Equity type accounts

[gnucash at madsteer.com]

Can someone explain the equity type accounts?  The only account in there
by default is "opening balances".  While this might accurately reflect my
equity when I first built my current gnucash file and propigated the
various accounts with opening balances, it really isn't accurate at all
anymore.

For example, I recently sold my truck and bought a van.  So when I built
an asset account to reflect the value of my truck, there was an opening
balance that is reflected in equity.  Now, I decreased that account to 0,
by making a decrease to the Expense:Adjustement account.  Then I opened a
new account for the van.  Equity noew reflects both the value of my truck
and my van, due to the opening balances.

What am I missing?  Should I have some other accounts of type equity?  Am
I making things confusing by having seperate asset accounts for each of my
vehicles?

Thanks for the help.