Bouncing Speedometer High Speeds
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Joined: Aug 2023
Posts: 206
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From: San Antonio, TX
Bouncing Speedometer High Speeds
As the title suggests, when I am going 75+ I notice that the speedometer will bounce a lot. It seems to do it at lower speeds as well but not as drastic.
From what I have seen so far it sounds like I need to potentially swap out the speedometer cables (upper/lower) or the transducer. Before I swap out the transducer, I am wondering if there would be any benefit to attempting to clean it? I'd like to keep the cruise control if at all possible so not looking to bypass at this time.
As for the lower speedometer cable, there is a crossbeam directly below there the cable connects to the transmission. Is there an easy way to disconnect the cable or is dropping the cross beam the best way?
This is for a 1982
From what I have seen so far it sounds like I need to potentially swap out the speedometer cables (upper/lower) or the transducer. Before I swap out the transducer, I am wondering if there would be any benefit to attempting to clean it? I'd like to keep the cruise control if at all possible so not looking to bypass at this time.
As for the lower speedometer cable, there is a crossbeam directly below there the cable connects to the transmission. Is there an easy way to disconnect the cable or is dropping the cross beam the best way?
This is for a 1982
Last edited by klturi421; Aug 26, 2023 at 06:01 PM.
Le Mans Master
Joined: Mar 2004
Posts: 7,457
Likes: 1,483
From: Little Rock AR
The cables might just need to lubricated. Upper and lower. The lower one just unscrews at the transmission and transducer. The upper one is pretty short and will unscrew at the transducer and has a spring retainer at the speedometer.
The transducer can be rebuilt but I would lube the cable(s) first.
The transducer can be rebuilt but I would lube the cable(s) first.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
Its hard to say which cable is completely dry, the upper or lower. I believe all that needle bounce is just from lack of lube.
Before buying new cables, sometimes just a cleaning and lube will fix the problem.
Some cables had a plastic spring clipped on the end that goes in the tranny. Supposedly it was to snap off to prevent damage to the more expensive / more labor gauge cluster.
The cross-beam you mention, you mean the tranny cross member? Small hands and small pliers will undo the cable at the trans. It was an awful spot on automatics but it's doable.
You have to be careful which type of lube you use on the internal cable or inside the cable housing. Due to the design of the cable, the spiral can force any oil up into the back of the speedo cluster. That will ruin the workings inside. A grease is better and won't wick up the cable. I use Hoppes Gun Grease as its not affected by temps.
If you do end up buying new cables, study your parts list options:
Manual tran w/o cruise
Manual w / cruise
Upper? Lower?
Auto trans -blah blah-blah.
Before buying new cables, sometimes just a cleaning and lube will fix the problem.
Some cables had a plastic spring clipped on the end that goes in the tranny. Supposedly it was to snap off to prevent damage to the more expensive / more labor gauge cluster.
The cross-beam you mention, you mean the tranny cross member? Small hands and small pliers will undo the cable at the trans. It was an awful spot on automatics but it's doable.
You have to be careful which type of lube you use on the internal cable or inside the cable housing. Due to the design of the cable, the spiral can force any oil up into the back of the speedo cluster. That will ruin the workings inside. A grease is better and won't wick up the cable. I use Hoppes Gun Grease as its not affected by temps.
If you do end up buying new cables, study your parts list options:
Manual tran w/o cruise
Manual w / cruise
Upper? Lower?
Auto trans -blah blah-blah.
