Transmission temperature rising

[Jim Simonet]

I purchased a 04 Patriot Thunder 505HP C12 w/ Allison 4000 transmission in January of this  year and have taken a few trips since then.  I'm starting to become concerned about the temp reading from the Aladdin system on the transmission temp.

First trip - about 300 miles each way - engine temp stays right around 188 and trans temp ~195 the entire way

Second trip - 600 miles from Dallas to ABQ - engine temp ~188 and transmission 200 to 212 at different times, would always seem to come back down to 195 if I stopped at a rest stop.  I came back home through Raton Pass in CO (no problems and no noticeable temp difference on transmission) - but through Kansas and OK back to Dallas I noticed it was now always at least at 205 to 215

Current trip - Dallas to Nashville -  engine is right there at 188 and trans is 210 - 220.  I parked for a week and then yesterday I drove it across town to get tires.  I was caught in stop/go traffic on the return back for about 1 hour.  Transmission temp really up there - 235ish.  I stopped at a Pilot to get some fuel, left the motor running at high idle for about 10-15 minutes, really didn't help much - only came down to 228.  By the time I got home and parked in driveway - it was at 245 and I shut it down.

A visual inspection of the side radiator from the outside looks fairly clean to me from the outside (compared to other pics I've seen online).

Any recommendations on my next course of action?  I'm planning on heading back to Dallas next weekend...I have struggled to even find someone in Nashville to do an alignment on the front - much less do any kind of mechanical work.

[David T. Richelderfer]

Transynd or regular transmission fluid?

ELC or regular coolant anti-freeze?

Clean radiator?
http://beaveramb.org/forum/index.php/topic,8051.msg55699.html#msg55699

[steve zannella]

Sounds fairly normal compared to my trans coolant.engine coolant temp determines fan speed and trans depends on fan so if engine coolant is normal transmission temp  may rise higher than normal.

[Jim Simonet]

Transynd or regular transmission fluid?

ELC or regular coolant anti-freeze?

Clean radiator?
http://beaveramb.org/forum/index.php/topic,8051.msg55699.html#msg55699

1.  Regular transmission fluid - sample was taken at purchase and I recently spoke with the owner at JB Lubricants about a re-sample after 3k miles.  He looked at my numbers and said don't bother - take another sample next year

2.  I don't believe it is ELC - sample was taken and nothing of alarm was noted

3.  I will give the radiator a wash/rinse with some dawn soap this weekend

thanks!

[Jim Simonet]

Sounds fairly normal compared to my trans coolant.engine coolant temp determines fan speed and trans depends on fan so if engine coolant is normal transmission temp  may rise higher than normal.

At what point is it a problem?  I'm not so much concerned with the actual temp number, its just more of a baseline that keeps going up with each trip I take...Hopefully a radiator cleaning will bring it back down to where it was the first couple of trips

[David T. Richelderfer]

http://beaveramb.org/forum/index.php/topic,570.msg3175.html#msg3175

Transynd is an expensive upfront changeover but will be good for years.

[Gerald Farris]

Jim,
What type of transmission cooler do you have? Monaco, in their infinite stupidity, designed some of the 03-04 era coaches without a transmission cooler, some with a cooler in the lower radiator hose, and others with a transmission cooler in the radiator tank. If yours is one without a cooler, and that is what your readings sound like, your temps are normal and you should not worry about any temps that are below 250 degrees.

You have several options to your transmission temp issue like installing an air to oil cooler, but you need to determine what type of transmission cooler
you have first.

Gerald

[Bill Sprague]

Within this group there have been some rare cases of transmission cooler failure where a little engine coolant got into the transmission fluid through some shared fittings and long term corrosion.   One of the signs was elevated transmission temperatures. 

As a committed worrier, I was sending transmission fluid to Blackstone Labs about twice a year toward the end of my Beaver ownership.  My thought was I might save money if I caught it early enough.

[George Harwell]

Jim
      Just some food for thought on your return trip to Dallas. If the temp continues to be of concern you may try downshifting to 5th gear and see if the temperature comes down. Hope you get it under control as sitting on pins and needles is no fun.

[Jim Simonet]

Jim,
What type of transmission cooler do you have? Monaco, in their infinite stupidity, designed some of the 03-04 era coaches without a transmission cooler, some with a cooler in the lower radiator hose, and others with a transmission cooler in the radiator tank.

I don't recall seeing a cooler now that you mention this...I will get out there and search to see if I can find out for sure.

Thanks everyone for your help

[Fred Cook]

My transmission cooler is located just behind the side radiator. One hose allows coolant in and another allows transmission fluid in to assist lowering coolant temp. Mine was leaking last year due to rust on outside so I replaced it for about $1000. The cooler itself cost around $800 from Rocore.  Luckily no coolant got into the transmission according to lab analysis by Blackstone.

[Fred Cook]

My transmission cooler is located just behind the side radiator. One hose allows coolant in and another allows transmission fluid in to assist lowering coolant temp. Mine was leaking last year due to rust on outside so I replaced it for about $1000. The cooler itself cost around $800 from Rocore.  Luckily no coolant got into the transmission according to lab analysis by Blackstone.

Ok my bad..... I meant to say assist “lowering transmission temp” instead coolant temp. Sorry

[Jerry Emert]

I have had concerns off and on for the 5 years I've had the coach.  My trans temp do the same as you report above.  Before they reach 250 I downshift to 5th and they go down rapidly.  If I stop for fuel or at a rest stop the temps go down in seconds to a few minutes.  Because of my concern I have asked Allison Reps on two occasions about the high temps.  Both told me that the 4000 was designed for dump trucks that routinely run at or above 300 degrees with Transynd.  I am not a mechanic and still have no idea what type of trans cooler I have.  The temp also seems to be very dependent on outside temps.  I have been traveling off and on this spring in lower outside temps and havent seen anything over 220 after several hours of driving.  IT doesn't sound to me like you have anything to worry about.  Good luck.

[Jim Simonet]

Thank you Jerry - your post (and others) has made me feel better.  I think the rise that I've seen is related to outside temperature more than anything else.   First trip - February, second trip April, and now end of May and it was lower 90's out when I got caught in traffic.

I think my transmission cooler is also located behind the side radiator as well.  I can't see it too well, but I do see two hoses which look
like they go to the transmission down there.

I will continue to monitor and then change over to Transynd when I get back home for a little more piece of mind.

A sincere thank you to everyone on this thread, I really appreciate it!

[David T. Richelderfer]

Just an afterthought.  Our coach had an auxiliary transmission cooler installed by a prior owner because of high heat numbers.  Since we have owned the coach (August 2012), I have noted our transmission temperature runs about 40 to 45 degrees over outside temperatures.  Yes, in 100 degree outside temperatures, we might see 145 on the Aladdin's transmission temperature, but that high a temperature is very rare in our travels.  I do not recall ever seeing a transmission temperature of over 145 degrees in almost 7 years.  I am more concerned our transmission temperatures are not high enough.