Engine shutdown when auto is overloaded ?

[Zukjeff Lurker Find all posts View Profile Close Zukjeff]

At a meeting last night I was told that a off road driver trainer is sh!t canning the Diesel Auto Prado as being VERY dangerous.
He repeatedly demonstrated that he could make the engine shut down while in a 40 to 45* hill by overloading the auto.
They would drive up or down a 40 to 45* hill , stop, letting the Prado do its hill hold , then select the other direction and give it some right foot.
Each time the vehicle would load up then shut down the engine and let go of the auto. the vehicle would then drop at full rolling speed to the base of a hill. You had no power steering and only 1 application of the breaks after the engine stopped.
The trainer said he shows this 'fault' on any auto Prado.
I was not at the training day but several members were and were so spooked that they have asked that NO Autos be purchased by our organisation in the future.

I assume it was a GXL.

I assume many of the hardcore fellas here must have had this happen ( if it is a problem) unless the trainer was using the vehicle incorrectly ?

[D4D Addicted PP Member Find all posts View Profile Close D4D]

Re: Engine shutdown when auto is overloaded ?

letting the Prado do its hill hold

Sounds like the instructor should himself learn proper hill start/stop technique. I always use a combination of handbrake and footbrake as you're supposed to and never put the auto into park on a hill. That said I've never experienced this 'phenomenon'

[leachy_9 Advanced Member Find all posts View Profile Close leachy_9]

Re: Engine shutdown when auto is overloaded ?

Any vehicle whether Auto or Manaul will fail if abused and/or used incorrectly.
I too have never experienced or heard of this issue but even if it is possible to induce this type of engine shut down it sounds like it is the result driver error.

Leachy

[Guest Close Guest]

Re: Engine shutdown when auto is overloaded ?

Sounds like improper techniques to me (if its true).

Oddly enough i was on such a hill (up/down) on weekend and was stopping and doing normal (safe) takeoff and recovery techniques, not once did this happen.. So am I doing it wrong :lol:
And I had a 4wd trainer of 15 yrs experience in the back (along for the ride as he is a mate...) Maybe he doesnt know what he is doing either.. :cry:

[Hutch Addicted PP Member Find all posts View Profile Close Hutch]

Re: Engine shutdown when auto is overloaded ?

Out of curiousity what was this driver trainer driving himself??

[MickL Addicted PP Member Find all posts View Profile Close MickL]

Re: Engine shutdown when auto is overloaded ?

What sort of instructor demonstrates the wrong procedure (in this case a stall start) and then blames the vehicle when it fails?

Where did this guy get his driver traning accreditation?

You mention a few things that stood out so I have a theory on how he made this happen.

The angle...40-45 degrees... the Prado has a maximum negotiable angle of 42 degrees (in the ball park of what most 4wds do). So the Prado is at or near it's max climb angle.
Next is the fact it's a diesel... which means it has a low oil level switch (as most if not all diesel engines do).... and lastly at the change of direction "Gave it some right foot" I imagine ment he wasn't being gentle...

So combine these things and I imagine it's possible to swish the sump oil around enough to cut the engine out via the sump level switch. BUT we are talking about a vehicle that is right at the limits of its mechanical abilities and then basically abused. The same could be done then with any make of vehicle in the same situation.

Just a theory and one that would also hold true of manual trans vehicles.

Just for the record: 40 to 45 degrees is pretty steep (those travel ramps you see at 4wd show are 30 degrees and their pretty steep...45 degrees is bloody hard to walk up let alone drive :!: )

If you're driving that sort of terrain there's no just stopping at changing direction... it's straight up or straight down in LL. If you have to stop then you need to stall the vehicle and do a correct stall recovery which is the point of doing driver training... to learn the correct procedure...not watch a so called instructor fool around. :roll:

Also for the record... never had it happen...seen it happen... or until this post...heard of it happening.

Mick

[mjforder Senior Member Find all posts View Profile Close mjforder]

Re: Engine shutdown when auto is overloaded ?

What sort of instructor demonstrates the wrong procedure (in this case a stall start) and then blames the vehicle when it fails?

