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Allison Transmission leaking from Vent

Yahoo Message Number: 16385

My motorhome has been sitting in an unheated garage for a good two months. This last weekend I had to go move it over slightly, the overnight temperatures in Salt Lake have been down in the 20's, 40s during the day. I started it and pulled it forward, backed up and then forward , moving a total of maybe 30 feet on hard packed gravel. Once I got out I noticed a good stream of trans fluid and found that it was coming from the top of the transmission where that vent is. No looks where it was previously sitting for two months.
I've read on forums that these will sometimes spew fluid at very extreme cold temperatures but I wouldn't think we were that cold to cause any kind of issue.
Anything to be done besides keep an eye on it, and check the levels? Maybe get it out and warmed up and drive it around short distances to see if it keeps dumping fluid. If so it would probably have to get towed to a shop.

Re: Allison Transmission leaking from Vent

Reply #1 –
Yahoo Message Number: 16411

From the Technical Service Bulletin:

Some customers may comment on a small red fluid/oil leak during cold weather. Upon further investigation, the technician may find a small fluid leak in the area at the back of the transmission by the vent.

CAUSE

This condition may be caused by fluid being discharged out the transmission vent due to a low transmission fluid fill. During extreme cold weather, (approximately -25°C (-15°F or colder), low fluid fill can cause the transmission pump to ingest air which can aerate the fluid and push some fluid out the vent.

CORRECTION

On 2001 through 2013 models, verify the transmission is full of fluid. Follow the SI fluid checking procedure to PROPERLY check the transmission fluid level using the Hot Check Procedure.

IMPORTANT: Ensure that the fluid level is at the top of the HOT band when the transmission fluid temperature is 79°C (175°F). Refer to SI Document ID# 2408059 for the proper fluid level checking procedure.

NOTE: The fluid level on the indicator may be higher on one side than the other. The lower reading should be considered the actual fluid level. The higher fluid level on the indicator should be considered splash.