RV Trip Planning Discussions

Go Back   iRV2 Forums > POWER TRAIN GARAGE FORUMS > Allison Transmission Forum
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
 
Thread Tools Search this Thread Display Modes
 
Old 09-20-2015, 10:25 AM   #1
Senior Member
 
Xjaywalker's Avatar
 
National RV Owners Club
Join Date: Mar 2011
Location: Pearce, AZ 85625
Posts: 244
Hard downshift 3000MH after 6%grade

Just went through Big Horn Mtns and was doing some manual shifting to slow the beats down. Accidenatlly shifted into economy mode and then I started feeling a hard shift (or hard knock from the rear). When I noticed I had shifted into economy mode I switched back, but the noise continued. I am parke in an RV Park now and have not tried driving it this morning.

Anyone expierence this? I saw on line that you can reset the ECU by unplugging 2 cables on the ECU. Anyone know if this works? Or should I take it in to a Allison shop?

Thanks in advance.
__________________

__________________
Pearce, AZ
Xjaywalker is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 09-20-2015, 12:20 PM   #2
Senior Member
 
Skip426's Avatar


 
Join Date: Apr 2011
Location: Powell River, B.C.
Posts: 17,036
The Allison ECU could just have picked up some shifting traits from the manual down shifts and need to re-learn it's normal smooth pattern.
You could check for codes using the key pad, but until you've driven the coach for a few hundred miles, JMHO; I wouldn't be in a panic to get it to a shop.
Attached Files
File Type: pdf Allison trans codes.pdf (425.7 KB, 69 views)
__________________

__________________
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.
Skip426 is offline   Reply With Quote
Old 09-20-2015, 12:45 PM   #3
Senior Member
 
Xjaywalker's Avatar
 
National RV Owners Club
Join Date: Mar 2011
Location: Pearce, AZ 85625
Posts: 244
Quote:
Originally Posted by Skip426 View Post
The Allison ECU could just have picked up some shifting traits from the manual down shifts and need to re-learn it's normal smooth pattern.
You could check for codes using the key pad, but until you've driven the coach for a few hundred miles, JMHO; I wouldn't be in a panic to get it to a shop.
Thank you. I had not driven mountains like that it this big of a rig (40ft) with a tow vehicle. I read my manual also, it sounds like it would take a lot for me break the trany. lol.

I will run the program and look for codes. Thank you again, I was worried there for a minute.

Larry & Vicky
__________________
Pearce, AZ
Xjaywalker is offline   Reply With Quote
Old 09-20-2015, 01:18 PM   #4
Senior Member
 
Skip426's Avatar


 
Join Date: Apr 2011
Location: Powell River, B.C.
Posts: 17,036
Quote:
Originally Posted by Xjaywalker View Post
. I read my manual also, it sounds like it would take a lot for me break the trany. lol.
Larry & Vicky
The electronic controls on the engine and transmission , along with their interaction , will do everything they can to protect themselves and each other.
Note; a trans controller disconnect , would revert the controller to basic ' Learn " mode and there would be rough shifting involved until that was completed. I would only consider a disconnect to clear a code after repair , and sometimes that won't work.
__________________
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.
Skip426 is offline   Reply With Quote
Old 09-20-2015, 01:51 PM   #5
Senior Member
 
jacwjames's Avatar
 
Monaco Owners Club
Join Date: Jun 2014
Posts: 4,948
If the knocking continues it might be a problem with the driveshaft. All the energy that is transferred with a sudden hard downshift my have done something to a U-joint. If the sound continues I'd inspect the driveshaft to make sure there isn't a problem.
__________________
Jim J
2002 Monaco Windsor 38 PKD
2005 Jeep Grand Cherokee w/5.7 Hemi
jacwjames is offline   Reply With Quote
Old 09-21-2015, 08:57 AM   #6
Senior Member
 
Join Date: Apr 2009
Posts: 389
The trouble codes and adaptive parameters are written into EEPROMs so the information stays there even after a power interrupt.
The codes can be cleared using the shifter or Allison DOC. To reset to fast adapt, you must use Allison DOC.
dbarton291 is offline   Reply With Quote
Old 09-21-2015, 09:01 AM   #7
Senior Member
 
Xjaywalker's Avatar
 
National RV Owners Club
Join Date: Mar 2011
Location: Pearce, AZ 85625
Posts: 244
Quote:
Originally Posted by dbarton291 View Post
The trouble codes and adaptive parameters are written into EEPROMs so the information stays there even after a power interrupt.
The codes can be cleared using the shifter or Allison DOC. To reset to fast adapt, you must use Allison DOC.

Ran the test on the display. No codes. Resumed driving and it seems to be back to normal. Thank you
Xjaywalker is offline   Reply With Quote
Old 09-21-2015, 09:03 AM   #8
Senior Member
 
Xjaywalker's Avatar
 
National RV Owners Club
Join Date: Mar 2011
Location: Pearce, AZ 85625
Posts: 244
Skip426, thank you for the data. Ran the test on the display and no codes. Took off this morning and she is back to normal shifting.

Appreciate your help.
__________________
Pearce, AZ
Xjaywalker is offline   Reply With Quote
Old 09-21-2015, 09:05 AM   #9
Senior Member
 
Xjaywalker's Avatar
 
National RV Owners Club
Join Date: Mar 2011
Location: Pearce, AZ 85625
Posts: 244
Quote:
Originally Posted by jacwjames View Post
If the knocking continues it might be a problem with the driveshaft. All the energy that is transferred with a sudden hard downshift my have done something to a U-joint. If the sound continues I'd inspect the driveshaft to make sure there isn't a problem.
Checked the drive shaft and tranny for anything unusual. All good. Took off this morning and she is shifting normally.
Thank you
__________________

Xjaywalker is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Flat Towing Unlimited Rubicon Hard Rock BJCSF2014 Toads and Motorhome Related Towing 7 08-28-2015 04:51 PM
Starts hard? rich2008r MH-General Discussions & Problems 1 06-07-2015 05:11 PM
Norcold freezer section won't keep ice hard Pogo MH-General Discussions & Problems 8 05-28-2015 06:06 PM
Hard cold start mystery CAT Lover Caterpillar Engine Forum 31 01-11-2015 11:32 AM
Hard Water Marks donplessas iRV2.com General Discussion 15 05-08-2014 10:54 AM

» Featured Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 09:18 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.