Thanks for all the tips .....

Rabbcon:

I entered the tare you stated and it did help, my setting were quite different, it was set on:

med: 15:1
large: 10:1



Dr Byte:

It pulls the data from the UPS website directly, using the package weight, and the customer's zip code and your zip code (from Admin->Configuration->Shipping/Packaging).
It also adds additional weight to the quote if you've got the tare settings set to do so.

Does your worldship quote differently than if you went online to the UPS website and requested a quote from their shipping rates page, using the same criteria?
Thanks, I didn't know where it pulled the rates from. The worldship quote is the same as the UPS online quote, and by checking it on UPS online, I was able to determine where the extra cost is coming from...but I'm not quite sure how to fix this.

Here is the problem: I just found out that all domestic UPS next day air packages are based off of dimensional weight, instead of actual weight, so for example, the order that cost $123.00 to ship and the shopping cart charged the customer $90.00 was because UPS charged for dimensional weight of 24lbs. instead of the shopping cart actual weight of 10lbs. (the box isn't classified as oversized or anything by UPS)

So....how can I set the zen cart to know that only the UPS next day air packages are going to be off of dimensional weight, and I guess I will need to determine which box it will ship in before it is ordered, so I will know what to charge for the dimensional weight?

Any help is greatly appreciated