Should be easy - trying to setup two internal networks to use two different WAN links. I am using a SonicWall NSA 4500, utilizing 4 of the interfaces as follows:
X0 - Primary LAN - 192.168.10.1 /25
X1 - Primary WAB - b.b.b.b. Gateway: b.b.b.a
X2 - Secondary WAN - c.c.c.c gateway c.c.c.b
X3 - Secondary LAN - 10.10.254.1/24
So, I have it setup that the b.b.b.a is my default gateway. I have a laptop with a static IP 10.10.254.10/24 plugged into X3. I can ping this from any device on the X0 subnet or anywhere else.
So I have created a rule where:
Source: X4 Subnet
Pings timeout. If I remove the rule, I get out just fine, but am using the wrong outbound interface.