1998 ford expedition blinking overdrive light

Over drive light flashing ? Code stored in the PCM - powertrain control module ,this will point you in a diagnostic direction .

http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c152801e51c0

if over drive light is blinking you have a problem in your overdrive inside the transmission

There's a problem with the transmission, get it to a shop right away and have it checked out. It could be a simple fix and may only cost a little, if you continue to drive it like that, the transmission will fail. The two lights are probably related.

the overdrive light blinking indicates a mechanical or electrical failure in the trans, there will be a trouble code or codes stored in the computer control module of the system, have a OBD 2 self test to determine that code(s), it is key to deciding the problem with the trans, but it is lioely the trans will need an overhaul but that all depends on the malfunction code you get.

it usually means your VSS (vehicle speed sensor is not working. Speedo working?

Go to Autozone and get free computer scan for fault code.

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You need to have it scanned for codes. The flashing overdrive light means it has trouble codes that pertain to the transmission.

When the o/d light is blinking that means there is a trany issue.My suggestion would be to have the computer scaned for codes and then get back to me and I will try to be of further assistance.

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