Speedo Bounce

[motormayhem]

Ever since I bought my truck 1.5 years ago the speedo would bounce between 5 and 25 below 25 mph. I noticed however that with the 105+ weather that has become a bigger problem where now it goes from 5-50 below about 55. The speedo cable was chirping about 3 months ago so I pulled it out of its housing and greased it and that went away. When it is colder outside the bouncing happends less.

Any ideas on what to do to fix "The Bounce"

 

[Jones]

Usually it's a dry cable.
If you've greased it thoroughly then the cable may have a bad spot caused by chaffing when the cable was dried out.
If that's the case then replace the cable. If it breaks inside the housing it can knot itself up to the point where you can't get the cable out and have to end up replacing the housing too.

 

[rosco]

Bounce is usually always the inside cable. If they bounce, greasing them is not usually a good idea here, because of sever winter conditions that causes too much drag from cold grease. You Guys there can probably get away with the grease. But still, if they start bouncing, you might as well go ahead and change out the cable. Grease the new one putting it in.

Lee in Alaska

 

[motormayhem]

Bounce is usually always the inside cable. If they bounce, greasing them is not usually a good idea here, because of sever winter conditions that causes too much drag from cold grease. You Guys there can probably get away with the grease. But still, if they start bouncing, you might as well go ahead and change out the cable. Grease the new one putting it in.

Lee in Alaska

Severe winter here is 45* . I will pull the cable and check it...glad to hear it is probably not the head unit.

 

[wallew]

Mine did that occasionally.

It was also either 10 mph over (M1009) OR 10 mph under (M1028A2).

I had both of them rebuilt at a local shop here. It wasn't cheap. But they are not only dead bang on, but they no longer 'bounce' at all.

 

[2deuce]

The plastic post that the gear indicator cable rides around broke so I changed out the whole unit with a spare I had and found that my replacement speedo had a very annoying bounce. I ran it for 3k miles and it persisted. I had to get in there again because the fuel gage was acting like it needed the contacts cleaned along with the dash lights so I changed the speedo back to the original one that didn't bounce. No more bounce, so in my case it wasn't the cable, but something inside the spare speedo itself. The dash lights work now, but the fuel gage shows only 1/4 tank when full, I wish I replaced it too. Next time I will.

 

[1stSarge]

On Jones….. Same problem, replaced cable and all is well.

 

[rod]

Does anyone know the part number so I can buy a new speedometer cable and the plastic part that goes in the transmission?

My bounced so bad that it eventually would spin the needle like a propeller. Ended up screwing up the speedometer so I replaced it. The speedometer only bounces when I get above 65 on the interstate. Woule like to buy the parts and replace the plug and cable.

 

[wallew]

2Duece,

Is your ground wire in good shape? It's up on the side wall on the drivers side. What you are describing sounds like a bad ground. I'll give you it COULD be a bad gauge OR a bad sending unit, but you make it sound like the fuel gauge was OK prior to disassembling the dash, so I just thought you might want to check your ground.

 

[2deuce]

I didn't think about the ground because everything else works. Before I changed out the cluster the first time the other fuel gauge worked fine. The one in there now would work as its supposed to only occasionally. A full tank usually reads 1/4 tank on the gauge, lately it likes to read 1/8 tank. When it gets down to the E its near empty. I'll take a look at the ground first. Thanks