Do you tow in auto?

[Bulletman]

Gday All,

For those that tow caravans or heavy boats , what/how do you tow.

I have a TDV6 D3 and looking at a 3ton loaded van, so have read tow in auto , don’t tow in auto...sso for those who tow , how do you do it..

Cheers Bulletman

[LGM]

Hello there Bulletman,

We have a 3.2t Avida Topaz 24ft caravan which we tow around the place with our 2011 3.0L D4.

I usually just sit the D4 in the big 'D' and its never complained.

LGM

[shack]

Gday All,

For those that tow caravans or heavy boats , what/how do you tow.

I have a TDV6 D3 and looking at a 3ton loaded van, so have read tow in auto , don’t tow in auto...sso for those who tow , how do you do it..

Cheers BulletmanProbably doesn't make a lot of difference in later models, but I would probably drive in sport mode, engine labours less, and you can easily slip it back a gear when getting ready to overtake/ hit big hills etc.

[shanegtr]

I tow in manual mode in my old D3. If I leave it in auto I often get overboost faults and limp mode on hills when it changes down a gear with decent accelerator input. In manual I can just back off the accelerator slightly when changing down before getting back onto it. Most likely its just the variable vanes on the turbo not responding quickly enough to the increased exhaust flow.

[Bulletman]

Thanks for the inputs, sorry I drive roadtrains with either 3 or 4 trailers so having to leave a gearbox in D is new to me , but I have had the D3 since 2011 and it's what I have so it's going to be used to tow what we buy , so just trying to get the wisdom of those who do/have done what I intend too do.

Cheers Bulletman

[Eric SDV6SE]

I don't think it matters mate, I've towed heavy and light in sport and in D i
the D4. No real difference in the D3 i reckon, except for something to do and watching the fuel gauge. They are both a superb tow vehicle and more than capable in D.

We towed across the country in D, only shifting to S or then into manual if you need to hold a gear. Adelaide Hills was one time and Flinders Ranges, plus coming back into Perth over Kalamunda, but the car could have done it easily in D the whole way.

[BradC]

What is this “auto” of which you speak?
176624

[matti4556]

I tow in "D" with the exception of choosing sport mode for big inclines and manually selecting a lower gear for steep declines. But for general terrain the gearbox is much smarter and quicker than I am.

[Narangga]

What is this “auto” of which you speak?
176624

Brad I believe you have a British import but as it was 26 January on Wednesday, please sing along:

Australian's all let us rejoice
For we have P, N, R and Dee...
176636

:BigThumb:

[John_D4]

Different model, but I have the 8 speed and I’ve played around recently with D or Sports modes when towing. It really hasn’t made much difference to the fuel used or gearbox change points. I haven’t had the opportunity to check the auto temp when in D or S when towing, with the iid yet.

[Dagilmo]

I have an Adventure Off Road camper. In my D3, I towed in S. This was the advice given by a local Indie and I found it was much better than D.

In the D4 I just tow in D. I agree with John, I haven't noticed any difference between S and D.

[veebs]

Is the car aware of the trailer? ie, does the little trailer light come on when signalling?

This seems to tell the gearbox ECU that it needs to adapt, even only a little, for the fact a trailer is behind.

Mind, I have this on a D4, but assume the D3 is exactly the same...

[Dagilmo]

Is the car aware of the trailer? ie, does the little trailer light come on when signalling?

This seems to tell the gearbox ECU that it needs to adapt, even only a little, for the fact a trailer is behind.

Mind, I have this on a D4, but assume the D3 is exactly the same...

If asking me specifically...Yes, both the 3 and the 4 had/have the resistor modification in place.

[p38brickus]

Always use sports and tow in 5th. Works for me. RRS with 25 foot van.176756

[101RRS]

If you tow in Sport how do you stay in 5th - where circumstances are right it will go into 6th.

The reality is that in theory at least you can always tow in 6th - the gearbox responses to engines speed, speed and load to automatically select the correct gear for the circumstance - and it does this well. Where it gets caught out is where overall load hovers around a gear change point where it changes up and down constantly or at a point where the torque converter locks up - same constantly is locking in and out.

In most driving conditions this does not occur and the gearbox is quite capable of handling things in drive. The exceptions are normally long gentle hills or windy hilly country. Going to Sport often helps here where the box hangs onto gears a little longer but on flat runs will go into 6th. In extreme conditions selecting command shift may be more appropriate but I mainly use that when offroad going down steep hills.

So my take is just stay in drive but if you notice what seems to be unnecessary shifts go to Sport where is changes the change points away from what is annoying in the current circumstance.

Garry

[StewG]

I tow a 2.6 Tonne caravan and like others here, have not noticed any difference between D and S. I use D mostly and the paddles when steep and/or winding roads suggest that manual control is better.

[Eric SDV6SE]

I tow a 2.6 Tonne caravan and like others here, have not noticed any difference between D and S. I use D mostly and the paddles when steep and/or winding roads suggest that manual control is better.

