To refill your RC truck shocks the first step is to remove the shock with an alarm key located at the bottom of the shock. The next step is to pull the spring back and remove the lower joint and spring then remove the cap screw and be careful, their might be some oil still in there. Fill all the way up to the top if you want stiffer shocks and pump the shocks a few times to eliminate bubbles in the oil. Then reassemble and check to make sure it meets your needs and you are done.
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