Transferring Power Take-Offs To New Trucks

Planning to transfer Power Take-Offs (PTO) from old trucks to new?
Check before you spec that new transmission.

“Make sure you check the “Percent of Engine Speed” transmission specification,” said Jay Riley, Roadranger® national accounts service manager. “And that the final gear ratio is the same as the transmission you’re replacing.”
 
This is because head set gear ratios may be different between similar models. This means one model might produce 94% of engine speed and a newer model may only produce 79% of engine speed,” Riley continues. “The slower speed means the driver needs to increase engine RPM’s, and burn more fuel, for the PTO output to operate at the same speed as before."
 
If the PTO is driving a blower, PTO speed is critical when loading and unloading.
 
“Some fleet customers have contracts that specify strict load and unload time windows,” said Riley. “If they go over their time, they’re financially penalized.”
 
Driveline Yoke Clearance
 
Another spec'ing consideration is driveline yoke clearance. Riley explains, “we’ve seen an example where a driveline yoke diameter was interfering with the Thrushaft® PTO housing. There are several driveline options available to avoid this. In addition, there are new Thrushaft PTO’s that are more compact and have faster ratios to offset the slower transmission percent of engine speeds.”
 
Primary PTO Types
 
6-bolt: Parker Hannifin Corporation8-bolt: Parker Hannifin Corporationthrushaft: Parker Hannifin Corporation
Six-BoltEight-BoltThrushaft
 
“A Thrushaft PTO is more reliable than the traditional 6- and 8-bolt styles, which are prone to loosening, leakage and potentially shortening transmission life,” said Riley. “Unlike the 6- and 8-bolt, you can only select a Thrushaft PTO option when you order a new truck.”
 
Thrushaft PTO on TransmissionSo, if you’re spec’ing new trucks and plan to transfer PTO’s to them, make sure there’s enough engine speed and driveline yoke clearance (Thrushaft) for a smooth transition and help protect your PTO investment. You will also want to confirm that the PTO models you are planning to transfer are compatible with the new transmission model because they are not all the same anymore. Contact your PTO manufacturer representative for the latest information.