Thread: Fitting TM4 to Discovery 300TDI auto

bumpy......

I had aTM2 on my D1, and ended up putting the sensor on the RH side of the head slightly back from the front as there was a suitable bolt to attach it with (possibly a bracket or clamp of some sort IIRC).

Initially I tried it on the front of the head near between the thermostat housing and the exhaust manifold, but found it was influenced too much by the manifold.

Sorry - can't help you with a good location on the transmission.

Steve

update:
I am going to attach the engine sensor to the bolt on the DS front of head as described by Steve.
For the transmission my plan is to epoxy the sensor to the large nut on the trans oil cooler line where the sender unit is. I assume that this is on the return line so it will catch the post cooler temp (?).
As for the display unit, not sure but it will either be up on the steering binnacle attached by velcro (display unit is only 28 or so mm thick so wont obstruct instrument cluster significantly) or where the ash tray currently is...leaning to the former as the display will be easier to see there.

Originally Posted by Linds

update:
I am going to attach the engine sensor to the bolt on the DS front of head as described by Steve.
For the transmission my plan is to epoxy the sensor to the large nut on the trans oil cooler line where the sender unit is. I assume that this is on the return line so it will catch the post cooler temp (?).
As for the display unit, not sure but it will either be up on the steering binnacle attached by velcro (display unit is only 28 or so mm thick so wont obstruct instrument cluster significantly) or where the ash tray currently is...leaning to the former as the display will be easier to see there.

I wouldn't use epoxy to attach the transmission sensor as its a poor heat conductor. Also if you decide for some reason that you need/want to move it you'll have a hell of a job getting it off.

For a start, how about just clamping it on with a hoseclamp or similar. Even better if you have some heat conducting paste to put on it. Its used for electronic heatsinks and looks like a white grease. Likely places to buy it are computer or electronics places (eg Jaycar).

I've got the TM4 on my County, with the display down near where the ashtray would be on a D1. I find with the LCD display its hard to read (compared to the large bright LED one on the TM2), so if you can put it up around the binnacle as you're thinking might be better.

Steve

Originally Posted by Linds

update:

...For the transmission my plan is to epoxy the sensor to the large nut on the trans oil cooler line where the sender unit is. I assume that this is on the return line so it will catch the post cooler temp (?).....

Linds. I have an inline probe type temp sensor and fitted to the hose just 'upstream' of the factory hi temp warning sensor where you are proposing...works well.

The quirky thing to note for the ZF4HP22 (mechanical box) is this line is 'upstream' of the cooler fluid circuit for all gears 1-4. However, when the converter locks up the actual cooler flow circuit reverses....thus the temp sensor is then downstream of the cooler. This explains the rather sudden and dramatic temperature drop you will see when the TC lockup occurs, aside from there being no TC slippage action.

Originally Posted by stumps

Linds. I have an inline probe type temp sensor and fitted to the hose just 'upstream' of the factory hi temp warning sensor where you are proposing...works well.

The quirky thing to note for the ZF4HP22 (mechanical box) is this line is 'upstream' of the cooler fluid circuit for all gears 1-4. However, when the converter locks up the actual cooler flow circuit reverses....thus the temp sensor is then downstream of the cooler. This explains the rather sudden and dramatic temperature drop you will see when the TC lockup occurs, aside from there being no TC slippage action.

Hi Stumps

What kind of temps are you seeing on the trans - around town, on highway, off road?

That is weird that the flow direction changes..how is that?

thanks

Hi Linds,
Varies with load, road, ambient etc, but in summary something like the following:

Scenario 1:
In 3rd/4th gear up extended big hill climbs, big load onboard during the hot recent weeks, could see up to 115o C (not locked ofcourse). I can see why some would get the factory warning light come up as this I think is set around 125oC. Same situation but a bit faster for TC lock up...75-80oC.

Scenario 2:
Around town/local driving more normal ambient temps....70-85oC unlocked .....60 oC locked.

Yes I agree on the fluid cooler flow path reversal..it is weird. I did not believe it initially, but upon scouring the net on other ZF forums you start to see it mentioned....somewhere on here it is mentioned also. Ashcroft state it too somewhere when people asked about installing an inline filter to the cooler...as in don't do it for this reason!

I can see good value as others have done of installing the P38 cooler esp if doing continual heavy load work.

Originally Posted by Linds

Hi Stumps

What kind of temps are you seeing on the trans - around town, on highway, off road?

That is weird that the flow direction changes..how is that?

thanks

Interesting. I have fitted the sensors and have the display in a temporary position attached to the transmission tunnel trim. I havent driven it in any extreme or even heavy conditions yet but this is what I see so far:

Engine: after 10-15 minutes it will get to 82 to 85 and stay there. Interestingly the std gauge is in its normal position when the head temp is at 70. But I suppose there is a time lag on the head temp so probably correct.

Trans: seems to run very cool. takes ages to get up to 60 - 70 around town. Then when on hwy ( ie trans in lock up) it drops down to about 50 ( this was on a 30km run in 35degree ambient temp). When I pull up at home and put it into park...the temp trickles upwards-didnt expect that??
Trans has full synthetic fluid.

Anyway need to do a lot more observing across more extreme conditions before I decide on the alarm settings.

Originally Posted by stumps

Hi Linds,
Varies with load, road, ambient etc, but in summary something like the following:

Scenario 1:
In 3rd/4th gear up extended big hill climbs, big load onboard during the hot recent weeks, could see up to 115o C (not locked ofcourse). I can see why some would get the factory warning light come up as this I think is set around 125oC. Same situation but a bit faster for TC lock up...75-80oC.

Scenario 2:
Around town/local driving more normal ambient temps....70-85oC unlocked .....60 oC locked.

Yes I agree on the fluid cooler flow path reversal..it is weird. I did not believe it initially, but upon scouring the net on other ZF forums you start to see it mentioned....somewhere on here it is mentioned also. Ashcroft state it too somewhere when people asked about installing an inline filter to the cooler...as in don't do it for this reason!

I can see good value as others have done of installing the P38 cooler esp if doing continual heavy load work.