where to put a trans temperature sensor?

[steroidcontaskie]

Hi all

I have decided to install a trans temperature gauge for my auto and have been looking online about where to mount the sensor.

There are to schools of thought.

1. is to put in in the pan so you get the temperature of the fluid that is going though the clutches etc.

2. is to put it on the coolant line running out of the trans before the cooler to see the max temperature the fluid gets to.

Any thoughts on which is best?

Cheers
Edward

[Snaps]

I would say to put it on the cooling line - you want to make sure you're not overheating the trans fluid, if you are, that's what will damage the transmission, if anything. It's useless to know how hot the fluid is going through the clutches, as that's not telling you whether or not you're damaging the fluid.

[BlakeNZ]

Do you have an aftermarket trans cooler? If not, why not?(given you are concerned about trans heat).
The soarer trans pan doesnt have many places that allow clearance internally for the sensor to protrude, so pick your spot carefully if you go that way. We targeted the area of the pan furtherest from where the oil returns from the trans cooler. I tend to think the temp that the clutches see is very similar to the temp of the (portion of)fluid that is sent forward to the cooler.
However,in many ways, i like the suggestion from the above post.
120 degrees C is generally accepted as the temp level that causes damage.
I have two coolers on mine(in series). i have a higher stall convertor though.

[steroidcontaskie]

Thanks for the responses.

Yes I do have a cooler, it is a Davies Craig v8 spec one. I also have a high stall converter. I am going to install a temperature activated fan on the cooler.

I was at a gearbox place yesterday and they commented that if you have your cooler mounted to the side of the bumper (where mine is)it might not get much air flow from a dyno fan and that a lot of people cook there gearboxes on the dyno because of this. I am most worried about the temperatures during tuning.

Cheers Edward

[Evlc36]

Those Davies Craig V8 ones are pretty small - had one on the Aristo at BPU, I would recommend looking at a 20k+ BTU cooler (I run a 28k BTU B&M cooler now)

When my HKS CAMP2 arrives I have the additional sensors to monitor trans temp.

[steroidcontaskie]

You are right, they are not the biggest.

When I was looking at coolers, most of the larger coolers were just listed as oil coolers and I was concerned that there were different requirements for a trans cooler vs and oil cooler (i.e pressure drop etc).

Since I have the davies craig one installed already and have a fan it for it, I think I will go with this set up and see what the temperatures are looking like. If they get too hot I will have to put another cooler in. I have a Blitz oil cooler lying around (think it is 19 rows) and I could always put that in if I need too.

Cheers
Edward

[BlakeNZ]

the trans gets much hotter when engine is at rpm levels below the stall level.
Unlikely to cook it on the dyno. I had one cooler in front of radiator, one in a side vent, so best of both worlds really.
trans temp has never been an issue on the dyno with mine.
you could wire up the torque convertor solenoid to a switch, so you lock it "ON" while doing dyno work. This is what i do.(and enjoy the 8% higher power figures!)

[steroidcontaskie]

you mean so that the lock up clutch will be on all the time? and there will be no slippage?

Is that the normal thing to do? or will it make the trans less likely to fail on the dyno?

The trans is out at the moment, so if I am going to do it I may as well do it now.

Cheers
Edward

[Lloyd]

It's electrically switched anyway, so transmission in or out makes no difference.

The point implied above is that when the lockup is engaged you tend to get less heat created in the gearbox. The difference in speeds of the impeller and turbine is where a lot of the heat is created. If you take that out of the equation then it should all run cooler. Though it is harder on the lock up.

[BlakeNZ]

yes you are Correct. You switch the lock up "ON" whilst on the dyno(once the car is in 3rd gear).
There are plenty of spare gaps for switches to be installed on the auto shifter surround. I got a switch from a soarer at a wrecker, so it looks factory.