The HPI Wheely King is robust and a proven 4×4 electric monster truck. Its simple design and its scale look have charmed many RC enthusiasts like me. From the factory, the Wheely King comes with front and rear differentials. Like for any differentials, the power is transferred to the wheel that has less traction. If you want more traction from your Wheely King, HPI has an affordable(less than 7$us) differential lock option (PN: 88073) that will dramatically increase the traction and off-road capabilities of your Wheely King. I have installed and tested one on my Wheely King. Clear instructions are included with the diff lockers. They are well detailed, in fact they seem to be too well detailed. Keep on reading to know how I’ve installed the diff lockers on my Wheely King.
Remove the differentials:
The first thing is to remove the differential. You just need a #1 and #2 Philips screw drivers for the whole upgrade process. I recommend you to do one diff at a time. This will minimize the chances of mixing parts. Once the wheels and the body are removed, flip the truck over on its lid and remove the diff from the truck by removing the clamp where the shock and the suspension link are attached. There are only two Philips screws to remove on each side of the differential. Next you need to remove the steering rod (for the front diff only) and the remaining suspension arm in the center of the diff.
Once the differential is removed, you must remove the left and right hub carriers. They are held in place by two Philips screws on each side. Once the screws are removed, slide the hub carriers out slowly.
Next, you must open the differential case to have access to the diff gears. Remove the four Philips screws located in the center of the diff case. Slowly open the diff case and remove the diff from the case.
To open the diff, remove the four Philips screws holding the 38T bevel gear to the diff case. A #1 Philips screw driver is required because these screws are smaller. Once the diff is opened, remove the two 13 tooth and the two 10 tooth bevel gears from the diff case. They will be replaced by the diff locker. Remove the shims (very thin washers) from the bevel gears and install them on the diff locker.
Now, you must insert the diff locker into the diff case. Play close attention to the position of the diff locker, the side with the lower flange in the middle goes into the diff case. Now reassemble the diff. Note that I didn’t clean the diff case before installing the diff lockers. I preferred to let the stock grease inside the diff case and I have applied additional grease where the axles enter the diff locker.
It’s done! Now you have to rebuild the differential and reinstall them on the Wheely King. It took me about 45 minutes to install both diff lockers.
By installing the differential lockers, I’ve dramatically increased the overall off-road potential and traction of my Wheely King. The truck has way more off-road capabilities like it never had before. I have tested the truck before and after I’ve installed the lockers on a little hill in my backyard. The difference is like night and day. The only downside of locking the diffs is the turning radius that has increased. Otherwise, go and lock your diffs. It is a well spent 7$!
For more informatio, visit www.hpiracing.com