Towing 2500kg with 1KD 3.0L engine

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

Hi
I thought I would seek out members thoughts on towing a caravan that is near the 2500kg limit with a 1KD 3.0 diesel engine.

I am a little concerned about towing a 2500kg-loaded van with the possibility of Engine piston failure that is starting to be seen. Engine chipping (not mine) and putting the engine constant load (i.e. towing) seems to be a factor.

I have a 2013 Update GXL Prado, which has travelled 82,000km, towing a 1500kg caravan but only 1400km. at 90 to 95km/hr. depending on conditions.
I have just sold this caravan and have a Tare 2000kg van on order. (up to 2800ATM )

I am not concerned about towing at the 2500kg limit as my model was rated 3000kg in England and New Zealand and later years 3.0L IKD upgraded to 3000kg with little change.
However, I intend to make my Prado cope better by: -
1. Using HR weight distribution system (Toyota recommend -which I have always used),
2.Installing rear air bags (used on my Xtrail previously with success but not a huge fan - don’t intend to upgrade rear coils – see how it goes) and,
3. Thinking about installing a transmission cooler too.

I am just a little concerned about the long-term reliability of the motor rather than being on the 2500kg limit. I do not wish too, but are considering whether I spend the money on my Prado, or just change cars to maybe an Isuzu MUX. I am not convinced the MUX is a better car, although I do not need to worry about being over weight etc.

I am really interested in members thoughts especially if you are towing near 2500kg – how you found it and what modifications you have done etc.
I realise it will be a little underpowered but I can live with that.

Thanks
David

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

Depends where you’ll be travelling.
If on major highways, she’ll be a nuisance, in the way of just about everything.
If out on country roads or the dirt, she’ll be fine, road speeds are more sensible and you can see other vehicles well in advance.
Your only other worry is how long the pistons will hold up. Not on your own though, they can let go in cars test have never towed anything.
I think your model would be a 5-speed auto so you’d tow in 4th. On country roads, it will sing along, converter locked.
Once she sees hills, it will drop out of converter lock and that’s when the trany oil overheats. You could fit a cooler but to me it’ makes more sense to fit a converter lock up kit so the oil doesn’t get hot in the first place.
I fitted a kit to my 2012 and does that thing pull. They take off as per normal when in S mode but at 40kph it will converter lock so I pre select 3. At 40 it grabs licked 3rd and just powers away. Shift up to 4th and you’re done. Can slip her into 5 for down hills or when the going is easy.
Mine also has a reflashed ecu so it handles 2.5t effortlessly.
Of course I’m planning for that day when she does some pistons but in the meantime……
As an aside, I gifted my kid’s 200 series a lock up kit. It pulls a 23’ base station loaded to the max. (needs a GVM upgrade)
Just did the numbers Gladstone South and she returned 13L per 100. Tows everywhere in locked 5, overtakes in locked 4.
Can’t beat 8-pots for towing.

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

Thank you for your thoughts Carco -much appreciated.
David

[Guest Close Guest]

I personally would not even consider embarking on a trip in a 1KD towing now, the amount of engines going bang now is far exceeding the ability to say "It won't happen to me". Saw 2 in last 4 days come back in from Remote SA on tilt trays, both towing and both have lost piston number 3.

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

I forgot, I have bags in the back of mine. It’s lifted 2” with tough dog shocks and springs.
I’m a dead set non believer of WDB’s, I have my theories so I stay with bags.
Incidentally, I towed that van with my old KZ 90. Not as quick as the 150 but got the job done.
She had variable rate rear coils plus bags. The variable rate coils were great.
Good ride when driven as a car and still tough enough when the ball load was added.
I’m sure you’d be disappointed moving to an MUX. Only a viable option if chipped.

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

I personally would not even consider embarking on a trip in a 1KD towing now, the amount of engines going bang now is far exceeding the ability to say "It won't happen to me". Saw 2 in last 4 days come back in from Remote SA on tilt trays, both towing and both have lost piston number 3.

It would be interesting to know what year these cars were as Toyota tried a few new piston designs over the years and if they actually were a little better over time.
Thanks for your reply.
David

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

Nope David. There are no KD’s positively known with upgraded pistons.
The only sure way to have the latest pistons is to buy a new short or long engine.
Toyota didn’t keep track of what pistons went into their last model Prado KD’s.
Sure some scored the 110’s but most got the old 80’s.
Toyota gave up on the KD and concentrated on their problems with the GD.

