NEWS | Feb. 11, 2020

Stryker: Ramp PM Keeps Vehicle Mission Ready


Following these tips will help keep your Stryker’s ramp working and make sure you and your fellow Soldiers stay safe during operations:
● A slow or balky ramp can be a sign of hydraulic problems. Open the rear service hatch and take a close look at the vertical tube at the back. If the fluid is 1/4 to 1/2 full in the tube, the hydraulic level is OK.
   
● If the hydraulic level is too high (above 1/2 full), the hydraulic seals will blow. Too low (below 1/4 full) and the ramp might not raise and lower. The annunciator panel should flash and sound if the hydraulic fluid drops below 6 1/2 gallons. 
● Be careful not to exceed the load capacity for the ramp and ramp door. The ramp chains may stretch or break and you can ruin the hydraulics. The ramp door seal or hinges could also be damaged.
        
The ramp’s load capacity with slat armor is 1,000 pounds and the door’s load capacity is 500 pounds.
        
Always raise or lower the ramp completely.  And don’t lower the ramp partially to give Soldiers a seat or to carry equipment, especially when slat armor is installed.
        
Leaving the ramp partially opened for a while can stretch the chains. Extra weight from you and your fellow crewmen just makes it worse.
        
And make sure you open and close the ramp smoothly. Flipping the ramp switch up and down will make the ramp jump and jerk as it moves. That puts extra strain on the hydraulic rams and can blow the seals. 
    
    
Don't flip ramp switch up and down repeatedly

● Remove any water buildup under the floor plates.  Then have your mechanic give the ramp chains a light coat of GAA semiannually to prevent rust.
        
Sometimes only the portion of the chain that’s visible when the ramp is down gets lubed. There’s quite a bit more wrapped around the pulleys and hidden beneath the floor plates. So make sure your mechanic lubes the entire chain. 
 
         Be sure to lube unexposed part of chain

● Give the ramp chain pulleys a few shots of GAA, too. There’s a lube point at the top and bottom of both housings holding the pulleys. It’s easy to miss the bottom ones. 
 
         Lube top and bottom pulleys of each chain

Tap the horn twice and then wait a few seconds before raising or lowering the ramp. That gives others a warning and enough time to get out of the way.
● Before closing the ramp, make sure the vehicle has enough air pressure built up. It needs to be at least 85 psi. If the air pressure’s low, the ramp locks may not engage completely. Check to make sure the RAMP OPEN LED goes out.
        
If you’re closing the ramp from the squad compartment, make sure the cam locks rotate all the way to the closed position.
● A Stryker facing downhill on a slope of more than 15 degrees may need a push from inside the vehicle to help the ramp start opening, especially if slat armor is installed.
    
● When the vehicle is parked facing uphill, be very careful when opening the ramp’s personnel door, especially if slat armor is installed.
        
The door can swing open suddenly when the latch is released.  That means Soldiers can be crushed between the door and the slat armor that covers the right fuel tank cap!
● The ramp won’t lower completely if the tow pintle is installed. It juts out enough for the ramp to hit and bend the pintle shaft.
        
Until it’s actually needed, remove and stow the pintle and replace it with the pintle plug, NSN 5340-20-001-0203. That keeps dirt and moisture out of the vehicle. You’ll also need an O-ring, NSN 5331-00-585-1068, and a lock pin, NSN 5315-01-328-5286, to install the plug properly. Note that this pintle information is for flat-bottomed Strykers, not double V-hulled (DVH) vehicles. These parts won’t fit DVH Strykers.
Follow the tips above and your Stryker’s ramp will be ready at all times!