OK, this thing is starting to get to me...

When I got the truck the speedo bounced from 20-40ish & eventually sat at 0 while going down the highway. I cleaned the VSS and it stopped working completely.

Next, I replaced the VSS with a new one, and cleaned the L-shaped gear housing that mounts to the transmission and to the VSS. Still nothing.

Next, I checked the VSS wires and found no bad spots, and no resistance, so I taped them up and put conduit around them. Still nothing.

Next, I dropped the driveshaft & tightened the Yoke Nut with Loc-tite. Still nothing.

Finally, I pulled the VSS, L-Shaped gear housing, and that adjuster plate with nylon gear. The gear in the trans felt fine, the nylon gear looked fine. I cleaned everything up, filled the little key stock shaft housing with Epoxy, regreased the housing, and re-installed everything... Now the speedo bounces all over, and sometimes won't work at all.

After I first drove it, it worked somewhat bouncy, and was in the general range on the gauge of the speed I was moving. If I revved the motor, the speedo would jump up like a tach. If I was driving down the road, and let off the throttle, the speedo would be at the right speed, firm, and come down perfect like it should. But as soon as I let in any throttle, it jumps all over. What is going on?

I've done EVERYTHING you guys and the other forums have suggested, I don't know what else to do. Today I went to the local salvage yards looking for the L-Shaped gear housing thingy, but nobody even has these trucks anymore. I think that is the last part I'll replace, and if it doesn't work, I'll drive the truck off a cliff... Anyone got any suggestions???

 

Had the same problem for over a period of 7 months. Replaced the VSS to no avail. I took apart the L shaped adapter and found that one of the keystock ends had rounded off and when you would give it extra throttle, the keystock would slip and cause erratic readings. Braized the keystock back up and filed down to fit. That worked for about 6 months and then it started doing the same thing. Finally, I broke down and went to Dodge and bought the 90 dollar L shaped adapter. No problems what so ever now.

There are many different adapter ratios, in fact I went thru three different ones until I found the right one. Finally gave them my VIN and got the right one. So, be sure you give them your VIN when ordering.

 

Another thing is just to make sure that connector is tight on the speed sensor. I was on a trip and with my automatic it was dropping the tranny in and out of overdrive. I looked underneath there and i found that the clip holding the connector on was broken so i zip tied the connector to the speed sensor somehow and i haven't had a problem since. I tried to find the connector but i haven't really worried about it since it started working. Just another thought for you.

Chris

 

Same thing with me. OD would drop out no matter what speed I was at, even at 80 mph. Motor would just about jump out of the engine bay having it rev past the 3000 mark. Then I noticed that the Speed was at 0. Crawled underneath and the 'L' shaped part was just hanging there. Since putting it back in and wire wrapping the crap out of it, it has worked just fine. Still a little loose but just side to side and no longer the up and out deal.

 

I've had similar problems and would really like to know how to fix them without buying a new speedometer.
I've had my speedometer quit intermittently before but it has been working continuously now for a few years. But......the odometer quit working a few years ago and hasn't restarted.
What could make the speedometer work but the odometer not???? I'm puzzled.

 

I still haven't got around to fixing it. Like I said, the next thing I'll try is the L-shaped gear housing that mounts to the trans and the VSS. The Dodge dealer quoted $30-50 for this part and I needed to give them my VIN. I haven't had the time to get around to ordering it, but I think it should do the trick.

I've replaced the VSS, traced all wires, found no bad spots so I rewrapped & covered in plastic conduit. I've tightened the Yoke nut, the internal gear feels fine. I've checked the back of the speedometer, all seems fine. I've torn the gear housing down, and epoxied the shaft to its housing, it seems to have worked for a while although unaccurate, and finally the epoxy failed. I'm pretty sure the housing is the problem. No local area junkyards have our trucks, so I'll have to go through the dealer.