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Topic: Transmission Temp Gauge (Read 1047 times) previous topic - next topic

Transmission Temp Gauge

Hey folks,

I have a non functioning Transmission Temp gauge on my 98 U270.  It must have recently gone out as I only noticed today that it was not reading a temp.  Question, how can you check the temp sending unit or the gauge to determine which one is out?  Also is this a common problem? Tranny is the MD3060 Allison...Thanks

Chris Reiter
98 U270

Re: Transmission Temp Gauge

Reply #1 –
Chris,
When was the last time you noticed a temp reading at the gauge?  It takes a bit of doing to get the temp gauge to move unless you're pulling heavy loads or using the retarder during a long downhill descent.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Transmission Temp Gauge

Reply #2 –
Peter,

Thanks for your reply...i really appreciate it.  The last time I noticed it working was in the early fall.  I recently took a trip to Bend in December over the MTN pass on Hwy 26, it was very cold 25 degrees and noticed that the gauge had  not moved. I did not have the retarder on due to ice...I noticed the same thing on my return trip.  Today I took it out on the freeway, it was 55 degrees here in Portland and again did not see it move...  I have gone over the Mtn passes many times over the past year, when it seemed to be working it never got over the normal temp range even with the retarder on..thoughts?

Chris

Re: Transmission Temp Gauge

Reply #3 –
Chris,
I'm not that proficient at the mechanical, but it may be that the temp sensor may be a possible source of the problem.  It may have a bad/lose connection, or the sender itself may have gone bad & needs replacement.  Otheres may give you a better idea where to begin to diagnose a possible problem.
 
 I can tell you that my trans gauge moves only a very slight bit under most driving conditions and moves only when I use the retarder during downhill descents.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Transmission Temp Gauge

Reply #4 –
Thanks PeterI  appreciate your insights

Chris

Re: Transmission Temp Gauge

Reply #5 –
I too am not an expert but since the last time you noticed it working was in warmer weather, I think it may be due to lower ambient temps. 55 degrees is still pretty cool unless you are under a heavy load for a long period of time. I wouldn't worry too much until you operate the coach in warmer weather.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Transmission Temp Gauge

Reply #6 –
Our trans temp gauge was acting up.  I found the sender near the cooling fans, cleaned the connector, and problem solved.  It moves a small amount to reflect the proper temperature, but it does move.

The EGT is a story for another time!
Matt B
1998 u-320

Re: Transmission Temp Gauge

Reply #7 –
I complained on our initial service that transmission gauge was not working. MOT diagnosed a loose connection. The gauge has only registered significant changes on a LONG downhill grade.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Transmission Temp Gauge

Reply #8 –
We don't have a retarder but our normal transmission temp is about 180 degrees, reached after several miles driving in the morning. With the trans in lockup mode (and no slipage) it stays right there, even on long grades. On really steep hills where we are in first or second (before lockup in second) or in stop and go city traffic, it may climb to 210 or even 220 degrees. As soon as we are back in lockup half way through 2nd, all of 3rd and 4th it comes right down to 180 or so. Hope this helps.

Pierce & Gaylie
93' U300/36
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)
 

Re: Transmission Temp Gauge

Reply #9 –
Quote from: Chris –
Hey folks,

I have a non functioning Transmission Temp gauge on my 98 U270.

My transmission temp is usually about the same as the engine water temperature, except when the retarder is actually doing some retarding and then it is higher.  I think the transmission temperature sender is located in an elbow on the transmission where the big hoses are that go to the heat exchanger (below the drive shaft).  There should be an electrical wire attached to the sender (push on pull off), it may have come off or have a bad connection.  Could be the connection at the back of the gage too.
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt