Towing 2500kg with 1KD 3.0L engine

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

Hi Krypto,
My car is a Sept 2013 (new Update) build. I believe a new design piston was installed officially Jan. 2014 for the Update model. Hoping the new pistons may have been installed a little earlier and in my car. The new coated injectors have been found much earlier than the offical install date so you never know.
Thanks David

[kizbot Member Find all posts View Profile Close kizbot]

Krypto, do you mind me asking if you always towed in 4th gear? We keep getting told to tow in 4th to cool the engine and save the transmission but increased RPM = more force on the pistons correct? 4th at a slower speed might be a good compromise. Hard to do on Australian highways.

[carco Advanced Member Find all posts View Profile Close carco]

Blue dog don’t waste time listening to the 2013, 2014, 2015 etc etc sales pitch from Toyota. Go straight to D4D engines.com.au.
You’ll get the true picture as they pull these things down daily.
There’s no magic cut off date for upgraded pistons, it was just luck of the draw. Or rather whatever pistons were in the assembly bin on a particular day.
Likewise the rubbish about injectors. Can’t believe it took so long for seemingly intelligent mechanics to work out the process of piston failure leading to lower cylinder pressure leading to max injector feedback. For years they had it arse about!

Kizbot we tow in 4th as that will give the most usable road speed with converter locked. Depending on accelerator position, anywhere from around 75 to 100+
Mine converter locks at 70 (load dependent)
Tow in D and it won’t converter lock until around 80 at minimal load. Add some towing load and it will be much higher. And of course give it a hill and it will drop straight out of converter lock and try to pull in 5th unlocked. More load and it will drop to 4th unlocked then quickly flare back to locked 4th. More load and it will drop out of locked 4, etc, etc.
Poor thing will be locking / unlocking and generally getting nowhere.

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

Krypto, do you mind me asking if you always towed in 4th gear? We keep getting told to tow in 4th to cool the engine and save the transmission but increased RPM = more force on the pistons correct? 4th at a slower speed might be a good compromise. Hard to do on Australian highways.

I always tow in 4th. The faster the engine revs for a given speed, the less force per piston stroke. If you think about riding a bike, the higher the gear the harder it is to pedal for a given speed.

So towing in a lower gear puts less strain on the engine, and most parts of the gearbox.

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

Blue dog don’t waste time listening to the 2013, 2014, 2015 etc etc sales pitch from Toyota. Go straight to D4D engines.com.au.
You’ll get the true picture as they pull these things down daily.
There’s no magic cut off date for upgraded pistons, it was just luck of the draw. Or rather whatever pistons were in the assembly bin on a particular day.
Likewise the rubbish about injectors. Can’t believe it took so long for seemingly intelligent mechanics to work out the process of piston failure leading to lower cylinder pressure leading to max injector feedback. For years they had it arse about!

Kizbot we tow in 4th as that will give the most usable road speed with converter locked. Depending on accelerator position, anywhere from around 75 to 100+
Mine converter locks at 70 (load dependent)
Tow in D and it won’t converter lock until around 80 at minimal load. Add some towing load and it will be much higher. And of course give it a hill and it will drop straight out of converter lock and try to pull in 5th unlocked. More load and it will drop to 4th unlocked then quickly flare back to locked 4th. More load and it will drop out of locked 4, etc, etc.
Poor thing will be locking / unlocking and generally getting nowhere.

Spot on about the injectors. If you want a really simple explanation of the injector problem have a look at this, no waahing on like some other pundits. https://www.youtube.com/watch?v=O5oe-vtrOUU

Forcing a gearbox to lock can have some unintended side effects in overloading certain parts of the gearbox. There is a reason that the people who designed the gearbox chose the forces at which the gearbox should unlock. That's not to say forcing lock up is a bad thing, but it's something to be aware of

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

Another consideration -should we be fitting a transmission cooler?
I haven't towed a lot with my Prado yet, only with a 1500kg very low pop top but always in 4th gear. My scan gauge showed the auto temperature to stay around 90+ on a hot day.
As I intend towing a full size 2500kg van will I need to fit a transmission cooler or will towing in 4th still keep the temperatures reasonable. (40+ degree days would raise it)
If you have a transmission cooler fitted would you now say it is essential, worthwhile or not made much difference if towing in 4th?

