Transmission Temp gauge

[j_boucher]

Anyone add a transmission temperature gauge ? I have an auto meter one in the garage left over from another project trying to repurpose it

 

[Ronmar]

Anyone add a transmission temperature gauge ? I have an auto meter one in the garage left over from another project trying to repurpose it

Planning on it, working on a location for the sensor. There is a oil sample port on the trans fluid line to the heat exchanger/cooler but it is small(1/8NPT) but that seems like an ideal place to sample. might have to put a T fitting and a small bleed line back to the transmission to create a tiny flow for a reliable temp sample port there...

 

[j_boucher]

Planning on it, working on a location for the sensor. There is a oil sample port on the trans fluid line to the heat exchanger/cooler but it is small(1/8NPT) but that seems like an ideal place to sample. might have to put a T fitting and a small bleed line back to the transmission to create a tiny flow for a reliable temp sample port there...

I was thinking same area but wasn't sure if there was a port on the transmission itself

 

[Ronmar]

I was thinking same area but wasn't sure if there was a port on the transmission itself

I havn't come across one that I like yet. There are of course drain plugs but kind of exposed on the bottom of the control module. All the other ports I believe are pressure test ports so might not have any real fluid flow there. I have not seen one indicated specifically for temp sense, Allison does it on the control module internally...

It might be fairly easy to drill and tap a sensor port into one of the access covers on the transfer case. The transfer case has a steady flow of fluid from the center section created by the scavenger pump, so might give a useable temp reading...

 

[GeneralDisorder]

Trans temp is monitored by the TCM and there's a light for over-temp in the annunciator panel.

The data is also on the CANBUS so if you install something like the Bluefire dongle, etc you can display trans temp on a tablet or phone.

These trucks have pretty good transmission cooling and huge radiators with a ton of coolant (~12 gallons - which is the usual system capacity for twice as much engine [C15]). It's difficult to overheat them under normal conditions. I would monitor it a bit on the bus and then decide if there's even a reason to install a gauge - depending on your use case of course. If you are HEAVY towing through the desert it might be a good data point. For the majority of us that run ~25k lbs or less GVW you are unlikely to ever tax the cooling system. If your planning to tow with a 1088/89 then sure - what the hell.

I used to want all kinds of gauges but the reality is that in the vast majority of cases they are just sensory overload and not particularly useful. If the trans is overheating then chances are the engine coolant played a role, the engine is also overheating, or the transmission is spanked internally and slipping so it's overheating the fluid.... in which case it's not long before it needs a rebuild anyway so overheating is likely a short term problem to be followed by a period of not overheating because it no longer drives.

If you're determined to do it, I would weld a bung into the one end of the cooler near the hose ports, etc. Or find/make a fitting to install the sending unit inline with the trans fluid to cooler hoses.

 

[Ronmar]

AO trucks: "Busses? We don't got no stinking busses"...

 

[MatthewWBailey]

If you're determined to do it, I would weld a bung into the one end of the cooler near the hose ports, etc. Or find/make a fitting to install the sending unit inline with the trans fluid to cooler hoses.

There's an ORB male to ORB female fitting with an NPT "t" that I saw at the shop when they were remaking my cooler lines. Was going to use it to replace the integrated trans fluid sample T that's made on the factory lines (that one thats built into the hose end) But I decided to go with simplicity. "No stinking sample port!"

Or you could use a run tee like this one and just adapt the sender to a JIC fitting-ended hose..

 

[GeneralDisorder]

AO trucks: "Busses? We don't got no stinking busses"...

True. Soon to be in the minority though since all trucks from late '99 on are fully setup for J1939/J1708 coms.

After 1999 all trucks have busses. And your WTEC II has some kind of live data though I'm not sure if it's J1708 compatible..... the diagrams just say serial communication and I haven't played with one or looked into what it takes for DOC to talk to it. And your CTIS (well not your manual system but A0 factory CTIS anyway) is J1708 as well. You only lack the wiring and even that is easy since J1708 doesn't require any termination. So it's just a couple wires and a diagnostic plug.

It is also possible to use a J1939 gateway to bring the engine sensor data into the bus so it can be integrated into a glass display, etc. Veratron (VDO marine) has CANBUS gateways for diesel marine applications to do exactly that. And their gauges are pretty neat too.

 

[Ronmar]

Yep, the bussed data has some cool options For an engine wi0th an ECU. The WTEC 2 comms are I believe to their own standard, its probably similar though. For comms with it, they spec a particular Allison pro-link cartridge, or the use of the Allison doc software. I havn’t looked into the particulars either, but probably should so I can set up the gear/downshift pre-select for my ex brake… might also be cool to play with a few other optional features/configurations…

as for CTIS, nothing left to talk to on my truck

 

[j_boucher]

I havn't come across one that I like yet. There are of course drain plugs but kind of exposed on the bottom of the control module. All the other ports I believe are pressure test ports so might not have any real fluid flow there. I have not seen one indicated specifically for temp sense, Allison does it on the control module internally...

It might be fairly easy to drill and tap a sensor port into one of the access covers on the transfer case. The transfer case has a steady flow of fluid from the center section created by the scavenger pump, so might give a useable temp reading...

I believe I used a pressure port on my Broncos transmission back in the day , but like you unsure if the allisons would work