This question comes up almost daily and we need a sticky.
If you are late on your student loan, or you default, you cannot expect goodwill from your lenders as they are required (by law...see below) to report factually and accurately. Student loans are a complely different animal to credit card and other consumer debt so don't expect the same rules to apply.
If you default or your loan is sold expect those lates to remain for 7 years. If you consolidate, the lender will not remove the lates. If you rehab, the original lender who default you is under no obligation to delete or update your tradelines when you complete the rehab program.
http://www.ed.gov/policy/highered/leg/hea98/HR6.pdfQUOTE
Notwithstanding paragraphs (4) and (6) (FOOTNOTE 1) of subsection (a) of section 605 of the Fair Credit Reporting Act (15 U.S.C. 1681c(a)(4), (a)(6)), a consumer reporting agency may make a report containing information received from the Secretary or a guaranty agency, eligible lender, or subsequent holder regarding the status of a borrower's defaulted account on a loan guaranteed under this part until -
(1) 7 years from the date on which the Secretary or the agency
paid a claim to the holder on the guaranty;
(2) 7 years from the date the Secretary, guaranty agency,
eligible lender, or subsequent holder first reported the account
to the consumer reporting agency; or
(3) in the case of a borrower who reenters repayment after
defaulting on a loan and subsequently goes into default on such
loan, 7 years from the date the loan entered default such
subsequent time.