Speedometer not working

sftibbs · #1 (**permalink**) 01-28-2009, 06:28 PM

My speedometer has stopped working. I started troubleshooting and I think the gears may be stripped in the transmission. I have been told the engine must come out to get the tranny out to replace the gears and/or cable. This is on a Backdraft Cobra. Any other suggestions? Thanks!

Mac VABCH · #2 (**permalink**) 01-28-2009, 06:33 PM

sftibbs,

On Backdraft car the speedometer in read from the differential and it is electric. if the BDR has a removable transmission brace the it can be removed without removing the engine....But for your speedo not working I would look at the diff or the wiring...Mac

sftibbs · #3 (**permalink**) 01-28-2009, 07:06 PM

If it makes any difference, I should've mentioned that my gauges are Autometer mechanical. Thanks.

joe g · #4 (**permalink**) 01-29-2009, 01:50 PM

Also have same car, check the wire that connects to the speedo gear on the backside of the rear end. you can see the wire by taking off the right rear wheel if you dont have a lift.
Joeg (Smokingcobra)

Cashburn · #5 (**permalink**) 01-29-2009, 05:29 PM

How does the gear attached to the cable look when you take it out? I can tell you from a lot of recent experience with the Autometer mechanical speedos they are all destined to fail at some point.

If you want to make a nice upgrade and avoid further issues with speedos and cables you should consider some gauges from www.speedhut.com ... or I can get them for you. Either way you will avoid the perpetual problems with the Autometer gauges.

Gatorac · #6 (**permalink**) 01-29-2009, 06:28 PM

The cable comes into the drivers side of the trans. 1 bolt to remove and you can pull it out and see what the gear looks like. You can do this from underneath the car. No need to pull the engine.

Ron61 · #7 (**permalink**) 01-30-2009, 02:43 AM

If the gear looks good when you take it out, get a drill and attach it to the end of the cable and have a friend watch the speedometer to see if it reads when you run the drill. If not, then you have a broken cable or the speedometer is bad. If it reads ok, then the trouble is in the transmission.

Ron

Cashburn · #8 (**permalink**) 01-30-2009, 05:38 AM

We have also battled a non-functioning right angle reverser as well. Another spot to check. It is the adapter attached to the back of the gauge.

rabbit1340 · #9 (**permalink**) 02-04-2009, 11:43 AM

If you have a T5 trans check the gear on the output shaft. Stick you finger in the speedo cable hole and see if the gear spins, if it does the little clip that holds it to the shaft broke. Dont ask how I know.