Speedo Needle Bounces .. most common reason?

[CoupedUp]

'89 has low, low miles and 2.73's in the butt of her.
Needle bounces a little, but straightens up a bit as speed increases (about 70).

Wondering what the most common reason is for this?
VSS, cable, driven gear, cluster

Anyone ever experienced a cluster messed up internally where this occurs? Worries me the cluster may be junk from the factory (since the car has so few miles,12K) ... I don't see the cable being junk so quick

Swappin' in 3.55's within the next couple of weeks and already have a black 20 for speed compensation.

I realize I will probably just have to get into it, but if there is a common part that fails, that could save me some time.

Thanks,
Joe

 

[Boostin]

ive always heard that you need to lube your speedo cable when that happens. mine does it to

 

[CoupedUp]

ive always heard that you need to lube your speedo cable when that happens. mine does it too

That's the most common huh ... okay

 

[5spd GT]

I would change your speedo gear (but your going to anyways). That is very common and is the easiest to replace.

I have replaced both the speedo gear and speedo cable (a bit more involved) and mine still bounces like crazy and starts at 55mph...lol.

So I do about 120mph all the time

 

[CoupedUp]

.... I have replaced both the speedo gear and speedo cable and mine still bounces like crazy ...

Thanks for building my optimism on this one

 

[87'GTstang]

Just try to lube the inside of the cable as best as you can. It just gets dry over time and the cable gets hung up with lots of friction and resistance.

 

[ratrapp2]

i replaced my cable and vss with ford parts and mine still bounces.the heads are famous for this,not just in mustangs but older ford cars in general,escorts,taurus and more.

 

[txstang84]

i replaced the cable with the autozone special about 6 years ago, and that fixed it...it's starting to hang slightly again, but i'll be replacing it again in the not too distant future

ck your cable, see if it's touching your exhaust, that's what caused mine to go bad...besides it's a cheap fix...less than $25

 

[payupsucka]

mine does that and when i pulled my trans down the other day i noticed my speedo gear was stripped iam saying thats what does it but i could be wrong

 

[slow84lx]

I've fixed the speedo bouncing problem a couple of times by lubricating the cable...seems like I used some white grease. One time the cable was frayed and I replaced it. Fixed the bouncing each time and none was hard. The hardest part for me was disconnecting the cable from the speedo....my hands don't like that tight spot. Good luck.

 

[CoupedUp]

........... The hardest part for me was disconnecting the cable from the speedo....my hands don't like that tight spot. Good luck.

I hate that too, probably the most annoying part of a heater core job as well

Thanks for the help everybody