I have a 1997 Ford F250 diesel with 90,000 miles. The transmission made a brief grinding noise a few days ago & refused to shift into overdrive. I have decided to have the transmission replaced rather than trade for a new truck.

Has anyone else experienced transmission failure with this relative low mileage? If so, any ideas as to cause?

I haul in overdrive (mostly flat roads) but was recently told (by a co-worker) that I should always start out with the overdrive OFF and only turn the overdrive ON once I had reached highway speed.

Any thoughts, anyone? The truck has always been serviced on schedule & is only lightly used to haul a 3 horse gooseneck aluminum trailer.

Big thanks!

Bummer,
The E4OD transmission in your truck has been a pretty good transmission up until Ford replaced it with the 4R100 in 1999. You may have an issue with the front pump, definately an issue in the foreward gears. Replacing it is the way to go because the expense of an overhaul is close to the same as a replacement trans and you'll get a better warranty on the replacement. Failures like this unfortunately aren't all that uncommon. The best way to insure the health of the new unit it to do a transmission flush every 30000 miles. Do a flush, not a filter change because the flush will remove any sludge in the filter and will exchange 100% of the fluid as opposed to only getting about 50% of the fluid in a traditional pan-drop trans service.
Good luck!
Jake