on the original Barth a cable or eletric.mine wont go above 35mph
thanks lenny

Your speedo likely has a mech takeoff at the Allison transmission and then is electronic from there to the dash. Mine gve up the ghost and wouldn't work at all. With the speedo inoperative the cruise control would not work either. Being as it was nearly 18 years old at the time, I dismantled the box at the transmission, flushed it well with spray penetrating oil and brushed it out with an old paint brush to clean it up. I then regreased it well and put eveything back together. Also cleaned all the electrical contacts I could reach too.
Don't know what of all that cured the problem but it is still going so far.
Good luck and I'd give it a try.
Don

thanks for the info I am not going to wait for the spedo to come in i will clean contacks after church tomorrow.
lenny