the torque-----------and gets bigger (diameter or pressure or number of plates).

Jordan(OH) wrote: Never made sense to me why the 8070 had large 1000 only PTO.  That would be like Ford welding a 2 5/16 ball to a F350 and telling customers "you can't pull a small trailer with this."  Remember the saying "you can do a small job with a big tractor but you can't do a big job with a small tractor"?

So if there would have been a factory 540 PTO on the 8070 and someone tried to use full power on a 540 implement, breaking the shaft off and someone got injured, who do you think gets sued???

But, at that time in history, tractors over 165 pto  HP were required to have the large 1 3/4" shaft by law.....and no 540 pto even offered.