Thanks AO Custom. I too just ordered a set from Amazon.ca, they will be here tonight! For those interested, the model for our wheel size is the AutoSock HP 697.I've experienced the same issue, it seems my sister's mini van does better on snow packed inclines. I have not weighed the front end of my 159 but I feel like it's very light on the front end and this is possibly contributing to lack of traction. To over come the traction issues I've experienced, I purchased tire chains and Autosocks. I recently used the Autosocks to drive up a snowpacked road and they worked awesome - super easy to put on and take off.
Link to amazon is AutoSock 697 Size-697 Tire Chain Alternative, Snow Chains - Amazon Canada