Thread: TD5 Auto towing a 2.4tonne caravan

My thoughts are:
EGT gauge - so you dont accidentally do the motor from high EGTs
Additional ATF cooler - because you will end up cooking the transmission.

This one:
Aux Transmission Oil Cooler | MODIFICATION | Davis Performance

'03 series 2A, TD5, Auto, EGR block off, ECU Remap from Alive Tuning UK, boost up to 18-19psi, decat pipe, hi flow centre muffler).

Hey guys,

I'm about to start towing a 2.4tonne caravan around.

I hired one out at the same weight and it did an ok job on that single trip, from Brissy to Ballina.

I'm just wondering if I start towing more often, what the potential problems I'm going to start running into are and how to reduce the chances of those things happening and hot to properly monitor the situation, especially considering I plan on pulling the caravan on the beach.

I haven't got the temp alarm installed or any gauges.

I know how to drive with a caravan attached, to reduce the load on the disco - eg, crusing on 85-90 not 100, carrying momentum into the hills, using just enough throttle to get to the top of hill and letting it cruise down etc (traffic behind me isn't a concern, the well being of my vehicle and fuel economy is, as selfish as that sounds).

Happy to hear any suggestions & advice, especially what mods and where to go to get any suggested mods. I'm in Brisbane.

TIA guys.

1 Get an EGT gauge. I only tow about 900Kg but my EGTs can go over 700C easily and if you have a chip this is probably inevitable. I found going up the hill climbing out from the Hawkesbury bridge North that I had to drop back to third with very light throttle when towing my daughter's heavier say 1400Kg camper trailer.

2 don't even think about using cruise control when towing as it will ram the throttle wide open on the slightest hill . (see EGTs)

3 get a bigger intercooler. I have a Serck.

4 try to remain in transmission lockup as much as possible by running in third to 70KMh letting it lock up, then running to 80KMH in third lockup , then changing to 4th when it will lock up in 4th. If you see a big hill or one with curves, drop to 3rd early so lock up remains in down to 50Kmh.

5 I don't like running in sport as the lock ups are delayed , so IMHO run in normal. There are differing opinions on this, but I tried it with the heavier camper trailer and the lock up was delayed

6 make sure your Radiator is in perfect condition and your auxiliary fan is working correctly and radiator hoses are good including the "secret Hose".

7 I add the required dose of Redline Water Wetter to my radiator to ensure optimum cooling.

8 either add an additional cooler to your transmission and/or run Castrol Transmax Z in the transmission. Castrol Transmax Z is a full synthetic high quality fluid which claims to run the transmission 20C cooler and is formally approved by ZF. you will either have to get a full flush or do maybe 2 to 3 changes .(expensive but cheap compared to a transmission)

9 check that you transmission cooler pipes are in good condition, especially the "hot" pipe on the LH. The point of failure is the swage where the steel pipe meets the rubber hose. if it is on any angle or weeping replace it or both.


You really have not tested your rig going from Brisbane to Ballina as there are basically no big climbs. I recommend you try maybe going to Toowoomba. You are going to have to climb at some stage as it is impossible to avoid long climbs somewhere on the East Coast.
Regards PhilipA
No Big tyres keep to maybe 245.70R16 max. These are readily available compared to 235.70R16 or even 205R16 as these are the same diameter as the 235s. Bigger tyres will increase EGTs.

How many k’s has the transmission done?

Have merged both threads so the other reply is here too now. 👍

Originally Posted by Slunnie

My thoughts are:
EGT gauge - so you dont accidentally do the motor from high EGTs
Additional ATF cooler - because you will end up cooking the transmission.

This one:
Aux Transmission Oil Cooler | MODIFICATION | Davis Performance

X100, especially the bit about the ATF cooler. I'd even consider a winged transmission sump. The trans simply does not carry enough oil to cool, in Oz temps, towing anything bigger than a box trailer. The car is a brilliant tow vehicle, but the auto needs help. It was designed for things like 5 or 7 series Beemers. 1000 ks towing this killed mine. Bit heavier than your van, sure, but it was only once.
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