High trans temp on M944A1 - M939 chassis - after short drive

[bimota]

Ok, we took the M944A1 our Friday (been sitting about one year) and ran the generator for awhile and the big cooling fan kicked on a couple times. Then we noticed the transmission temperature gauge was pinned at 325!

Today (Sunday) we took it out for a drive and same transmission temp reading. So we shut it down and now are looking for answers.

Can anyone suggest a path to find the issue? We'll be working it Monday AM.

1. Gauge check
2. Sender check
3. ??

 

[tractors0130]

Same sender as coolant, if you can put your hand on the trans. pan, it's not too hot. Check it with a I/R gun or camera and see where you are at or swap trans. senders / gauge wires with coolant sender / gauge.

 

[bimota]

Ok, we measured voltage to the sender on the trans - it was 24 volts, voltage to water temp sender was 15.6. So either they are different senders or there is a wiring issue.

I'll get the IR gun - good idea. Hands can be put on trans when hot but just for short time. After several tries the trans temp gauge pings the needle - so suspect sensor or gauge failure and not an overheating problem. Will try the IR to verify.

 

[TEAMJENSEN]

Location of the transmission sending unit for the m939?

Sent from my SM-G950U using Tapatalk

 

[simp5782]

Location of the transmission sending unit for the m939?

Sent from my SM-G950U using Tapatalk

Top of the transmission. Where the cooler line returns to the transmission

 

[TEAMJENSEN]

Simp5782 thank you! I was able to find with your help the sending unit and now have the transmission temp reading correctly. I appreciate the help and the picture was very helpful.

Sent from my SM-G950U using Tapatalk

 

[Grond]

is there way to repair the sender what is a replacement part number? my gauge just keeps climbing up till max But the IR gun reads 170-180 on the pan about 185 on the filter so its definitely not overheating.