Trans Oil Overheating in Campground

[Joe Lee]

Hi!  I ran into a new problem in my ‘96 Crown Royale. When I was maneuvering in a campground in very close quarters, my transmission oil temp when up to over 300 degrees. I had to change campsites later in the week and I could see the temp raising again. Temps are good under normal driving conditions. 
 

Please share any ideas!

 

Thanks!

[klcdenver]

It could be one or more of several items causing this.

1. Turn jake brake off when idling and maneuvering for parking. 

2. Low fluid level

3. Tranny radiator not circulating coolant fluid properly. 

Try the first 2 items first because they are the cheapest fix before pulling tranny cooler.
 

 

 

 

[Dr4Film]

Wow! Over 300F is way too high.

What specific transmission do you have and what type of fluid is in the tranny? Being an older coach and transmission type it makes it more difficult to assess.

Most newer Allison transmissions now come with TranSynd Fluid.

TranSynd is rated for not far over the 300F level and only at short term intervals.

My average transmission temp range it 185F to 200F. The latter is when I am climbing grades.

I would take your coach to a Allison Service Center and have it professionally diagnosed and repaired.

Those transmission are not cheap if you blow one up.

[96 EVO]

I've seen about 220deg in a traffic jam, creeping along at walking speed for over an hour.

Low speed manuvering is the worst thing for trans temp. Torque converter constantly slipping, generating heat.

 

Over 300 is excessive! Sounds like you have a problem. Could just be dirty filters.

[Fonman]

Three quick questions:

1-Did you just come off the road before the jockeying?

2-How hot does it run on the hwy / or in other words how hot to start with?

3-How long did it take to reach 300? Not unusual to take some time getting into the only spot left these days.

Could be as simple as a dirty trans cooler, fan not working properly, temp sender bad.

 

[JetAburner]

Just a coincidence. I was just reading through my Allison operator's manual for service scheduling purposes, and the read your post. On page 12 it says to not "idle in reverse for more than 5 minutes.  Extended idling in reverse may cause  transmission overheating  and damage". Sometimes we do find a situation during maneuvering that takes longer than usual. Maybe this applies to your situation.

This also apply to idling in Drive as well.

[jacwjames]

I got concerned last month as I took my coach for a run after changing filters and while backing into my garage it got up to 230F.  I have to back up a slight grade coming in at an angle.  Took me a couple tries to get it lined p and backed in.  This is a new garage so don't have much history on if this was normal or not. 

Since then I've pulled an oil sample and sent it in to JG Lubrication for analysis, it came back OK.  I also flushed my oil cooler, which in internal to the radiator, it seemed to flush fine. 

I checked my manual, says the same thing about idling in reverse, but it is on page 22.  Makes me feel a little better knowing the reason for the increase in temp.

[Joe Lee]

Thanks for all the ideas!  Since I owe an old coach, she continues to challenge me.  I appreciate all the comments!