I have a 2007 Freelander 2, 2.2 TD4. It's my wife's daily driver and is also the car that we take on holidays towing a Jayco Eagle pop up caravan which has a GVM of about 1850kg.
On rare occasions the engine overheats when towing up steep inclines. We try to avoid the steepest of these but as you can see from the attachment even 15% grades are not uncommon around in Queensland (we did this road yesterday).
Transmission Oil Temperature
To try and get a better view of what is happening even when the dash temperature gauge is showing just below half I did our latest trip with the OBDII plugged in and on live data. My reader is the Autel MaxiAP200. As has been noted here in other threads, the engine oil temp does not read correctly, but it is possible to get accurate live data on both the engine coolant temperature and the transmission oil temperature.
Here is what I saw. When the ambient temp is around 25C, the transmission oil temp gets very quickly up to about 70C and then slowly rises to and seems to stay at between 93 and 100 while negotiating the typical grades found on highways in Australia while traveling between 85 and 100km/h. I have no clue if this is normal. For now, I'm just providing the data. When I come back into town (with stop start and 60km/k) the temperature climbs to 103-105C and when I park with the engine running the temp goes up to 115C until it slowly starts to drop.
Engine Coolant Temperature
The engine coolant temperature is more volatile/regulates itself better . It stays between 85 and 101 depending on acceleration and grade but unlike the Transmission Oil Temperature, it is quite responsive to a rest. The temperature drops quickly going down hill.
I've just come back from our last trip, so wanted to record these numbers while my old brain can remember them. I'll now do some research to see if I am cooking our engine and if there are any mods I should do to improve things while towing and I'll report back here later.
We often go into the mountains with the caravan and I know that the car is getting much hotter than this for brief periods. I don't know at what temp the car actually tells you it's overheating but with the live data we are far more likely to give it a rest, when before we pushed on.
If you have any thoughts on this please let me know.

Click image to enlarge

Not had any data while using my Freelander but towed a big twin axle caravan to south of France and back in temps up to 40° with no issues. Previous Discovery 2 I had a nanocam mounted on the dash while towing. Coolant temps around 100° were normal. I had the electric cooling fan wired to a switch so I could turn it on when it was getting a little hot (Disco had the viscous fan always running as well). Assume you have checked that your electric fan is actually working? Landrover - turning owners into mechanics since 1948

2014 Orkney grey Freelander SD4 GS.
2004 Zambezi silver Discovery 2 Td5 (Gone)
1963 Surf blue Morris Mini Minor Super de Luxe (my little toy)

Hey Bob.
Thanks for your reply. Yes the fans are working. I replaced the motor on the main fan a couple of years back and both fans seem to be working fine. You may have seen another thread I started about fumes in the cabin. I wonder if the fan clicking up to full speed is actually blowing fumes back into the cabin air intake somehow, but that is another issue.

In regards to the engine temperature, I think the transmission oil may be the bigger issue. I got a quote of $750 a few years back to add an inline oil cooler to deal with the towing issue. It might be cheaper in the long run to do this. Stuff I've been reading online this afternoon suggests that letting the temp run at 220f or 105c really limits the life of the oil and the trans.

Matt

My experience, once the coolant temp hits 88 degrees, the transmission temp under load will eventually catch up and mirror the coolant temps within a few degrees. My coolant temps rarely get to 96+ but I recently replaced my rad fans with a Volvo dual fan model. Of course, my engine is the i6.

The transmission cooling is from a heat exchanger that uses the engine coolant. If the transmission gets hot and the engine doesn't then there is a problem with the heat exchanger. If the engine also gets hot then there is a problem with the engine cooling system.

