Hi
From Cisco doc:-
=============================================
EIGRP puts up to four routes of equal cost in the routing table, which the router then load-balances. The type of load balancing (per packet or per destination) depends on the type of switching being done in the router. EIGRP, however, can also load-balance over unequal cost links.
Note: Using max-paths, you can configure EIGRP to use up to six routes of equal cost.
Let us say there are four paths to a given destination, and the metrics for these paths are:
path 1: 1100
path 2: 1100
path 3: 2000
path 4: 4000
The router, by default, places traffic on both path 1 and 2. Using EIGRP, you can use the variance command to instruct the router to also place traffic on paths 3 and 4. The variance is a multiplier: traffic will be placed on any link that has a metric less than the best path multiplied by the variance. To load balance over paths 1, 2, and 3, use variance 2, because 1100 x 2 = 2200, which is greater than the metric through path 3. Similarly, to also add path 4, issue variance 4 under the router eigrp command. Refer to How Does Unequal Cost Path Load Balancing (Variance) Work in IGRP and EIGRP? for more information.
=============================================
So in your case you have to look at metric for the L3 etherchannel and the metric for the wireless link and then work out how many times you have multiply the metric for your L3 etherchannel to get to the metric for your wireless link.
Note that the wireless link must be a feasible successor to be used in unequal cost load-balancing so refer back to earlier posts for info on how to do this.
HTH
Jon
