2nd gear may not be able to be achieved in a bumpy high grass situation. When it is bump the truck cannot achieve the speeds needed to shift into 2nd gear. But it may also be that when it is being thrown around from the bumps that the engine is able to rev freely and will then shift earlier because it will think the speed is higher because of the free moving tires. Which means that you may not be able to tell by the sound of the engine. But if it is not shifting yes the engine will rev kinda high if your going as fast as you say your are. But i would not be worried about the truck shifting into 2nd when driving in the yard. If the truck thinks it should shift then it will and I wouldnt be concerned but then again thats just me.

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