So, My Brother-in-law borrowed this truck to move some pea gravel. When he brought it back, he reported a couple of large bangs and the speedometer and the odometer were not working. (Of course).

It has a 302 and is automatic. I'm not sure the bangs had anything to do with this as this truck is a bit prone to backfiring, especially when decelerating from highway speeds. As a side note, when I bought the truck it had glass packs on it. Can you imagine on this engine? Anyway, I put it back to a regular muffler and that does seem to help the backfire issue quite a bit but not completely. At least the exhaust noise is now at a normal level.

So, I read several related threads and from those I checked all the fuses in the interior fuse box and found none blown. I also drove the truck and didn't experience any weird shifting as others had reported. I did a quick visual under the truck and nothing looks out of the rusty ordinary. I haven't removed the VSS for cleaning as the weather isn't exactly cooperating, but will do that next. Could that make both the sp/o not work altogether? Also, in perusing various threads I saw references to an overdrive light on the dash. This may be a stupid question, but I am under the impression that this truck only has D 1 2. Is there a chance this has an overdrive I've never felt it shift into? Is there something I can check to verify this?

Any help with this would be greatly appreciated. Merry Christmas to all.

 

I would think all '95 gasser automatics would have the E4OD. Is there no overdrive button on the shifter? On a '95, IIRC, the OD/OFF light is also on the shifter. Is the letter "D" on the dash callout surrounded by an oval?

And yes, VSS (or VSS wiring) failure will render speedometer and odometer both inop. They run on the same signal from the VSS.

 

+1 to madpogue. When I had the same problem with my 87 Ranger the cruise control was also not working. Pulled the codes and BINGO got a 29 "vehicle speed sensor signal voltage is too low."

 

Please define "not working". Is the odometer display blank?

I have never seen or heard of a F350 come with a 302 from the factory.


The backfires are probably caused by an exhaust leak further upstream.



The transmission in your truck is most likely a C6, there is no electronic control for that transmission therefore no "weird" shifting caused by a faulty signal.

 

rla2005,

Yes, the Odometer LCD is blank.

Sorry, it's the small gas engine 4.9L? It seems under powered to me whatever it is.

You are probably correct about another exhaust leak.

Ok, that would make sense regarding the transmission. I'm not sure how to check what tranny it is. Would this C6 have an overdrive? It doesn't have a circle around the D. Also, I've never seen any dash light referring to OD at all. However, it wouldn't surprise me if it was broken this whole time.

 

If Fuses 8 and 18 are good then you either have an open wire to the PSOM or the PSOM is bad. Common to have cold solder joints that break over the years.

A diagram for reference:



Does this truck have an inline 6 cylinder (4.9L) or a V8? If the latter it's most likely a 351 (5.8L). As previously stated I have never run across a F350 of this vintage with a 302 (5L).

The 8th digit of the VIN contains the engine code of the vehicle as it was manufactured by Ford:




If the truck did have an overdrive transmission (E4OD) there would be a button on the end of the shift lever and an O/D symbol on the **** that lights up when you turn off the overdrive. Somewhat common for these F350s to have a 3 speed C6 automatic transmission.

Check the sticker on the driver side door pillar for the transmission code. Trans code E is an E4OD. Trans code G is a C6

Another diagram to help you out:

 

rla2005,

Ok, once again you are correct. It is definitely a V8, but I assumed (I know, we don't need to go over the ramifications of that) it was a small V8 due to the seeming lack of gusto.

However, I dug out the title as the stickers on the door are faded to nothingness. The code is H so it is the 351!

Is there any code in the VIN for transmission? Since there's no button on the end of the shift lever, I assume it is the C6.

As for the wiring/cold solder joints, I will see if I can do some buzzing out of the wires. Can you tell me where the PSOM is located? I would assume (here I go again) it is under the dash somewhere?

Again, thanks for all the info...

 

Hey, while we're at it. My drivers side door is kinda wobbly and I ran into my favorite body man and asked him if it could be adjusted. I rocked it up and down and he inspected the hinges. He said the hinges were shot and needed to be replaced. I was looking for parts and saw where one could replace the pins and bushings on some hinges. I looked at the hinges again and they don't look like the pins are replaceable. Any advice with respect to this? Thanks

 

You must have a C6, since there's no OD button.

The PSOM is part of the cluster, attached right to the speedo/odo on the back side. Quickest test would be to get a junkyard cluster from a '92-'96 (or '97 F250/350) truck and swap the speedo/odo head. They're basically plug-and-play into the main cluster body. Your odometer will reflect the miles on the donor truck, but since your PSOM is hosed, you might well have lost your odometer number anyway.

 

Most of the time the mileage and tire setup are still in the EEPROM even if the rest of the PSOM is trash. This data can be read out and burnt into the replacement PSOM's EEPROM.

OR

Some have removed the old EEPROM, installed a socket in the replacement PSOM board and put the old EEPROM in that socket.

 

^^^^ Oh, good point about the tire calibration. Not as critical an issue with the C6, but still something to know about.

 

But even with all this PSOM attention, I still have to check the VSS, right? It is still a suspect as well?

 

No you do not have to check the rear end sensor with a blank Odometer.
It is not a suspect at this point.

 

^^^ Still a possibility, but unlikely, and you'll never know until you get the PSOM working. START with the PSOM; only move on to the VSS if ithe PSOM repair/replace doesn't solve it.

 

Ok, well I see a '97 250 near here in a U Pull it place. I may run out there Monday morning and see if it still has this part in it and give it a try. In the meantime, Merry Christmas everyone and we'll circle back on this next week...!