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Transmission Temp of almost 300

Yahoo Message Number: 72131
Before we left San Diego I had the transmission completely serviced with new oil and a complete check up by the Allison Dealer. It could be my imagination but since that time the temp. has seemed to go almost to the end of the gauge, especially when in city stop and go traffic. The engine temp has remain cool.
We are currently just outside of Annapolis Maryland and will be looking for an Allison Dealer. Does anyone have any idea what I can do or check ?

Re: Transmission Temp of almost 300

Reply #1
Yahoo Message Number: 72145
Stan,

Stop and go traffic in hot weather is the worst condition for transmission temperatures. I suggest two things.

1. Be sure that your engine idle is not set higher than about 600 RPM. My coach has a rocker switch that allows me to set it up as high as 800 RPM so yours may also.

2. When sitting in traffic put the transmission into neutral. This is a pain in the rear but will help drop temps from levels with which you are uncomfortable.

Good luck.

George in Birmingham
'04 Allure 31038
George in Birmingham
2003 Magna 6298

Re: Transmission Temp of almost 300

Reply #2
Yahoo Message Number: 72151
Stan

I totally agree with George. A couple other thought's. Your sending unit is on the trans outflow line to the cooler and displays the highest temp of the fluid and not necessarily the internal trans temp. The people who have the electronic display of engine and trans temps have confirmed that in other posts. By following the placing of the trans in neutral whenever possible and driving on hot ambient days, we are able to maintain trans temps below 230 indicated.
Ned Herrmann

06 Inspire 51677

Re: Transmission Temp of almost 300

Reply #3
Yahoo Message Number: 72152
The reason for such temps in stop and go is the torque converter does not lock up in 1st causing the oil to be worked hard. My trans seems to lock up in second at a certain speed, it feels like it shifts but it is still in second. Until the converter locks, it is heating oil. This is normal. First gear running heats the oil very quickly. To counter, as others suggested, shift to neutral when stopped. Adding to that, is to rev the engine a bit to speed up the fan and oil circulation. Be careful the engine is back to full idle before shifting back in gear. Another thing is to lock it in 3rd or 4th to keep the engine revs up to speed fan and oil circulation when in town. The biggest fix is to get out of traffic and run at road speed if possible. Temps should drop fairly quickly. And remember if towing, every stop and start is getting lots of weight moving. Another trick would be try to not stop at the lights by timing your arrival, not always easy. If you are see the 300 out on the road there could be other problems, if just in stop and go, then most likely normal. If it gets to the end of scale with above driving tips, then may need to pull over, put in neutral and put engine on high idle till temps drop to normal.

Leonard

97' Magna 5418

Re: Transmission Temp of almost 300

Reply #4
Yahoo Message Number: 72153
Another thought: if you have seen lots of the 300 temps., then you may need to have the oil changed lots sooner then later. Might want to have that discussion with the Allison shop. Service lots cheaper then a rebuild.

Leonard

Re: Transmission Temp of almost 300

Reply #5
Yahoo Message Number: 72163
For an ideal Mike.

http://waynestransmissions.com/2010/07/20/the-secret-to-extended-automatic-transmission-life/
Not sure how it effects synthetic but think synthetic will go twice as long as petroleum, but service life still cut short. And yes, if a transmission has been badly overheated, $6000 to $8000 buys a lot of oil changes. Correct the overheating cause and a change may be what is needed. 300 degrees is way hot for any oil and will have very adverse effects in short time. Even if the oil can stand it for short time, that amount of heat will bake the seals and internal "O" rings making them brittle and hard leading to oil leaks and other failures.

Think this answer your "question".

Leonard

97' Magna 5418

Re: Transmission Temp of almost 300

Reply #6
Yahoo Message Number: 72178
Stan,

I had the same problem with my Allison transmission, temperature would reach 250-300 degrees in heavy traffic or under load conditions. To control transmission temperature I installed a transmission cooler and went to synthetic oil. I have not had a temperature problem after making that change. Transmission temperature holds constant between 185-195 degrees.

Thanks,
Jon

2004 Inspire #51008

 

Re: Transmission Temp of almost 300

Reply #7
Yahoo Message Number: 72183
Thank You for all the information regarding Temp approaching 300.
I checked the level of fluid and everything was OK. I called Allison, and they indicated that temperatures of 270 plus are common. the Allison Mech. recommended as many of you did to place the transmission in neutral while at a stop and increase the RPM. For peace of mind I think I will look into a transmission cooler as recommended by CC owner.

Stan 2005 Inspire