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

I cracked two pistons, 3 and 4, recently 900km north of Perth while towing, It was a bastard getting the Prado and camper back to Perth, not cheap. I've done a lot of reflecting, and as a mechanical engineer looked into the problem from a technical perspective.

I can share a few lessons that I have learned. I had an early 150 with the original pistons, although the injectors had just been replaced. I also had a Steinbauer chip. I regularlyserviced my Prado. I towed around 2T regularly, and went quite hard, about 30k out of my 170k were towing. After the failure I bought a long motor with the new pistons.

Some thoughts.

• The cracked pistons occur due to a design weakness in the pistons from when they reduced the weight of the pistons to achieve Euro standards.
• Changing injectors, as strongly suggested by some, changes nothing in terms of piston failure.
• Pushing the engine hard with a big load exceeds the capacity of the pistons and they fatigue and eventually fail, it's a straight mechanical failure.
• An easy way to tell how hard the engine is working is by fuel consumption. Anything over 16l/100km average and the engine is working hard.
• Not all engines fail, my mate has gone harder and twice as far without a failure. He didn't have a chip.
• I had been towing hard for about 2 hours when it went bang. There were no obvious warning signs, although I did have a minor change, for about 100km before she went bang the fuel consumption seemed to rise a lot without much extra power.
• Definitely invest in top RAC membership if you are going remote.
• They are a reliable engine provided that you don't flog them.

My new engine came with the latest pistons part number 13101-30200. Some good info on the piston revisions is here. https://toyota-club.net/files/faq/15...piston_eng.htm

As for worrying about it, the tow truck driver who picked us up said that he has seen all the different makes fail.

BTW. I've got a new set of genuine Denso injectors and pipes for sale if anyone is interested

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

Depends where you’ll be travelling.
If on major highways, she’ll be a nuisance, in the way of just about everything.
If out on country roads or the dirt, she’ll be fine, road speeds are more sensible and you can see other vehicles well in advance.
Your only other worry is how long the pistons will hold up. Not on your own though, they can let go in cars test have never towed anything.
I think your model would be a 5-speed auto so you’d tow in 4th. On country roads, it will sing along, converter locked.
Once she sees hills, it will drop out of converter lock and that’s when the trany oil overheats. You could fit a cooler but to me it’ makes more sense to fit a converter lock up kit so the oil doesn’t get hot in the first place.
I fitted a kit to my 2012 and does that thing pull. They take off as per normal when in S mode but at 40kph it will converter lock so I pre select 3. At 40 it grabs licked 3rd and just powers away. Shift up to 4th and you’re done. Can slip her into 5 for down hills or when the going is easy.
Mine also has a reflashed ecu so it handles 2.5t effortlessly.
Of course I’m planning for that day when she does some pistons but in the meantime……
As an aside, I gifted my kid’s 200 series a lock up kit. It pulls a 23’ base station loaded to the max. (needs a GVM upgrade)
Just did the numbers Gladstone South and she returned 13L per 100. Tows everywhere in locked 5, overtakes in locked 4.
Can’t beat 8-pots for towing.

A reflashed ECU is the same as a chip, more power = more force on the pistons. Nothing is bullet proof, my mate has had a lot of engine problems with a late model 200 series, it's luck of the draw.

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

Sad about your pistons but now you’ll have an engine built as she should have come from factory.
Couple of notes.
As an engineer you’d be aware a Steinbauer chip is not the same as a re-flash. The chip simply adds fuel to the existing factory map. Re-flash is run on the dyno and the whole map A/F ratios tuned. Airflow increased to follow up the extra fuel.
Always hard to know how hard an engine is working. Pottering along the Gibb or Bungle Bungles will return very poor consumption but not have her working too hard at all. Trying to maintain highway speeds is usually the worst case, high load and thus high fuel consumption.
You’re spot on with your fuel usage change. When the pistons started to go, compression would have reduced and the injector feedback would have instantly added fuel, trying to restore the lower combustion pressures.
There’s a FB page called Toyota 1KD cracked piston group. Usually a new member daily with that same sad story.
KD engine rebuilders have it down pat now, drive out with a good strong machine.

