M1009 Speedometer System Question

[CARNAC]

I've had ongoing issues with my speedometer that originally was OK but then after a lub job while on the road it started going goofy and now outright doesn't work other than the occasioal bounce and on rare occasions reading the wrong speed (like 15 mph while actually driving around 50).

I took apart the sensor and cable and speedometer and lubed everything. No go. Then replaced the cable. No go. Swapped out the speed sensor for another used one that was working. Nothing. So I attached a drill to the speed sensor while it was attached to the cable and speedometer----it turned at the anticipated 35 mph (or about that since soldier B was a 9 year old girl that hasn't done anything like this before).

So there's a piece in the bell housingthat would be the next issue--correct??????

Want to confirm that the part in the bell housing is the same in all the other CUCV series as the M1009? If anyone has one that is functional, let me know.

 

[Ken_86gt]

The parts are not the same between the 08 and 09, different tooth count on the speedometer gear. The speedometer gear that goes into the bellhousing is plastic- the teeth can shear off over time due to age or mechanical binding of the cable or adapter. If you take it out take note of the alignment arrow that will match with the tooth count of the gear used.

You also have a converter that mounts between the speedometer cable and the gear- this converter also has gears inside it that can shear. There is a thread that shows how some have taken apart and re-lubed them.

 

[CARNAC]

Thanks. Guess I'll be searching for one or both parts.

 

[41cl8m5]

The plastic gear that is inside the trasfer case can malfunction. If the gear reducer that attaches to the transfer has a "load" on it (dry reducer and/or speedo cable) the square input on the inside of the plastic gear can get stripped out. It will look like its ok but the metal shaft (from the gear reducer) thats goes into the plasic gear can move in and out and can give faulty or no readings at all.

After replacing the speedo cable, I still had the same issue. So I removed the little gear reducer on the transfer case and drilled out the rivits and cleaned it up and relubricated it and used screws to put it back together, still same issue. I removed the gauge cluster again and the drove the truck with no movement of the speedo cable, I then removed the little gear reducer attached to the transfer case and attached the cable directly to the transfer case, drove the truck again and found some movement if the cable was pushed all the way in. If the cable was just a little out it was became erractic a little more out and stoped moving all together. Bingo the plastic gear must be it, I replaced the gear and it now the speedo works like it should.

The plastic gear is the same for all the chevy cucv's, the addition of the add on gear reducer is to adjust for the 3.08 gear ratio. All the other cucv's will not have the reducer. The plastic gear is color coded by GM and the one you need is the yellow one, its also the hardest one to come by. Before you remove the round cover/housing from the transfercase make sure the area is clean and look at the position of the round housing in relation to the number marks, so putting it back in with the new gear will be much easier and faster. I learned that one the hard way.

Sounds easy but with getting parts start to finish took me 4 weeks.

good luck!

 

[RedneckMilenko]

Where do you think you can find the reducer? I have been driving mine for the past year trying to calculate my speed but at 60 mph my gauge shows 45 mph. I've had no luck finding this reducer, mine didn't have one on it to service when I got the truck.

 

[212tonsoffun]

Hi Carnac! I was reading your blog regarding the VIN numbers and your criteria on what info you needed and the blog was closed, is there any way I can still give you info on our vehicles information and to get some help from you on this. (I seen that you don't like private messages, so I thought this would be sufficent. Please let me know. This is our first time on here so not sure if this is acceptable?
Thanks for your time and help
Lindsey and Woody

 

[Barrman]

If you can't find the yellow gear, pull your reduction box and very carefully cut a strip of aluminum foil that can make 1 or 2 wraps around the male part that goes into the yellow gear. I used a dab of super glue on mine.

Mine was doing the same thing as yours and I greased or replaced everything else in the system. I did the foil trick and it worked great until I smashed the cable off roading with the transfer case linkage because I didn't secure the cable bracket under the drivers seat when I swapped cables.