Where did this guy get his driver traning accreditation?

You mention a few things that stood out so I have a theory on how he made this happen.

The angle...40-45 degrees... the Prado has a maximum negotiable angle of 42 degrees (in the ball park of what most 4wds do). So the Prado is at or near it's max climb angle.
Next is the fact it's a diesel... which means it has a low oil level switch (as most if not all diesel engines do).... and lastly at the change of direction "Gave it some right foot" I imagine ment he wasn't being gentle...

So combine these things and I imagine it's possible to swish the sump oil around enough to cut the engine out via the sump level switch. BUT we are talking about a vehicle that is right at the limits of its mechanical abilities and then basically abused. The same could be done then with any make of vehicle in the same situation.

Just a theory and one that would also hold true of manual trans vehicles.

Just for the record: 40 to 45 degrees is pretty steep (those travel ramps you see at 4wd show are 30 degrees and their pretty steep...45 degrees is bloody hard to walk up let alone drive :!: )

If you're driving that sort of terrain there's no just stopping at changing direction... it's straight up or straight down in LL. If you have to stop then you need to stall the vehicle and do a correct stall recovery which is the point of doing driver training... to learn the correct procedure...not watch a so called instructor fool around. :roll:

Also for the record... never had it happen...seen it happen... or until this post...heard of it happening.

Mick

Mick - fair point. AND that's where monster trucks take over from a Prado........you cant always have your cake and eat it to.....something has to give eventually.

I recently had some fun time (again) at Morgan....and everyone chickened out apart from me and i did this hill......now aptly renamed difflocker hill. i reckon the car was inclined at least 40 deg front/back AND left/right.....not bad for a car that you can buy from a showroom and spend a few $'s to mod.

and the car can tow a ski boat or a camper and take the family to a picnic etc......



M

[IRON-PAWW Avid PP Poster! Find all posts View Profile Close IRON-PAWW]

Re: Engine shutdown when auto is overloaded ?

What, I wonder, were the instructors motives for running up to the nearest Prado and showing his ability to shut it down on a 45 degree slope? I suppose I can understand an instructor saying don't do this with Diesel automatics. And don't be an idiot and try this at home. There's no better way to drive a point home than a real demonstration, the 4WD school should use their own Prado to demonstrate it though. If they did that with my Prado then I'd be less than impressed. I suppose people need to see the limits of their machinery to get an idea of what might be pushing things a bit. As long as it's explained fully and people walk away vowing never to try that stunt.

If the 4WD school demonstrated that to promote Nissans and Diss Prado's then they can find the nearest lavapit and take a bath.

[MickL Addicted PP Member Find all posts View Profile Close MickL]

Re: Engine shutdown when auto is overloaded ?

If the 4WD school demonstrated that to promote Nissans and Diss Prado's then they can find the nearest lavapit and take a bath.

I think you hit the nail on the head....


Mick

[Bushbasher Out of control poster! Find all posts View Profile Close Bushbasher]

Re: Engine shutdown when auto is overloaded ?

As an owner of a D4D auto Prado, and a 4WD instructor for my govt department, I show the trainees the abilities and differences with all types of vehicles: autos, manuals, diesels, petrol, straight 4, straight 6, V6, V8, turbo, non turbo.

Never have I demonstrated what not to do. I try to instil the knowledge that all have some very capable characteristics and they need to appreciate what the vehicles can do. I point out some dangerous things to avoid - like using a kangaroo jack to change a tyre. We do the full recovery training using winches and snatch straps as well.

We often climb the stopes of open-cut mines. These are great for stall recoveries. The autos surprise everyone as much as the smaller Rodeos. All these vehicles have limitations.

After 10 years of driving my own manual petrol V6 Prado, my new 09 GXL auto t/diesel is simply a fantastic machine to drive off road. I've just spent 2 weeks driving through the slop out east of Wiluna following some recent heavy rain and this car simply cruised through the thick of it. Mind you, it has taken 3 days to get rid of the mud and dust from the car! But it was well worth it.