Transmission temperature A750F auto

[HK1837]

Haven't been on sand for a lot of years, probably last time was in my old HZ Holden Overlander tonner.

So took my 2011 V6 auto SR5 on Stockton beach this morning scoping out some spots for night photography. My SR5 has power and torque in abundance (175kW+ and 600nM at back wheels). I have a transmission temperature gauge fitted (Wholesale autos). Toyo AT2's at 17psi, car drove anywhere with ease in 4H, easily cruising around below 2000rpm at 40km/h, probably 3rd gear. However the transmission temperature climbed very quickly approaching 120degC. It has a large auto transmission cooler fitted too. So I stopped and ran it in 4L, engine worked harder (running around 3000rpm at 40km/h, not sure what gear) but temperature dropped and stayed around 90degC. It was easier driving in 4H but better on the transmission in 4L.
So I can only imagine anyone beach driving with an auto without an external cooler must be seeing excessive auto transmission temperatures. I was surprised how quickly it rose, despite the ambient probably below 12-13deg. It must be the torque converter is not working as hard in 4L.

[Gipsy]

Try manually selecting a lower gear in h4 and allow the revs to keep it cool. even v6 don't like lugging if you can avoid it.

[taresk]

I never use Drive in the sand, always put it in the gear I want to use, It's a pretty smooth auto and is likely shuffling gears more than you realise.

If it still gets hot, maybe consider a manual lock-up kit to stop the torque converter cutting in and out.