Community Forums

Squanto · 09-21-2014, 07:24 PM

I would like to see if anyone else has experienced anything as this. While driving at 50 to 60 mph I get a vibration, the readout shows I am in 5L and it seems that the trans does not want to shift up to 6th. Can anyone compliment on this problem. It's an Alison 3000 trans.

Sent from my iPhone using iRV2 - RV Forum

jhanan · 09-21-2014, 08:00 PM

Not exactly, but when I had what I thought was transmission vibration turned out to be fuel starving in the motor - a fuel filter and oil change fixed that, and that was after I changed the trans fluid and filters on the 3000 thinking the trans fluid had gotten old. When was last time&miles for these 3 items. If your motor is a CAT the oil change is critical.

Gorlininc · 09-21-2014, 08:10 PM

Not sure what 5L means. But my Allison tranny runs smooth in 5th easily up yo 65 mph and doesn't vibrate at all.
Usually a vibration between 50 and 60 mph Id out of balance tires. Does the vibration go away at s higher speed?

96 Wideglide · 09-21-2014, 08:17 PM

Mine wont shift to 6th till somewhere in the 62-65mph range.

windsorbill · 09-21-2014, 09:37 PM

dick and Karen,

My Allison won't shift to 6th until about 62 mph. once you do shift to 6th, does the vibration go away? Is the vibration over the whole coach or through the steering wheel?

Squanto · 09-22-2014, 03:24 PM

Talked to a cummins tech and his conclusion was that it was the universal joint, 2005 HR with 400 hp are known for this problem. All the filters were changed in the first week of May during the HR maintance session. Will post after Wed. after the tech checks it out.

Sent from my iPhone using iRV2 - RV Forum

Mr_D · 09-22-2014, 03:34 PM

Driveline alignment and lubrication are critical on a DP due to the short driveline. We have a 3000 MH and Spartan now recommends lubing the slip joint and U-joints every 5,000 miles along with being sure the ride height is correct.
Never heard of nor seen a "5L" on the readout.

Squanto · 09-22-2014, 06:56 PM

The 5L is the readout I see on the Aladdin screen as it's shifting up thru the gears.

Sent from my iPhone using iRV2 - RV Forum

Stretch · 09-23-2014, 01:14 AM

5l means your tranny is in 5th with the torque converter in locked condition. There is 5 (5th unlock and ) and 5L (fifth lockup).

Gorlininc · 09-23-2014, 06:27 AM

Thanks for the info. My 2001 diplomat doesn't show that on my allusion pad, thanks.

Dutch Star Don · 09-23-2014, 04:18 PM

Two things......even though it's a pain, it's recommended that the driveshaft on a DP be lubed every 5000 miles due to the excessive stress they see.

I was at a Freightliner seminar last month and learned something new, but haven't tried it. Many coaches won't shift to 6th until 62-63 mph. They said you can shift to 6th by pushing the arrow up button, just as you would push the arrow down button to downshift.

Squanto · 09-24-2014, 08:51 PM

Thanks to all who had made suggestions on my problem, today the coach went in and had both the u-joints replaced and the vibration problem has been taken care of. I learned that these joints should be greased every 5000 miles or twice a year.

Sent from my iPhone using iRV2 - RV Forum

Mr_D · 09-24-2014, 09:00 PM

Quote:

Originally Posted by Stretch

5l means your tranny is in 5th with the torque converter in locked condition. There is 5 (5th unlock and ) and 5L (fifth lockup).

Not if you have the single digit readout like we have. All I see is the gear selected, not anything else. That was one of the reasons for getting the VMSpc which does show the gear selected and the gear attained.

1ciderdog · 09-24-2014, 09:11 PM

Seems sometimes like overkill (or over service) but on my CAT C7 I service it at about 5K, that is fuel filter, oil & filter, lube all the zerk fittings, the basic full service. We put a lot of miles on it, over 90K miles since we bought it in March 2010.