Bouncy Needle

[JL100]

I didn't want to "hi-jack" another thread, so forgive me if this is somewhat repetitive sounding. My speedometer needle on my '67 F100 is extremely "bouncy." The only time it stays somewhat still is at a good cruising speed. I haven't taken apart the dash just yet since purchasing the truck, but was wondering if anyone knew of the fix for this? I read on another thread about a gear of some sort, and am assuming that could be the issue...but my Dad always told me that when I assume it just makes an "A** of U & ME", so I'm gonna ask you guys. Thanks as usual!

[CrypticRacer13]

...but my Dad always told me that when I assume it just makes an "A** of U & ME", so I'm gonna ask you guys. Thanks as usual!

A guy at work says the same thing to funny

Anyways my truck does the same thing at anything under 25 it seams

[Mancar1]

Try lubing the cable 1st. If that isn't it check the speedo gear.

[JL100]

Thanks for the input guys, I'll try checking on the gear this weekend when I get some time and I'll post back my results. I know a lot of these old trucks have this issue, but the needle on mine is just a little too active to be working right.

[sublimer]

I'll be interested in the results of this thread. I have the same issue.

[cdeal28078]

Most of the time the cable and sheath just need some lubrication. It binds up and releases, binds up and releases making it jump. You can pull the cable from the tranny and speedometer, pull the cable out of the sheath and grease it up good after a good cleaning. If that doesn't fix it then it would be the speedometer head in the dash.
clint

[Joshpow]

I would lube cable and try that. Under 25 mine is jumpy and the gear is good and the cable is new. Not horrible but jumps. Old one jumped all the time. Ended up having kink in housing. New cable and better but not 100%

[Aussie_1970]

I had the same issue - where the speedo cable screws into the back of the instrument cluster was loose...like really loose..Tightened it up by hand and the problem went away...I thought that was odd but it worked

[Joshpow]

Makes sense Aussie_1970. If it got slack there itd not be real stable. Cool idea to mention.

[CrypticRacer13]

What type of grease should we put on the cable?

[Whateverman]

i just use plain ol' wheel bearing grease

[70_F100]

I use Lubriplate 105 on speedo cables.

Thick enough to stay on the core, thin enough that it won't cause the cable to bind.

[CrypticRacer13]

Cool thanks fellas

[mjhaltom]

Mine jumps too. I swapped from 3.03 3 speed to a t18 4 speed and used the same gear on the end of the cable. Didn't bounce before, does now. So I am almost certain the gear is not completely compatible.

[JL100]

Just to post up an update. I took out the gauge console and tightened the nut around the speedo cable. Very hard job due to the shortness of the speedo cable running to the back. After tightening (no lubing because I had not bought any) the speedometer hardly jumps at all, BIG improvement! Thanks for the advice everyone.