[storm-chasin-dodge]

As briefly as possible, here's the scenario:

Purchased a 2013 Dodge 3500 (black one in my pics) with just over 200k miles on it. Nothing for a Cummins, right? Anyway, when I purchased it, the brake light, ABS light and Traction Control light were all on, and the computer told me that service was needed on the ABS system. Cruise control didn't work, but everything was fine. No check engine light was on and the speedometer was working just fine. The sales lot that I bought it from (a diesel wholesaler) told me it was a faulty wheel speed sensor and that it was a common issue with these trucks.

1 week into owning the truck and the transmission went out. I took it to a reputable transmission shop (family friend) and we rebuilt the transmission. When he got everything put back together, the speedometer would no longer work. Upon closer inspection under the truck, we realized that both the rear wheel speed sensors were just hanging down and there wasn't even any place to hook them to (appears whoever owned it before me put a different heavier-duty rear end under the truck). Also, the vehicle speed sensor, the one that goes into the differential, is not connected and I can't seem to find the wiring harness anywhere under the truck.

Here's the dilemma: if the speed sensor was never connected to begin with, how was the speedometer working? What happened to make it quit just from having the batteries disconnected? Also, the transmission shop is worried that having these sensors disconnected might have caused the tranny to fail prematurely?

Anyone have any suggestions on how to proceed? Unfortunately, since I bought it from a wholesaler "as-is", I'm stuck with the truck... even though it's a super nice truck otherwise and I really like it.

Pics attached: Any insight would be greatly appreciated.

Thanks!

 

[Monster5601]

Any chance you can find a stock 3500 to look at for comparison. I know, not much help but in your position that is what I would do. I can take pictures of my 3500 (MY15) if that would help you.

 

[storm-chasin-dodge]

That'd be much appreciated! I was told by the dealership that the wheel speed sensors go through a hole located on the hub on the backside of the axle tubes, but where my axle tubes connect to the hub are solid and square and there are no holes. That's one of the things that are leading me to believe the rear end has been changed out. That and the fact that I can't find any wiring harness connector for the differential speed sensor.

I did find out that the truck had been wrecked last year and that it originally had an 8' traditional bed on it. It has a flatbed on it now, as shown in the pic.

:thk:

 

[Omac]

those look like your abs sensor wires. nothing to do with speed. If the speedometer was working then something is unplugged after yanking the trans out. The connector has to be there look all around including above the trans. If no luck then you have to bring it to the dealer shouldn't be an issue for them finding the problem.

 

[storm-chasin-dodge]

Thanks, Omac.

I just got back from the local dealership, per Monster's suggestion, where I went hunting for other '13 3500's. Of all the 3500's I could find, only one had the same style rear end that I had and it didn't have ABS on the rear. It DID have a speed sensor in the top of the differential.

All the other trucks I looked at had the wheel speed sensors running into the wheel hubs right behind the axle tubes and NO speed sensor on the differential. That would make sense as to why I can't find a plug on the wiring harness for the differential sensor.

I'm beginning to think that my rear end was swapped and replaced from a truck with no rear ABS. How can I find out what rear end I have???

Also, anyone have any definitive answer as to which sensor drives the speedometer? If it's not the vehicle speed sensor, then which sensor is it?

Unfortunately, neither service nor parts in my hometown Dodge dealership are much help. They just say they don't know. :i_rolleyes:

 

[Monster5601]

I have a lot of automotive engineering experience as a retiree from GM Powertrain and I know how GM and Ford do many things but Chrysler beats to a different drum.

Typically a TOS (transmission output sensor) is used to calculate the vehicle's speed. Sometimes the ABS module will calculate travel speed or a combination of the two. We used to have access to a Chrysler web site that allowed us to look at our vehicle wiring but for some reason that went away.

Relying on a dealer to help, at least for me, was fruitless. When pressed they opened up their workshop manual for me to look at. Now I know why they struggle to fix many things.

Best bet is to hit other forums that cater to the HD RAMs like diesel or a Cummins forum. This site doesn't allow links to other forums.

 

[Marine6212]

Check out batauto dot com. They have master mechanics that have wiring schematics and oem manuals

 

[ramcares]

Thanks, Omac.

I just got back from the local dealership, per Monster's suggestion, where I went hunting for other '13 3500's. Of all the 3500's I could find, only one had the same style rear end that I had and it didn't have ABS on the rear. It DID have a speed sensor in the top of the differential.

All the other trucks I looked at had the wheel speed sensors running into the wheel hubs right behind the axle tubes and NO speed sensor on the differential. That would make sense as to why I can't find a plug on the wiring harness for the differential sensor.

I'm beginning to think that my rear end was swapped and replaced from a truck with no rear ABS. How can I find out what rear end I have???

Also, anyone have any definitive answer as to which sensor drives the speedometer? If it's not the vehicle speed sensor, then which sensor is it?

Unfortunately, neither service nor parts in my hometown Dodge dealership are much help. They just say they don't know. :i_rolleyes:

I’d be happy to look further into this. Can you DM me your VIN, servicing dealer, and phone number? Thanks! – Kevin T, Social Connect Team

 

[storm-chasin-dodge]

I’d be happy to look further into this. Can you DM me your VIN, servicing dealer, and phone number? Thanks! – Kevin T, Social Connect Team

ramcares, I tried to DM you, but it says my post count isn't high enough. Can you DM me first and then maybe I can reply to yours??? - Thanks!