what is a2.5l merc preload lower unit?

[alxb2003]

what is a preload lower? can it be used on any 2.5? thanks

[transomstand]

A preload could be used, although considered less desirable, because they are a bit weaker than non preloads. 2.5's never came with them, they had been discontinued before the 2.5 was introduced.

[alxb2003]

thanks!