UPDATE: SOLUTION (4/16/15)
Clear Test History:
(Setup->Apex Test Execution-> click link 'View Test History'->click button 'Clear Test Data')
NOTE: The 'Clear Test Data' button completes the following 2 actions:
Deletes all entries from the ApexCodeCoverage table
Resets all the entries in the ApexCodeCoverageAggregate table to have 0 lines covered and all lines marked as uncovered This will result in seeing 0% code coverage in the Organizations estimation
Manually clear entries for the 'ApexCodeCoverageAggregate' table:
Via the Developer Console, execute the following query under the 'Query Editor' tab, using the 'Tooling API':
SELECT Id FROM ApexCodeCoverageAggregate
NOTE: Ensures there are no corrupt/invalid counts in the lines per class.
A) Highlight every row returned and click the button 'Delete Row'
B) Ensure there are no records in the 'ApexCodeCoverageAggregate' table by re-running the same query above in step 2 or hitting by the 'Refresh Grid' button as mentioned in the note above.
NOTE: This process is asynchronous. Keep checking this by pressing the 'Refresh Grid' button in the Developer console until all rows are cleared.
Recompile all Apex classes:
Do this via 'Compile All Classes' link in UI (Setup->Develop->Apex Classes->click link 'Compile all classes')
Run All Test
Now with the tables/cache clear we re-run again via the 'Run All Tests' button in UI (Setup->Develop->Apex Classes->click button 'Run All Tests')
Full step-by-step details provided here:
Code coverage steps and considerations prior to deployments
I've been dealing with this issue for the past few weeks now, I've got a running answer listed here: Develop Console Code Coverage Issues (Winter 15' Release) - Production vs. All Test
I'm willing to bet that Winter 15' made some changes to Unit Test to include things they already should have, for example
seeAllData=true test do not count towards code coverage, but in your estimated 86% you will see it counted. This only clarifies that there is a difference between perceived CC (Run All Test) and actual CC (Deployment to production)
There is an actual bug that SF has recognized but the patch is a few months out at least it sounds like. Checkout my post (link above) for more details as I have them
Also found this helpful article for clearing and getting accurate coverage amounts: https://help.salesforce.com/apex/HTViewSolution?urlname=Code-coverage-steps-and-considerations-prior-to-deployments&language=en_US