The pivoting dump chute has become quite popular as a means by which the NFPA 1901 dump requirements can be met and a means by which to retrofit older rear-dumping tankers so that they can also side dump. Most of the time there is no issue with the pivoting dump chutes...they work pretty well and meet the NFPA flow requirement. In our travels we get to see a good number of tankers and on occasions we find a rear pivoting dump chute that does not clear the top of a deployed dump tank. While this is not a "deal breaker" it does slow down dumping operations because a human being has to try and lift up the chute so that it clears the top of the dump tank so that water can be dumped. Quite often, we see this with rear-dumping tankers that are retrofitted with the pivoting dump. So...our words of caution (or wisdom, however you care to look at it) advise you to carefully measure the height of your existing dump chute to ensure that a pivoting dump chute retrofit will clear the top of your dump tanks.