Had real problems with mine at one point, turns out that regular off-roading has baked mud into the radiator and only 30% airflow was possible, solo not a problem, dragging a 1300kg kite up and down the hills of Cornwall and I had to stop to allow her to cool several times to get to our destination. Tried to clean the radiator and she made it home without stopping but the temperature was all over the place.
New radiator and 40C towing the van over the Pyreneese, stupid LR satnav up a mountain towing the van with roads that a mountain goat would have thought twice about - no issue, well apart from the co-pilots words of wisdom. Tangiers Orange - gone, missing her
Replaced by Ewok what a mistake - now a happy Disco Sport owner

Yes thank you both. I noticed that the two temperatures, coolant and trans oil do tend to move in lockstep but as the coolant temperature rises the heat exchanger seems to lose some of its ability to cool the oil. The oil temp then rises a bit further. It makes sense as the heat exchanger is pretty small and the coolant coming into it is already hot.
This is only an issue when towing so I'd prefer to avoid getting a separate radiator for the oil. I wonder if it might make the oil too cool when I am not towing. But it seems to me that the oil and coolant should always equalise because of the heat exchanger. hmmm have to make a decision before I tow the rig to Jindabyne, lockdown permitting. Thanks for your thoughts.

For the real hot climate zones, there is an additional air cooled transmission oil cooler.
Try to source it and install it, it's not so difficult.
Copy the complete link below to your internet explorer address bar and see it.

http://new.lrcat.com/#!/12111/57488/58867/4742

Click image to enlarge

Yes, the coolant temp and tranny temp should be very close, since they share a heat exchanger.

A large difference (after warmup) would indicate a problem. If the tranny temp is much higher, the first thing to try would be reducing the drive load to get drive speed and engine RPM down, and into a lower gear. You'd probably have to be towing a trailer up a hill to overheat the tranny in normal conditions.

I've noticed that slowing down tends to cause coolant temp to go up when climbing hills, so it's a tradeoff.

The tranny fluid is *typically* going to dump heat to the engine coolant, so for that to happen the tranny temp will typically need to be at least slightly higher.

If the tranny is not working hard (very slow speed, coasting downhill?) the coolant might actually heat the tranny fluid. I'm sure that happens during vehicle warmup, since the engine coolant gets hot faster than the tranny.

alex_pescaru wrote:

For the real hot climate zones, there is an additional air cooled transmission oil cooler.
Try to source it and install it, it's not so difficult.
Copy the complete link below to your internet explorer address bar and see it.

http://new.lrcat.com/#!/12111/57488/58867/4742

Click image to enlarge

merlinj79 wrote:

Yes, the coolant temp and tranny temp should be very close, since they share a heat exchanger.

A large difference (after warmup) would indicate a problem. If the tranny temp is much higher, the first thing to try would be reducing the drive load to get drive speed and engine RPM down, and into a lower gear. You'd probably have to be towing a trailer up a hill to overheat the tranny in normal conditions.

I've noticed that slowing down tends to cause coolant temp to go up when climbing hills, so it's a tradeoff.

The tranny fluid is *typically* going to dump heat to the engine coolant, so for that to happen the tranny temp will typically need to be at least slightly higher.

If the tranny is not working hard (very slow speed, coasting downhill?) the coolant might actually heat the tranny fluid. I'm sure that happens during vehicle warmup, since the engine coolant gets hot faster than the tranny.

Earlier Freelanders had one radiator fan & hotter climates got the second smaller fan. So there are some cooling issues under heavy stress.

So an additional transmission cooler seems no surprise. Procrastination, mankind's greatest labour saving device!

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ribama1 wrote:

Click image to enlarge

I finally got the transmission cooler fitted. It was just a matter of taking off the front bumper removing the trans oil heat exchanger lines and replacing them with the ones designed for the cooler ….and then plugging it all in. It isn’t a big job. If I was doing it again I’d consider prefilling the cooler. I felt like I may have been short of tranny fluid for a bit and check the level 3 times in a week.

The cooler makes a huge difference. The temp generally stays at 80 now and recovers quickly after hills. The engine coolant temp gets a little higher than it did before when towing up hill. Yesterday it got to 110 for just a minute but when the downhill starts it takes just seconds to get back to 95 (which is its flat towing temp).

A very good addition for towing, I think, particularly if hilly and towing at the capacity of the fl2.

Good job 👍
Is it specifically for the I6 or would it suit the diesels as well? Landrover - turning owners into mechanics since 1948

2014 Orkney grey Freelander SD4 GS.
2004 Zambezi silver Discovery 2 Td5 (Gone)
1963 Surf blue Morris Mini Minor Super de Luxe (my little toy)

According with his profile and his first post, he owns a diesel...