transmission issues...HELP!

[num1dgh]

So we're on the road & the coach is randomly loosing power. The check trans light comes on & it shifts dow to 3rd but even at that there is NO power. We were @ an Allison transmission shop in Sacramento because it did this twice before. They found nothing wrong but now it is losing power every 30 minutes or so. Advice anyone?!

[Mekanic]

Quote:

Originally Posted by num1dgh So we're on the road & the coach is randomly loosing power. The check trans light comes on & it shifts dow to 3rd but even at that there is NO power. We were @ an Allison transmission shop in Sacramento because it did this twice before. They found nothing wrong but now it is losing power every 30 minutes or so. Advice anyone?!

Have you checked your air and/or fuel filters?
Its the chepest thing to do.

[Smitty77]

If you have Silverleaf, check for error codes. Also, it sounds like you are seeing this more frequently now, so perhaps another shop could check for codes for you.

If it is a Cummins, go to a Cummins/Allison certified shop. If Cat, then a Cat shop.

Sounds like an intermittent problem between the trans and engine computers, where it is hitting both the trans (to 3rd), and now the engine, loss of power.

Not much help, and probably what you had already figured out!

Might also check in with the CC Yahoo User Group.

Best of luck,
Smitty

[Theberrys]

You can check the codes yourself. Look here for the diagnostic codes document.
https://skydrive.live.com/?cid=ae67f...2766057%212753

There is also a Operators manual that has code data, but the second one in the list is pretty complete.

There is a Allison tech over on this board that answers questions and gives help. Just add your inquiry to this thread Allison Transmission Tech Advice and he will help you.

Dick

[num1dgh]

Thank you everyone! We had some freakishly scary moments loosing jake brakes on a 6% grade...found a place to pull over, stopped, restarted & they worked the rest of the trip to OMC today for the refer upgrade. In the meantime, we did decipher the codes & it looks like a speed sensor. We're disappointed with Sacramento Truck's inability to diagnose this! We'll get it taken care of here in Oregon.

Incidentally...bought a Samsung 217 frig for the coach @ Lowe's in Eugene...no sales tax and a military discount!

[Midniteoyl]

Check the wiring and plugs/connectors...

[Theberrys]

I had a bad Speed Sensor (output on thr forward part of the transmission) and was able to replace it my self. Cost about $75 for the part. I needed the Allison serial number to buy the part and the serial number plate was covered by a mounting bracket for the muffler. A call to Freightliner customer service with the VIN and they gave me the Allison Serial Number right away. The sensors are easy to get to and have a connector into the harness. Just one bolt holds them in so the only tool required is the one wrench. There both on the drivers side of the tranny and I had plenty of room under there without jacking up the coach. If you do it yourself get some contact cleaner from an auto parts store and clean up the connector. (A tip from Allisonman)
Good luck

[jeepersrus]

I had the same problem on my 1998 Intrigue. It turned out to be a loose connection on the groung terminal of the battery. On my CC the 12v power for the Transmission started at the chassis battery. it was a 2 conductor cable that went from the battery to the module that is mounted on the ceiling in the compartment under the driver seat. It wasn't until after I cleaned every connector that I discovered a loose wingnut on the negative terminal on the chassis battery. My transmission would loose power whenever I hit a bump in the road. Fortunately I was in Connecticut when this happened. So finding bumps in the road to test my theroy was not hard.