Allison 6 Speed Gearbox Issues

[garry@rodandtube.com]

Hi Everyone.

We have a 2003 Fleetwood Bounder with the Workhorse chassis 8.1 Vortex V8 and 6 Speed Allison Transmission. When it kicks down from 6th to 5th at around 2500 RPM going to 3500RPM it is OK but then is changes again at about 3000 RPM into 4th and screams its head off at well over 4500RPM.

Is there any way that I can get this altered to change down at 2000RPM which is more like where the max torque is on this big engine.

Help would be appreciated.

Garry.

[wildebill308]

Best beat is to go talk to a Allison shop. Max torque is at 3200.

Bill

[wolfe10]

Don't have specs at my finger tips, but important numbers are what is:

Peak torque RPM

Peak HP RPM

When your foot is to the floor, the transmission should keep you toward peak HP RPM.

[wildebill308]

Horsepower: max @ 4200 RPM, Torque:max @ 3200 RPM.

I don’t remember what max rpm is but I think it is governed at between 5000 and 5500.

Bill

[garry@rodandtube.com]

Thanks guys I appreciate the help.

[campcop]

A tuner might help with rpm issues, don't know if 5 star would help. Give them a call

[obedb]

Look for a Detroit Diesel Allison Transmission franchise. Not a truck store . A real specialized operation is what you would do well to find. I have seen them throughout the US. There is one 30 miles from me.They really are the experts. Hopefully they can help you. Don't go to someone that works on them as a sideline. Most 6 speed Allison trannys are teamed with a diesel, but your unit is new enough to have an engine ECM that is talking to the transmission computer.

[wolfe10]

Actually, not sure he should go ANYWHERE until verifying that what he is experiencing is abnormal. Again if the downshift brings RPM up to around peak HP RPM, all is well!

[obedb]

Garry/ Are the symptoms you describe new behavior or are you new to the RV? Bill 308 indicates the max torque is at 3200RPM. Can you put the transmission into the manual mode and shift as needed or when the first downshift occurs, try letting up on the throttle to keep it at 3200RPM?

[five]

...Look for a Detroit Diesel Allison Transmission franchise...

FYI, DD and Allison parted ways nearly 30 years ago.

[obedb]

Go to: http://www.pennpowergroup.com/

They service Detroit Diesels and Allison Transmissions. The location in York Haven PA has been there for years. They worked on engines for me and serviced my DP's Allison in the summer of 2014. I have seen similar operations in multiple locations through out the country.

[five]

pennpowergroup.com looks like a group of independent companies under one roof...with that group, they should be able to fix just about anything. Here's Allison's recent history:

September 1970—Merge with Detroit Diesel Engine to form Detroit Diesel Allison Division,headquarters in Detroit.

December 1987--Detroit Diesel Allison becomes Allison Transmission, Division of General Motors

June 2007—GM announced that it was selling Allison Transmission to private equity firms The Carlyle Group and Onex Corporation, in a deal valued at $5.6 billion. The transaction closed on August 7, 2007.

They are on the stock market as ALSN, trading at $24.88 today.

[obedb]

They have produced excellent results for me. The location in York Haven/ When you roll in there you deal with one service desk, the Techs don't wear different shirts, and my check is always payable to the same company. Not sure about the point that you are making? The outcome is always top shelf. The info you just posted doesn't matter. They fix mechanical things and do it very well.

[manholt]

Gary.

In your owners manual, you should have a telephone number for Allison, call them. If you don't have a manual, then Google Fleetwood and download one for your coach, or call Fleetwood and speak to Tech Dept. Tell them or Allison the same you posted.

As Brett said, you may not have a problem, you just need to verify the numbers.

Carl

[wildebill308]

Hi Everyone.

We have a 2003 Fleetwood Bounder with the Workhorse chassis 8.1 Vortex V8 and 6 Speed Allison Transmission. When it kicks down from 6th to 5th at around 2500 RPM going to 3500RPM it is OK but then is changes again at about 3000 RPM into 4th and screams its head off at well over 4500RPM.

Is there any way that I can get this altered to change down at 2000RPM which is more like where the max torque is on this big engine.

Help would be appreciated.

Garry.

If you are climbing a hill or otherwise driving with you foot flat on the floor or are using cruise control when climbing it is working as it should. You are calling for max acceleration and that is what you are getting.

Bill

[five]

They have produced excellent results for me. The location in York Haven/ When you roll in there you deal with one service desk, the Techs don't wear different shirts, and my check is always payable to the same company. Not sure about the point that you are making? The outcome is always top shelf. The info you just posted doesn't matter. They fix mechanical things and do it very well.

Not making a point, just pointing out to a member who might need some service that there is no such thing as a "Detroit Diesel Allison Transmission franchise" so he need not waste time looking for one. Sounds like a great place to do business, but most of us are not in your part of the country.