I made my decisions based on the ECM I had , the spec changes I decided to make were the only that I could make as I could not increase Temp Rating as that is the best I could find , that which matched , I could not increase the design rating as it applies to rough service which is part of the Temp rating , Again I could not change base Capacitance either as that would change the operation and design specs of the circuit .
But I was able to raise the rated Voltage as a extra measure regarding possible spikes that could have caused early failure , it is none the less the only preventative measure I could take , I also as in previous pots went to great measure to validate that the Capacitance Values would be effective in the circuit even at far lower voltages , many caps when you raise the Voltage you actually raise the applicable working voltage for that Cap to operate at it rated Capacitance value , so you have to be careful regarding that , in the case of the other Caps you listed being a lower voltage rating , that is simple , it means they have lower circuit operating voltage and can then afford to lower the rated voltage .
What I have posted in these posts is not and should not be taken as applicable to all ECM's , in every case , the ratings should be adhered to , but if you can improve the rating without compromising design function , then it is a good thing in my opinion as whatever you can improve regarding temp rating if possible and or rated voltage will just extend the life period .
So I hope all understand that you need to get the original specs on the components and then do extensive homework if you choose to raise rated voltage , design Capacitance values would never be able to be changed ot you WILL change the designed function of the circuit , but if you can raise temp rating and or voltage keeping the specified values then it is going to do nothing but add life to that you have already had fail .
And in regards to this , the proof is in the pudding , the ECM is communicating and functioning perfectly as evident by bench testing I had done to make sure there were no other issues

Guy

 

Understood. My rationale for providing the info on the caps used in other Ford PCMs was to demonstrate that the full-size truck computers of this era are somewhat unique in their circuit design, and perhaps that is why they are failing at a much more rapid pace. It would be interesting to know what the truck EEC-V PCMs look like inside.

Back to the selection of the proper replacement caps, do you happen to have the part#'s for the ones you used Guy? Even if I limit my search to Panasonic, I'm finding multiple choices of caps with the same exact specs. The ones I've tentatively selected are from the NHG series as follows...

10UF 63V 105c NHG Series PANASONIC ECA-1JHG100

47UF 25V 105c NHG Series Panasonic ECA-1EHG470

Here's a link to the spec sheet...
http://www.mouser.com/ds/2/315/ABA0000CE26-7739.pdf

An interesting note on this series of caps, which may mean something, or nothing at all.... Panasonic doesn't even offer the 47uF in 10V or 16V; the lowest voltage offered is 25. Perhaps they were problematic in the lower voltage spec parts and thus no longer offered???

 

I purchased these from Digi-Key @ DigiKey Electronics - Electronic Components Distributor
47UF 25V $.33 ea Part # P14411-ND
10UF 63V $.30 ea Part # P13467-ND

From my research as well as speaking directly to Panasonic Techs , these caps will operate at specified values well below 6.3V , so not sure about the specs you have there , but those are a different type as well , so that may be the difference .

Guy

 

Thanks Guy, I hadn't found those but indeed they look like a better choice - newer design, specifically formulated for longer life.