June Tech Tip – Liftgates

A diesel vehicle

Monthly Maintenance Tips From Our Service Department

Having a liftgate issue is one of the surest ways to take a good day and make it bad. On top of the frustrations there is always the safety concerns.  Hopefully, I can help make sure your good day stay 95% good at least.

When looked at as a total package the liftgate is a pretty basic system. Electrical power runs the motor/pump to give you hydraulic force which, using a hydraulic cylinder, lifts the platform. When you want to lower the platform, electrical power is applied to a solenoid that opens up and allows the hydraulic fluid to drain back into the reservoir (gravity fall system). While the system is simple, it can have the biggest impact on your day short of the engine not starting.

The most common problem, by far, I encounter with these liftgates is a blown fuse to the solenoid that runs the motor. If this fuse is blown, the liftgate just won’t operate.  This often happens due to wire corrosion or if someone tries to “jump” the pins and touches a ground. If this happens, pull of the rear valance panel (the panel with your taillights… 4 ea. – 10mm bolts (in red), lower the panel and replace the fuse (20A, located directly behind where your license plate would be).

Another item to check is the 150A circuit breaker in your main electrical box (below the inverter). 

Be sure to keep the maintenance up on these units also. Periodically check the fluid level (use Dexron III), keep the tracks clean and lubed (use 10W or 20W oil), give all the hinge points a good squirt of WD40, inspect wiring and connectors regularly, and be nice to the remote controller! Refer to your owner’s manual for all your specs. If you don’t have a manual let me know and I’ll email one to you.

Last, but not least… DO NOT drive your truck unless the liftgate is upright and fully seated in the cradle points with safety pins installed! It’s illegal in most, if not all, states and will almost certainly cause damage to the liftgate and the box where it is mounted. Driving with it down will void any warranties with the OEM (Thieman Liftgates). If your gate gets stuck down call us (303.301.7550). or call Thieman (800.254.5210) for help.