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

The pistons crack due to mechanical overload, it's a fatigue failure. There is no heat component, both my pistons had a straight mechanical failure. That in turn comes from the amount of repetitive force applied to the top of the piston. Any increase in that force will increase the stress and potentially overload the piston.

A remap still increases force applied to the piston, end of story. I actually chose the Steinbauer because it doesn't change turbo or fuel rail pressure, and because it only adds fuel for a short time before tapering off. I'm pretty sure that this combined with towing was a factor.

The jury is still our on the new pistons. Interestingly the new engine pulls much harder than my old one.

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

Krypto, sorry to hear about your cracked pistons and the angst that goes with it.

What does a new long motor cost fitted?

I wonder if it is cost effective to upgrade to a new Prado which is a safer car for near the price of a long motor, but then you have to replace all your fitted accessories too.?

Do the 2.8 GD Prado's have a more reliable record so far (smaller motor tuned for a bigger output though) ?

Maybe the new 2022/3 Prado will have a bigger motor. (V6?? unlikely as take away from Landcruiser sales?)

David

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

Krypto, sorry to hear about your cracked pistons and the angst that goes with it.

What does a new long motor cost fitted?

I wonder if it is cost effective to upgrade to a new Prado which is a safer car for near the price of a long motor, but then you have to replace all your fitted accessories too.?

Do the 2.8 GD Prado's have a more reliable record so far (smaller motor tuned for a bigger output though) ?

Maybe the new 2022/3 Prado will have a bigger motor. (V6?? unlikely as take away from Landcruiser sales?)

David

The new long motor can be had for around 7k, with injectors. I also bought a new Turbo which meant that I got a Toyota warranty on the lot. I had the manifolds cleaned which were properly sooted up, the EGR is now blocked, so Labour was around 30 hours.

I had the same dilemma as you, I drove the new Prado for a day and I prefer mine with all the extras including the custom valved Ironman suspension.

The problem is not the motor size on the 2.8, all motors are getting smaller with improvements in technology. I would assume that they engineered better pistons, it's a pretty simple structural problem.

Good luck getting a new car anytime soon, two of my mates had their Landcruiser orders cancelled recently pending availability.

[Bluedog16 Member Find all posts View Profile Close Bluedog16]

The new long motor can be had for around 7k, with injectors. I also bought a new Turbo which meant that I got a Toyota warranty on the lot. I had the manifolds cleaned which were properly sooted up, the EGR is now blocked, so Labour was around 30 hours.

I had the same dilemma as you, I drove the new Prado for a day and I prefer mine with all the extras including the custom valved Ironman suspension.

The problem is not the motor size on the 2.8, all motors are getting smaller with improvements in technology. I would assume that they engineered better pistons, it's a pretty simple structural problem.

Good luck getting a new car anytime soon, two of my mates had their Landcruiser orders cancelled recently pending availability.

I thought it would be a lot more for a new long motor.
Would it be fair to say to supply the motor (7K) and have it fitted (removal of old and fitting the new) - ie the TOTAL cost would be around 10K or is this too low?

Could one consider when it is time to replace your injectors (approx $3000?) at 120,000km (my car has done 83,000km) instead, put in a new long motor which comes with new injectors and get the best outcome in cost and durability of the engine??

Thanks David

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

Having gone through this in a lot of detail, don't worry about the injectors unless there is an obvious problem. I bought into the injector BS being peddled online by certain people, and it has nothing to do with cracked pistons, period. The oil starvation due to blocked pickup caused by injector washer failure is a totally different problem.

The cracked piston is due to mechanical overload, exacerbated by increasing torque and power with a chip/remap and/or heavy sustained towing. The pistons weren't up to the job, time will tell whether the new ones are. My long motor has them, it's anyone's guess what pistons your 1KD has. From the info on this page which, seems fairly well researched the crap pistons were manufactured until 2015, the good ones were manufactured from 2013. It is odd that my engine didn't have the latest pistons mentioned on that page, they seem to be for Europe only.

If you did just a long motor you should get away with around 10-11k I would imagine. However, you would also have a running engine to sell for around 3-4k at a guess. I did the turbo and radiator because I intend to keep the old girl, or give her to my son.

I really did tow hard for long periods, as did a mate who's done twice the Kms without problems. If you are easy on your engine I wouldn't be overly worried. Bluedog, what year is your Prado?