P59 LoadLeash

ntroducing the only Engine Brake for ISB 5.9L Diesel Engines.
Quick & Controlled Braking For Heavy Duty Trucks Just Got Easier!

LoadLeash OEM Gasket Modification

Brad will walk you through the modification need to your OEM gasket for proper LoadLeash Engine Brake installation. This process is needed for late P-59 and P-67 LoadLeash Engine Brakes.

If I install the LoadLeash Engine Brake on my truck will it make that neat " Jake Brake" sound?

It will not. This style of the engine brake is what the industry calls a "weeper" engine brake, and it similar sounding to an exhaust brake.
When engaged, it holds an exhaust valve slightly cracked, slowing the engine by forcing the pistons to compress and suck air through a small opening, similar to the concept of blowing and sucking air through a narrow straw.
Compression release style engine brakes have an exhaust valve mechanism that it timed to the engine valve train to "pop" off the compression at a certain time which gives off the loud exhaust note, similar to when a pellet gun is compressed then fired.

Can I use the LoadLeash Engine Brake with an aftermarket turbocharger?

Yes, but you must also use an exhaust brake to create the back pressure needed to allow theLoadleash to perform at its maximum efficiency.

Can I install LoadLeash Engine Brake if I have ARP head studs?

Yes, you can. The Loadleash housing has provisions in place to allow the use of aftermarket head studs and nuts.
You can also use ARP custom aged head studs but must purchase the Pacbrake stud kit also made by ARP specially for this application. Part number P55127.

Can I use this LoadLeash Engine brake with my performance tuner?

Yes, your performance tuner will have no effect on the engine brake performance.

My truck has had an emissions delete, can I still install this LoadLeash Engine Brake?

As long as an exhaust brake or VGT brake is still present, an emissions delete will have no effect on the engine brake performance.

How much braking power will increase over the factory exhaust brake with the use of LoadLeash Engine Brake?

Pacbrake’s LoadLeash, used in tandem with the VGT exhaust braking feature, will result in a 40% increase in retarding HP when measured at the rear wheels (assuming 60 HP of drivetrain friction).

LoadLeash + VGT = 360RHP | VGT Only = 210RHP

Do I always have to turn on the Exhaust brake button to make this brake work properly?

Yes, ideally you should always run the exhaust brake in combination with the LoadLeash for it to perform at its peak.
Using the LoadLeash without the exhaust brake on will not harm the engine but it will not brake as hard as with the exhaust brake activated.

Do the municipal street signs that state "the use of engine brakes are strictly prohibited in urban areas" apply to my LoadLeash Engine Brake?

No, the LoadLeash, although an engine brake, gives off very little noise or exhaust note.

I don't have an Exhaust Brake, can I still use a LoadLeash Engine Brake?

Yes, you can but it will not perform to its maximum braking performance.

Warranty Registration

Register your product for warranty HERE.