Back around December 2007, the trip odometer on my Bonneville would stick at 9/10 of a mile on the trip odometer, and it would have to be continually reset in order for mileage to accrue to the main odometer. Eventually, it just stopped working. How difficult is it to extract the old odometer, get another one, adjust it for correct mileage (in my case I'm going to add about 12,000 miles to the frozen figure on my current odometer), and re-install it?

That'* a good question. I don't know about the Bonneville, but as a general rule of thumb, in most cars, the odometers are driven by the speedometer. Take the dashboard out of the car, and have a look on the back, near the speedometer. The odometers should be on their own little board, which you can pop out and inspect for damages; in your case, it may be a disconnected cable. It would either be a cable coming from the speed sensor in the transmission up to the speedometer/odometer.

EDIT: Forgot to show you this link. Sorry, no pictures. http://www.ibmwr.org/ktech/trip-odometer.shtml

As for your missing mileage, I'm not sure what to do -- either technologically or legally. I know rolling it back is a federal offense, but adjusting it forward. I'm no lawyer, so I won't offer legal advice. Worst case, you'll have to declare the vehicle as "mileage unknown" on the title. As far as technology goes, on some cars, I've heard of there being "backups" of the mileage stored in the computer, key, ABS system, transmission computer, radio, or someplace else. If the Bonneville has the mileage mirrored somewhere, see if someone can retrieve it.

Common sense alert: Remember that tampering with the non-trip odometer is a federal offense (well, at least rolling it back is). Don't poke around with it too much. If you manage to trip the anti-tamper mechanisms, white lines will show between the numbers (at least on GM'*), and the value of your car may plummet.

if a car has a digital dash mileage is stored on thr computor. that way if the dash fails it can be reprogramed onto the new dash . not sure with analog. will ask at work tommorrow

asked our tech today he says the comp might store it he said to have it scaned to see. he wasnt real postive on the non digital dash. not much help on this one

Thanks for asking for me. I think I might know a guy who would know for sure.
From what I understand, it'* illegal to knowingly sell a vehicle with adjusted mileage/odometer issues without disclosing it. But anyways, I paid $2k for the car, and plan to drive it for a few more years (especially after a $1K transmission/TCC repair). I'm moving to NoVA in a week and would like to see if I can't straightened out before I register the vehicle. Hopefully the mileage info is stored somewhere.

Thanks for the info and link. I'll try to get behind the instrument cluster to see if anything'* amiss.

if your still having problems contact me can help you with analog speedometer not with digital....just redid mine in a 94

Do you live near Minneapolis?

I have that problem with my 94 Park Avenue so I definitely need your input.

contact me @ schultzb@srt.com