Change of insulin dosage when switching to the pump?

Okay, I cannot be the only one who had these issues when moving to the pump....Prior to starting my Tandem T-slim i was taking 40 units of insulin every evening and between 75-100 units of fast acting through out the day *note i am very resistant to insulin as a Type 1 due to my PCOS and Cushings, which both typically lead to severe insulin resistance and Type 2 diabetes. I am also on Metformin 2,000mg a day one in the AM and PM.
However i started the pump, and the conversions of the 40 units of fast acting did NOTHING for my basal, it increased so drastically, i was taking 269 units a day JUST in i was taking in over 300 units a day, having to change the cartridge twice a day as well... I gave it a week, hoping it would lower and even itself out, but after 8 days, i decided to go back to my Lantus, which has now had to be increased to 50-55 units if i am bolusing from my pump, but if i take my mealtime boluses with a syringe then 40 units of Lantus is great, i have been experimenting. I had another training session with my CDE rep of the pump, and i am doing everything right, so she and i are both baffled...My question is has anyone else had this issue? I don't want to be taking 10 units an hour basal, if i can take an injection of 40 and keep my basal under control. Any advice or info is greatly appreciated!!!

What insulin in the pump?

I know of a least one member here that cannot use one particular brand as it does not work for him, at all. I don't recall which brand.

Perhaps you should talk to you doctor about switching brands?

I have tried Apidra, Humalog, and Novalog which all 3 gave me the same effect

Have you tried different infusion sets? When I first started on the pump I was having similar issues with weird absorption through the pump and it turned out the plastic cannula was causing an allergic reaction which was hindering my absorption. I changed to steel sets and now all is (more or less) well with the world.

I agree with Amy. Seems like you could have a problem with the way the insulin is absorbed. Could be either the site or the infusion set. I would also recommend steel cannulas. I use them myself an my absorption is way better than when using teflon infusion sets. Try to get your hands on different infusion sets and try them out.