Author Topic: Speedometer flutters below 10MPH  (Read 2386 times)

gcw206

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Speedometer flutters below 10MPH
« on: July 26, 2023, 21:00:32 »
1969 280SE W111 Coupe, with an automatic transmission.
My OE speedometer fluttered an acceptable amount below 10MPH.
Then I damaged the OE cable while assembling the dash.
The OE cable was replaced with a non OE cable.
Then it skipped a lot, and the new after market cable was replaced with another by the same vendor.
All worked pretty well for a while.
Now my speedometer flutters a lot below 10MPH.  (Got worse over past year or so.)
It is either the gears in the automatic transmission; the cable; or the head unit in the dash.
I have found an OE MBZ NOS cable, but am I looking in the right place?
Thanks, Galen

kampala

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Re: Speedometer flutters below 10MPH
« Reply #1 on: July 31, 2023, 01:27:11 »
There is a lot written about this issue on this site.  Try the search “bouncing speedo”

Or similar terms to bouncing.  You should find a lot of info. 

250sl - later - manual
280sl - 1971 - Auto - LSD

Aslam

ja17

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Re: Speedometer flutters below 10MPH
« Reply #2 on: August 01, 2023, 04:52:18 »
Try loosening it up a bit at one or the other end.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

gcw206

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Re: Speedometer flutters below 10MPH
« Reply #3 on: August 10, 2023, 18:37:26 »

I removed the speedometer head and cable;
Took to bench, hooked up cable to a variable speed drill;
Speedometer still jumped at low speeds;
Decided that transmission sending unit was not the issue;
I bought a NOS MBZ OE speedometer cable;
Installed, and problem solved.