I am doing my B.E mechanical engineering. It is my final year. I wish to apply MBA in USA. I would have a good exposure there. My undergraduate scores are very low. if my gmat score is 600, is it enough to get into a good university.my budjet is only 40,000 USD. and also I dont have any idea of what specialization in MBA i have to choose. Can anyone help me regarding this?

All reputable MBA programs will require that you have work experience. You might want to look at pre-experience master in management programs instead. The best ones, like Kellogg's MSMS program and MIT Sloan's MMS program, maybe out of reach for you in terms of cost, but maybe there's something at a lower tier school which might be more affordable.

Pradeep,

you have too many constraints for a "good university"
1) Academics: Low GMAT, bad undergrad
2) Financial: $40,000 for tuition + cost of living. [Cost of living for a 2 year program alone would be $24,000. $1,000/mo x 12(months) x 2 (years) ]

Why would a good university take you? you neither have GMAT to boost their rankings or money to pay their fees?

Either retake the GMAT to improve it, or work for several years to save money towards your MBA (and/or find other sources of funding)

OR

Within your constraints, find a MBA program - but it may not pass your definition of "good". Look at Williamette University - Atkinson.

Ayon thank you for your opinion. My budjet 40000usd is only for tution fees. and i will take another 5000usd for my expenditure. I think that i will manage by part-time job. Can suggest me some universities where i could get placed?

[Edited by pradeep7858 on Oct 06, 2016]

Try Shortcut to find the best US MBA www.find-mba.com/board/36065

@Pradeep,
It's a tight rope. $5,000 /year for your expenses is ~$420 per month. I did my MBA from a small town and my monthly rent was $450. This included rent+utilities only. I shared a 2 bedroom flat with 3 people. You won't have it cheaper than this- my classmates were paying $650 to $1200 per month (per person) depending on lifestyle.

You'll need to consider costs as well here is a sample ballpark tentative split (Conservative estimate)
Monthly:
Rent $450
Mobile $50
Food $300 [Subway sandwiches $6 foot long for 30 days + bread/eggs/fruits for breakfast]

One Time:
Airfare $1000
Laptop $900
Books/Course pack: $1000
Mobile $400 (Deposit in lieu of Social Security Number)

What do you mean by getting placed? Getting an admit or finding a job? If it's the former than follow the link Duncan suggested. If it's latter then probably get some reality check - US doesn't "place" students. Students find the job on their own.

You cannot do a part-time job off campus. This would be a violation of Student Visa. You can do a part-time job on campus not exceeding 20 hours/week. This is easier said than done. Most universities don't allow students to work in first year since the MBA 1st year is demanding. Even if you can find part time on-campus the pay is minimal $7.5/hour to $10/hour in a small town $15/hour in big cities. This is of course pretax.