Also I am thinking on fitting rear air bags with the kevlar sheath as my ball weight will be up to 250kg. I do use a HR weight distribution distribution system and will have a DO35+ fitted on my new van.
If you have air bags fitted do you use a weight distribution system as well? I realise they do different things- WDH transfers the load to front wheels, while air bags only level rear of car.

Thanks
David

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

I fitted a transmission cooler very early on as the transmission regularly exceeds 100C without it. That temperature is at the limits of the oil and not good for seals etc. I fitted the biggest cooler that I could and it lowers the temp by about 15-20C.

I also change the transmission oil every 50k by which time it is usually starting to discolour with a slight brown tinge and hence starting to lose some of it's properties. I can't believe that they say it's a sealed for life gearbox given how hard it works

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

I use airbags and heavy duty springs. Fitted the group buy Ironman suspension from here a few years ago, brilliant!

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

I fitted a transmission cooler very early on as the transmission regularly exceeds 100C without it. That temperature is at the limits of the oil and not good for seals etc. I fitted the biggest cooler that I could and it lowers the temp by about 15-20C.

I also change the transmission oil every 50k by which time it is usually starting to discolour with a slight brown tinge and hence starting to lose some of it's properties. I can't believe that they say it's a sealed for life gearbox given how hard it works

Thanks Krypto - some good information.

I am considering fitting a 'Wholesale Automatic' transmission cooler and will change the transmission fluid at the same time. Prefer to only change the oil rather than get a service and risk the pan/gaskets leaking etc. or is that foolish? (travelled 83,000km with only 1400km of it towing a light caravan)

David

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

They don't remove the pan to change the oil. I did get mine flushed once, worth doing if you've never had it changed. Shouldn't cost much.

[TerryO Moderated member Find all posts View Profile Close TerryO]

I have a 2014 Kakadu with 196,000km on the clock, around 18000 of that towing a 2500kg caravan. I am currently on a trip from the Sunshine Coast to Mount Isa and back. On Monday we were 3km outside Cloncurry when we experienced a loss of power and I observed a cloud of smoke from the exhaust. The vehicle has been checked and I am up for a new short engine and new injectors. I have now been told that failure of the 3L engine is not uncommon. I am now stuck in Mount Isa waiting for a new engine, repair cost on the high side of $16k. Apparently number 4 injector failed and blew a hole in the piston. I had noted an increase in fuel consumption lately but put that down to the environment. I do not work the car hard, the van is not overloaded and we generally travel at ~90km/h. This is my second Prado, I had over 300k on the Grande and never had any trouble. Does anyone know if this failure can be considered "not fit for purpose" so I can have a go at recouping some of the cost.

[krypto Avid PP Poster! Find all posts View Profile Close krypto]

More than likely it is a cracked piston, I had exactly the same scenario just recently except North of WA towing a camper. An injector doesn't blow a hole in the piston.

I doubt that there is any recourse against Toyota. I got a new Toyota long engine with injectors and new turbo installed by Toyota with warranty for 16k.

[money_killer Member Find all posts View Profile Close money_killer]

i have the same set up found it to under powered. was going to sell and get a v8 crusier but instead went for a ecu remap 20% safe tune on the dyno for $1600 total different car. no need to upgrade

[Guest Close Guest]

i have the same set up found it to under powered. was going to sell and get a v8 crusier but instead went for a ecu remap 20% safe tune on the dyno for $1600 total different car. no need to upgrade

No tune or towing is safe on the 1KD motor.. Well known they eat pistons at any moment when tuned, and even quicker when towing sadly.. they are just not cut out for what they are doing. Got two prados, 2009 and 2013 sitting in the mechanics yard next door, both cracked no 3 piston. one tuned, and both were towing.

[money_killer Member Find all posts View Profile Close money_killer]

No tune or towing is safe on the 1KD motor.. Well known they eat pistons at any moment when tuned, and even quicker when towing sadly.. they are just not cut out for what they are doing. Got two prados, 2009 and 2013 sitting in the mechanics yard next door, both cracked no 3 piston. one tuned, and both were towing.

Guess time will time