The answer depends on whether you received a deemed distribution of the loan amount (typically the result if the loan was in default at the time of the distribution rolled over to the new employer's plan) or you received an offset distribution where your received a distribution of the full 401(k) but a portion of that distribution was used to pay back a loan that was still current (or within the grace period).
A deemed distribution is not eligible for rollover. However, the amount used to repay the loan with an offset distribution is eligible for rollover if you can come up with that amount (perhaps a loan from the new plan) and complete the rollover within 60 days of the offset distribution. The rollover of the offset amount can be to an IRA or to your new employer's 401(k) and will continue to defer the income, thus avoiding any tax or early distribution penalty. Note, however, that if you received an offset distribution, some amount will have been required to have been withheld for taxes, so that will need to be included in the amount that you have to come up with to complete the entire rollover.
You'll need to contact your old employer's plan to find out if you received a deemed distribution or an offset distribution.
