Transmission failure

[Susan]

We've recently purchased a 2001 Prevost and seem to have a problem with the transmission shifting into gear. It seems to be stuck in neutral. We had two diagnostics tests run on the Allison transmission with a code 2511 showing up. They seem to think the transmission it out but we are wondering if it is simply an electronic thing.

Has anyone had a transmission go out or had this similar issue? HELP!

[dale farley]

Susan,

From what others have said concerning the 2511 code, the most likely culprit is the speed sensor. I found the info below:

The 2511 code relates to the output speed sensor on the rear cover of the transmission on the passenger side. First be sure it is plugged in correctly, then remove the connector and look to make sure the wires have not pulled loose from the sensor or backed up in the connector. It is also possible to have the engine speed sensor"The sensor at the front" and output speed sensor hooked up backwards. One person had a bad bearing in the transmission causing a problem with the speed sensor. The bad bearing produced some metal shavings, and since the sensor works on very close tolerances, the shavings interfered with its ability to read the speed of the transmission. I would check all the wiring and connectors first.

[Susan]

Guess what? Your suggestion did the trick and other than the expense of the 3 technicians, we are only out about $30.00.

[Gil_J]

It is unfortunate that when some shops see a Prevost they aim high on what they charge. I'm happy it worked out to be a quick and inexpensive fix. BTW, was it a sensor or loose connection?

[Susan]

We replaced the output speed sensor and all worked well for about an hour then we were back to not being able to go into reverse or drive. Still stranded in the KMart parking lot. Any other suggestions?

[Susan]

A sensor, we replaced the output speed sensor attached to the transmission and it worked ok for a short period of time. Now we are back to the same issue - won't go into drive or reverse. It indicates drive and reverse on the key pad but won't shift.

[dale farley]

Susan, I know you may already have, but I would make sure there is not a loose wire or dirty or corroded connection anywhere in the area of the sensor. A loose, broken or dirty wire or terminal has been the culprit in many situations involving electronic components.