2nd Gen Non-Engine/Transmission Dana 70 with an electrical connection?

[SierraTango]

I wish I had a picture to post of it so it would make more sense being seen, but the curiosity is burning away at my mind and I can't figure it out searching the internet.

I've got a Dana 70 with an electrical connection on top of the differential and I've never seen anything like it before, I'm wondering what it could be for or is for. Does anyone else have an idea about what I'm inquiring?

Thanks.

 

[BDaugherty]

It's a speed sensor. There is a tone ring between the ring gear and carrier. The part on top of the housing that the wire plugs into is the speed sensor.

 

[SnoKing]

What he said ^^^^! SNOKING

 

[jkalchik]

Yup. Hall effect sensor for speed & ABS.

I had a really odd failure of that sensor a few years ago on my '99. Full width road hazard, crack/divot in the highway, probably 6" wide,and 2-4" deep and almost perfectly square to travel, so both wheels on an axle hit it simultaneously. The sensor became non-functional until around 50 mph, when the speedo would "wake up", and correctly indicate speed. When speed dropped below 50, the speedo settled back to zero. Fortunately, driving a stickshift, only the speedo was affected, I ran it for 4 days & another 500+ miles until I picked up a replacement sensor.

 

[SierraTango]

On my first gen manual truck the current Dana 70 does not have that sensor. Does it matter if that sensor is plugged in or not?

 

[SnoKing]

I believe you need it to make the ABS brakes work correctly! SNOKING

 

[jkalchik]

At some point, there was a switch from a mechanical speedo to electronic, and I have no idea when that took place. It wouldn't surprise me that it happened when the 2nd Gens, or the 2nd Gen 24vs were introduced.

 

[madmac74]

I Believe it changed over when they went to OBD2. My 1998 dodge has one but both my 94's don't. I prefer the older style, because the newer ones get ripped off during normal use in the bush.

MAC