Noisy speedometer on 1956 Tbird

[AlaskaG]

I have a 56 Tbird with a very noisy and erratic speedometer Can it be fixed and how do you get it out to repair or replace it

 

[Buckley]

I have a 56 Tbird with a very noisy and erratic speedometer Can it be fixed and how do you get it out to repair or replace it

You need to pull the speedo cable from the back of the speedometer and spray some cable lubricant into the cable and put a small amount of light grease on the tip of the cable that goes into the speedo. If you still have some noise or erratic movement in your speedo you may need to do the same thing on the cable end that goes into the transmission. Both ends are fairly easy to get to. Worked for me. Good luck

Moderator Note- You can purchase Cable Lubricant here- https://amzn.to/3p5kwPB

 

[doug7740]

The speedometer has two main parts, the speedometer head and the speedometer drive cable. When the speedometer fails to indicate speed or mileage, the cable may be broken. Most cables break due to a lack of lubrication or a bend or kink in the housing. The cable also might break when the speedometer head mechanism binds. A jumpy pointer, along with a scraping noise, is often caused by a dry or kinked speedometer cable. The kinked cable rubs on the housing and winds up slowing down the pointer. The cable then unwinds, and the pointer jumps.

To lubricate the cable and check for kinks, the cable will have to be removed from the housing. It is not necessary to remove the housing from the vehicle. From under the dash, disconnect the housing by its fluted nut from the back side of the speedometer head. Prior to removing the cable from the housing, cover the carpet and upholstery, as the common lubricant is graphite which will really make a mess to whatever it touches. Using a long nose pliers, pull on the cable while supporting the housing. The cable should come out fairly easily, unless there is a crimp somewhere in the housing, which could be the cause of the problem by itself.

With the cable fully withdrawn and out of the car, inspect the outer surface of the core for flat and shiny areas. These indicate wear areas and you can use their position to approximate the area of the housing that may have an excessive bend or kink. To check for kinks, lay the cable on a flat surface and twist one end with your fingers. If it turns over smoothly, the cable is not kinked. But, if part of the cable flops over as it’s twisted, the cable is kinked and should be replaced.

Before reinstalling the cable back into the housing wipe it down with a clean absorbent cloth and re-lubricate it with a graphite bearing lubricant. Then feed and twist the cable back into the housing. The last 3/8” to 1/4” will require twisting and pushing to engage the square drive at the far end of the cable.

Before re-connecting the speedometer housing to the back of the speedometer head, put a few drops of lubricant on the wick in the speedometer head. I had a hard time doing this so I removed the speedometer head from the dash.

doug7740
1955 Thunderbird Blue

 

[scooter32660]

The speedometer has two main parts, the speedometer head and the speedometer drive cable. When the speedometer fails to indicate speed or mileage, the cable may be broken. Most cables break due to a lack of lubrication or a bend or kink in the housing. The cable also might break when the speedometer head mechanism binds. A jumpy pointer, along with a scraping noise, is often caused by a dry or kinked speedometer cable. The kinked cable rubs on the housing and winds up slowing down the pointer. The cable then unwinds, and the pointer jumps.

To lubricate the cable and check for kinks, the cable will have to be removed from the housing. It is not necessary to remove the housing from the vehicle. From under the dash, disconnect the housing by its fluted nut from the back side of the speedometer head. Prior to removing the cable from the housing, cover the carpet and upholstery, as the common lubricant is graphite which will really make a mess to whatever it touches. Using a long nose pliers, pull on the cable while supporting the housing. The cable should come out fairly easily, unless there is a crimp somewhere in the housing, which could be the cause of the problem by itself.

With the cable fully withdrawn and out of the car, inspect the outer surface of the core for flat and shiny areas. These indicate wear areas and you can use their position to approximate the area of the housing that may have an excessive bend or kink. To check for kinks, lay the cable on a flat surface and twist one end with your fingers. If it turns over smoothly, the cable is not kinked. But, if part of the cable flops over as it’s twisted, the cable is kinked and should be replaced.

Before reinstalling the cable back into the housing wipe it down with a clean absorbent cloth and re-lubricate it with a graphite bearing lubricant. Then feed and twist the cable back into the housing. The last 3/8” to 1/4” will require twisting and pushing to engage the square drive at the far end of the cable.

Before re-connecting the speedometer housing to the back of the speedometer head, put a few drops of lubricant on the wick in the speedometer head. I had a hard time doing this so I removed the speedometer head from the dash.

doug7740
1955 Thunderbird Blue

View attachment 4519View attachment 4520

Can you tell me how to remove the speedometer from the dash? I have the 4 screws and backing plate removed but can't seem to get the speedometer itself to come out of the cluster.

 

[doug7740]

The instrument cluster is held in place by four clips behind the dash. These clips are attached to the instrument cluster studs using nuts and lock washers. On the upper right stud, the ground wire for the instrument cluster is also attached. If you are flexible you can squirm under the dash from the driver’s door. If this becomes too painful, the seat can be easily removed to allow more comfortable access. Although it is not necessary, you can also remove the steering wheel to gain the necessary clearance when removing the instrument cluster from the dash. If the steering wheel is not removed, you can use the telescopic feature to gain 3 additional inches of clearance.

Before the instrument cluster can be removed, you must disconnect the speedometer cable by the fluted nut that attaches the cable housing to the speedometer head. You will also have to remove the wires that are connected to the fuel and temperature gauges. It would be a good idea to label these wires as you remove them. Next, remove all of the light bulbs that are in the instrument cluster. These bulbs just push in the instrument cluster and are held in place by their sockets. I would suggest that you label the bulbs as you remove them from the instrument cluster.

Once the instrument cluster is removed it must be disassembled to gain access to the speedometer itself.

doug7740
1955 Thunderbird Blue