Vehicle speed sensors. 94 k3500

[StevesHDgarage]

You can still get a scanner for OBDI and see your speed as well as other stuff.

Got it fixed today and the trans is shifting and speedo is now working. I replaced the furthest forward sensor first and that did nothing, then replaced the one at the back of the transfer case and BOOM that worked. The other one that is not connected I believe is the output sensor if you have a 2wd vehicle.

 

[Supercharged111]

The rear tranny sensor is only 2wd like previously mentioned. The 4wd trucks didn't get the reluctor installed internally so a sensor there wouldn't work anyway. As you found, the rear sensor is for the speedo but the front sensor is for the PCM to calculate slippage.

 

[stutaeng]

Got it fixed today and the trans is shifting and speedo is now working. I replaced the furthest forward sensor first and that did nothing, then replaced the one at the back of the transfer case and BOOM that worked. The other one that is not connected I believe is the output sensor if you have a 2wd vehicle.

Awesome! So like $25, or however much the sensor costs?

 

[stutaeng]

You aren't kidding; it is really hard to see those sensors down there. I went to look, and I think I saw the rear one on the tranny did have a connector, but not really sure.

I really needed like an inspection mirror or something to take a good view. It's cold and wet outside !

 

[StevesHDgarage]

The rear tranny sensor is only 2wd like previously mentioned. The 4wd trucks didn't get the reluctor installed internally so a sensor there wouldn't work anyway. As you found, the rear sensor is for the speedo but the front sensor is for the PCM to calculate slippage.

Great info, thanks man.

 

[StevesHDgarage]

You aren't kidding; it is really hard to see those sensors down there. I went to look, and I think I saw the rear one on the tranny did have a connector, but not really sure.

I really needed like an inspection mirror or something to take a good view. It's cold and wet outside !

Yea that rear sensor was a pain to see with all the wiring in the way, but hey we are a little more educated now.