I don't think it is your odometer gear. I think that it would be your speedometer gear. I think that on the d series the sending unit is on the transmission. There is a little gear the the vss hooks up to and that has a tendency to strip out. I would start there.

If it is this part, here is the link - https://transmissioncenter.net/prod...y/dodge/?swoof=1&product_tag=speedometer-parts&really_curr_tax=7990-product_cat

 

Push in your trip counter on the speedometer guage. If it does not move or work, then likely the gear is broken. Pretty easy fix, I have fixed a few of them. DTR has a really good writeup that is illustrated the entire way....it shows you how to do it even down to every screw that you should or should not remove.

 

What is the DTR

 

Would that gear make the speedometer not work?

 

Anybody know?

 

I rebuilt my speedometer after the odometer quit working.
Installed the new gear and all was good for 47 miles and now the whole thing is dead where as before at least the speedo worked.

Mechanically they are separate but electrically I'm not sure.

Once my led bulb bases come in I'm taking it all apart again.

 

What consists of rebuilding the speedometer? I took the speedometer gauge out of the cluster and didn't see a whole lot to change for it. I did see the odometer gear

 

Well I just replaced the ODO gear per th wrote ups.
Didn't really mess with the speedo mechanicals but it does all kinda come apart in your hands so I might of mess something up.

Looking into wire harness though, thanks!

 

Just a thought. when I bought my 93....My speedometer didn't work on the way home,then one day it started bouncing around. I started with the VSS, and the adapter behind it. No dice. Long story short, where the wires go through the fire wall rubbed through, and caused a direct short. Move your wiring around and see if it starts to work....Easiest check before you start taking stuff apart...

 

did the '89s have mechanical speedos? might be easier just to go back to cable driven speedo and be done with it.

 

I have a gas '91 D250 with the problems you describe. I removed the dash and disassembled the speedometer/odometer. It contained two tiny blue plastic gears. One of the gears had quite a few of the very small teeth missing. Since the gears were covered in light grease most of the teeth were still floating around.
This speed/odom unit was apparently also used in several car dashes. The broken teeth were not uncommon. I found a company that sells replacement gears and ordered them. I believe the company also serviced the units if you wanted to send yours in.
If you decide fix this, I recommend that you send in your unit for the following reasons:
-Working on small things was not foreign to me. Even so, this was challenging. Removing the dash is not too bad, but be very careful not to break the string connecting the shifter on the column to the drive indicator on the dash. It will have to be disconnected by loosening a screw, and must be reconnected in the correct position or Park, Reverse, Neutral etc. will not show correctly.
-Since the loose teeth were in the grease, I knew I must remove all grease and start over clean. I was almost 100% successful in this endeavor as the odometer worked flawlessly for 6 miles when it was reassembled.
-One other thing. The needle on the speedometer can be removed by pulling it off. If possible, you should mark the position of the needle with relation to the shaft BEFORE removing it. 0 MPH is NOT the correct position for re-assembly. It is probably something like -10 MPH. My suggestion here would be: The needle is stopped by a pin at 0 MPH. Carefully lift the end of the needle so that it may go below zero. Mark the position of the needle at rest and use this for alignment at re-assembly. (I did not do this.)

Good Luck!

 

On the last one: Misaligned gear indicater; You will have to take the whloe module out, or you can do the following; Take the covers off the sterringwheel cloumn in the cab, remove the fusebox cover. you will see to bracket mounting bolts one on each side of the column , do not take the nuts off, un-do them just enough to beable to get the instrument cluster cover off and out. Note: at the bottom-side of the cluster, you will see a thin green string, at the end of the line is a clip, note which position the clip is in. there are 3, gently un-do the clip, " medical hemostats work ideally for this procedure" gently pull on the string and note the position of the indicater. It is highly probable that the spring has weekend over time, if that is the case, you will have to replace the spring, remove the entire cluster, once cluster is out, look at the bottom of cluster, you will see that piece will seperate from the cluster, once removed carefully dissasemble the unit, remove the,spring, replace, and put back togather. You might want to get orange instrument needle paint in case yours is faded. Good luck.
By the way, have same problem with my odometer/speedo, found a place in PA. that will repair them if you are intrested? Sent mine out, got back in 2-weeks works great