In article . com,
Andrew Duane wrote:

Driveways rarely crumble for no reason. It is likely there are
structural and/or drainage problems underneath that need to be found
and addressed.

You can get crumbling if the mix is too dry (ie, not enough oil
in it), or it was put on too thin. At any rate, the OP would not
want to overlay an existing crumbled driveway. They would want
to take your advice, remove the current blacktop, then double
check the base to make sure it is solid. If not, pull out some
material, and put in a foot or so of gravel base and pound it
down with car traffic for a few months.

-john-

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John A. Weeks III 952-432-2708
Newave Communications http://www.johnweeks.com
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