I have a 2005 F-250 with the 5.4 in it. I bought O2 sensors Bosch #15664, but they look very different from the originals located before the cats. They look similar to the post-cat sensors. I know looks aren't everything, but I found 3 different part numbers for denso O2 sensors; 234-4045 for pre-cats, and post-cat part numbers 234-4071 and 234-4212.
Has anyone else run into this, or should I even be worried about it?

 

Finally found what I needed on Bosch's site. Same part number front and rear.

 

Ford uses 2 completely different part numbers for the front and rear. They should not be the same. Ford part numbers are 5L8Z9F472BA for the front and F85Z9G444BA for the rears.

 

The only difference in the sensors is the length of the wires.

Regards

Jean Marc Chartier

 

This is a cut and paste directly from Bosch's website.

at the following link.

http://www.boschautoparts.com/RB.NA....in=5&Make=FORD

I got them in and they seem to be functioning fine so far. I sure don't want to take them back out again, though it was not as hard as I had envisioned.

Thanks for the help.

 

Thank for that post buddy - I couldn't figure that out for quite awhile, but that's true.

I've even cut them up at one time for other reasons - I seem to remember varying in serial numbers on the casings as well - Like 867's(front) and 869's(rears) were the number differences, but the internals were Identical - same size ceramics (two white wires for heaters) / Signal and direct PCM ground -(Grey and Black wires).

I've flipped them without any issues what so ever.


The difference on the sensor itself, is exactly what Mr JMC posted. The difference in the truck is the program that determines it's duty cycle/responsibility via location - Where it's connected in the harness chain.