Towing a 20 foot glass boat

[Hornet Junior Member Find all posts View Profile Close Hornet]

Hey guys,

Got my new 150 GXL, auto, D4D in August 2012, so far, so good.

One question though: what is the appropriate auto transmission selection for towing? When I had my 120 I always towed with it on D. Now, the Manual says to tow on "S"4. But the manual does not specifically address this in terms of explaining when to shift it to S, and should I set and forget on S or should I move to + in any case? When to upshift or downshift? Is it allowed/recommended when towing?
Is it still safe to tow on D?

Also, the manual says the max. speed when towing must be 100 km/h. Is it true? I drive on a freeway ocassionally where the max. speed is 110 km/h.

All the replies would be greatly appreciated.
Cheers

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

Tow it like you stole it ,if it breaks it needed replacing anyway, but only while its under warranty . If it breaks repeatedly then it's not of merchantable quality and you get your money back or a new one . Happy trails kav .

[Hornet Junior Member Find all posts View Profile Close Hornet]

Hi kav, thanks for your reply. I was hoping to get a more technical rather than "general" type of answer.
Still doesn't explain how to tow on S4 though.
I may not drive it "like I stole it" as intending to keep it for at least 4 years.
Cheers

[Hornet Junior Member Find all posts View Profile Close Hornet]

Thanks Jasen, much appreciated.

Keep them coming guys!

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

May be just me but back to back between the 120 and 150 the 150 seems to change up earlier. Part of that will be to keep engine speed down and improve economy. If that is the case then Toyota may be suggesting going to sports mode 4th to keep the revs a bit higher than 5th when the box decides to change itself under low load. Keeping the gearbox in S4 will reduce the number of changes up and down between 4th and 5th. You can try both and see whether the gearbox is hunting in normal automatic mode. If it isn't I reckon it will be fine, if it is changing regularly up and then down and so on use the gearbox in sport mode and only manually change up to 5th on long flat stretches.

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

Tow in S4 with a weighty item such as a large boat. Leaving the auto in 'D' will cause it to hunt between the gears too much.

It can also cause the auto transmission fluid to overheat. From what I have read, some of the diesels are getting too hot by using 'D' only. I have a petrol auto, and tow a van in S4.

The Toyota manual recommends towing in S4 for heavier loads.

S4 will use a bit more fuel. The recommended revs for towing is between 2,000 and 2,500 rpm.

Keep in mind that 'D', or S5 if you use the Selector, is an overdrive gear. S4 is the gear with 1:1 ratio.

The recommended 100k/h towing speed is because trailers/vans can be unstable if not correctly balanced. Saw a boat being towed down your way last year, over the 100 mark on the Hume Highway, the f***wit driving was going too fast. The boat and car were fishtailing over 2 lanes just after he passed me.

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

there is differences in 150 models as far as auto and ecu is concerned, at least my 2010 behaves differently the the 2012.
The 2012 150 changes changes faster, car drives better, less hesitation appears to have more torque earlier. Much easier to overtake in, with the earlier model I often slipped it across to S into 4th, when I wanted to overtake. With this one there seems little benefit, just leave it in D and put the foot down.

I tow a big van, I just slip it across to S and the engine varies the revs as I take off instead of revs staying constant as the torque converter doing the work and then generating more heat. At a hundred km/hr the engine is doing round 2800revs.
If you put it to D it tries to put it in overdrive to drop the revs, but then it loads up with a hill or headwind and then changes between 4th and overdrive, the hunting just generates more heat and isn`t going to do fuel economy any good.
D works ok on the flat with a tailwind.

But I don`t have any issue running the engine with a few more revs on bard, so 4th in S mode is fine by me.
With more revs there is less heat generated in the auto and 2800 rp,m at a 100 in 4th feels better than 2000rpm. In D it would be around 2000rpm engine feels more like its labouring. Try it and see for yourself.
Reality is I sit around 95-98, its comfortable and relaxed for the driver and van, but have towed at a 120km/hr in 4th when overtaking..

[Hornet Junior Member Find all posts View Profile Close Hornet]

Thanks for that guys, much appreciated. I'll try S4 and see for myself. When going uphill or downhill should I leave it in S4?
Cheers

[Hornet Junior Member Find all posts View Profile Close Hornet]

If I tow on D, it feels gutless.

I plant the foot down and it feels that the car just maitains the same speed, feels really gutless.

Cannot overtake on D as the car does not accelerate or does it too slow especially when compared to my previous 120.

So, are you recommending to shift from D to S4 if I need to overtake and then shift it back to D?

Cheers

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

If I tow on D, it feels gutless.

I plant the foot down and it feels that the car just maitains the same speed, feels really gutless.

Cannot overtake on D as the car does not accelerate or does it too slow especially when compared to my previous 120.

So, are you recommending to shift from D to S4 if I need to overtake and then shift it back to D?

Cheers

nah just put foot down harder.

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

Logic says that you slam your foot down hard and it will go as hard as it can but Logic does not work for Toyota (although this will work on the V6). I do not have a chip and I have noticed that if you give the accelerator a little to get off the mark and then progressively get into it say over a couple of seconds the Prado surges ahead. Just stamp on it and you seem to sit there for an extra smoko break before you seriously get moving. Back on subject, I tow 2100kg van in S4 and go to S5 on downhill runs. Normally running on cruise control and foot control going uphill if the boost is getting close to kickdown. I then hold the boost at around 11psi on the Scanguage and let the speed come of a little as required. Never overheated the trans towing and get 13 - 14 LPH. Very happy with that, wish I could tow it around all the time.

[Hornet Junior Member Find all posts View Profile Close Hornet]

Thanks guys, towing to Nelson in a few weeks time, will see how it goes on S4.

Cheers,

[okkanui Lurker Find all posts View Profile Close okkanui]

I have a 2010 150 VX petrol that is bog standard, and regularly tow my 2 tonne boat/trailer all around Victoria. I also do trips up to south coast of NSW, which takes us over some pretty hilly territory (especially around Eden). I just stick it in D and let the auto work out the best gear it needs to be in. I would typically sit on 100kmh when on highway (if safe to do so) and the auto usually stays in D5 (except if hill).

[nevh Lurker Find all posts View Profile Close nevh]

Just fitted a Scangauge to my late 2011 Diesel auto mainly because I tow a 2.5 T van and want to keep a check on the AutoTrans. temp. Just driving around town in traffic (not towing) Scangauge reads a touch over 100 degrees C. Does anyone know at what Temp. the Auto hot light is factory set at.

[A10 Member Find all posts View Profile Close A10]

Just fitted a Scangauge to my late 2011 Diesel auto mainly because I tow a 2.5 T van and want to keep a check on the AutoTrans. temp. Just driving around town in traffic (not towing) Scangauge reads a touch over 100 degrees C. Does anyone know at what Temp. the Auto hot light is factory set at.

Supposedly 150 degrees C.