Will work experience between 40 to 45 months consider bad for iims??

Not at all,It would be great advantage having that much experience which gives you 5 points and 10 points (out of 100) in some iims extra in selection process. Nearly 20% of people in iims are with experience around 3 years

The ideal amount of work experience is 24-36 months, in the sense that they get the most points during the selection process. work experience which is greater or lesser than that is still given some consideration but it is not as high as for those with 2-4 YoE.