Just bought a 2001 F250 basic stock truck. Is there any way to find out the build date of the truck to see if I have the mechanical diode? I know they stopped using it on November 25, 2001, but that would be a 2002 model, wouldn't it? When did they start using it?

Am I doomed?

 

Truck build date is on sticker attached to drive door jam.

Info I have saved.

Mechanical Diode Tranny Build Dates2001 vehicles equipped with 4R100 transmission, having a transmission build date between
7/27/2000 and 3/23/2001.
Roland (mueckster) 04-15-2008
The trans does have its own build date located on the tag on the trans case (left side ,rear).
4th line down should show BD- #Letter##. This is the build date year/ month/ day.
Example : BD-1D28 1=2001 D=April (A=Jan, B=Feb...12=Dec) 28=Day of Month.
Using his example tranny Build Date is Jan 28, 2001
　
Mark Kovalsky 01-03-2009
The mechanical diode was in the diesels from the start of 2001 model year (July, 2000) and left production in March, 2001.

Cody (cleatus12r) 01-03-2009
If anyone is still interested, the "mechanical diode" was the replacement for the one way roller clutch previously (Intermediate one way clutch) used in the E4OD and 4R100s. After Ford found out that the diode wouldn't work in the gasser trucks (they exploded when shifted at 5300 RPM), they decided that they should stick with the proven and slightly more robust design. It is a mechanical device that allows rotation in one direction but not the other. It is used for the 1-2 shift when in drive range. When the "diode" was used, it replaced the roller clutch with a sprag that is inherently weaker. High power/high RPM 1-2 shifts are what kills the intermediate one way in the diesels.

Mark Kovalsky 01-03-2009
The gas engine trucks blew up the diode at 4600 RPM if the driver lifted his right foot just as the WOT 1-2 shift started, then put it right back on the floor. The person that discovered this was able to do it on 100% of the trucks he tried it on. That's why they left it in the diesels, they couldn't run 4600 RPM.

 

This is good info, I'll have to ck my 2 but they shouldnt have it but you never know. Thanks Robin

 

Thanks for the help. Mine is a May 01 build. So I seem to have avoided the mechanical diode.