It also shows how well the transmission software is set up and how its matched to the engine output in response to changing road conditions.

[BradC]

I'd be interested to know what the general rev range is people see for the 2.7.

I've found much under 2k leads to lugging and high EGT, coolant and oil temps and above 2k doesn't see much benefit.

I *can* tow in 6th, but I get better fuel consumption and lower temperatures in 5th sitting on about 2k rpm.

[rangeyrover]

I'd be interested to know what the general rev range is people see for the 2.7.

I've found much under 2k leads to lugging and high EGT, coolant and oil temps and above 2k doesn't see much benefit.

I *can* tow in 6th, but I get better fuel consumption and lower temperatures in 5th sitting on about 2k rpm.

I normally tow in "S" with a D4 3.0 6 speed and 2000kg van, I prefer the shift points in "S", normally at a GPS106K Speedo 110
I use the manual selection for big grades, up and down hill, especially uphill I find the cruise control will not give a big enough input to maintain speed on a long hill, so right foot intervention required.
Like Brad i have wondered about staying in 5th, I think the box locks in every gear, but I was concerned about burning the clutches (as I'm not sure about the box behaviour) so I haven't done it often.
Any advice about holding 5th would be interesting.

[Wojer]

We have a 2013 D4 towing a 2800Kg van. We have toured around Aus & also live on the east coast and frequently faced with steep inclines & declines.
I normally drive when towing in D, but as others have written, we slip into S for inclines.
I have only found the need to use the paddles on a few occasions when overtaking, especially road trains or needing sudden burst when overtaking on an incline.
The normal drive settings I have found suitable for nearly 99% of situations on a drive.

[Odysseyman]

I think it is worth noting that the Owners Manual for my MY 2016 D4 says, in the Cruise Control section, do NOT use cruise control in Sport mode, for those who may contemplate it. I have no idea why.

When towing my camper I use D and cruise control.

cheers
David

[Eric SDV6SE]

I normally tow in "S" with a D4 3.0 6 speed and 2000kg van, I prefer the shift points in "S", normally at a GPS106K Speedo 110
I use the manual selection for big grades, up and down hill, especially uphill I find the cruise control will not give a big enough input to maintain speed on a long hill, so right foot intervention required.
Like Brad i have wondered about staying in 5th, I think the box locks in every gear, but I was concerned about burning the clutches (as I'm not sure about the box behaviour) so I haven't done it often.
Any advice about holding 5th would be interesting.
Torque converter locks in every gear when engine speed is above 1250rpm. Towing at 100kmh (indicated) in D sees about 1850-1860rpm on my gauges. Average fuel varies with load of course, recent trip to the south west wa saw 13.0 on Forrest highway with camper and 3 people on board ​,EVC controller on U3 and cruise Control on. All temps and pressures steady as a rock, 220,000 km on the odo

[Barraman]

I have towed a 2.5T boat/trailer some 50,000 km over the last 5 years with my 2015 D4 TDV6 8 speed. I have towed in D and S - get slightly better economy in S but I can't say I notice any difference.
I pretty much always use the cruise control. I generally tow on the speed limit.
It mostly tows in 8 or 7 sitting on 1600 rpm at 100 kph in 8 and 1800 in 7. It changes down to 6 for a hill, occasionally 5, rarely lower except for very steep climbs. If it needs to go lower than 5, the cruise control drops out.
I have tried driving on the paddles but find it to be a pain in the bum with a vehicle that tows so easily.
Sitting on 100 kph on a flat road on a 30oC day, the coolant temp sits on 100, the transmission oil temp 95, the sump oil temp 125 and the torque around 250 (max torque about 476), so its not working hard.
It uses on average 17.5 L/100 km towing the boat.
Best towing/cruising vehicle I have ever driven.

[Narangga]

I'd be interested to know what the general rev range is people see for the 2.7.

I've found much under 2k leads to lugging and high EGT, coolant and oil temps and above 2k doesn't see much benefit.

I *can* tow in 6th, but I get better fuel consumption and lower temperatures in 5th sitting on about 2k rpm.

Brad to continue the Australian theme of my posts:

Age shall not weary them, nor the years condemn...

Which is really only to say that I've forgotten the exact RPM my remapped (Roo Systems) 2.7 hits. I also have a Nanocom which does not give an EGT readout, however I have not noticed a change in either coolant or oil temps towing my 1.3T camper in either 6th or 5th. As there is undulating country heading south out of Darwin you have to get past Katherine (300km) before things get reasonably flat. The last decent trip we did was mid-2019 to the Pilbara. So from memory, in 5th it sits around 1975rpm and in 6th around 1685rpm.

If all goes well I'll give you an update in early July after a trip down the Stuart Hwy and return via the Tanami Road and Kununurra.

[scarry]

Sitting on 100 kph on a flat road on a 30oC day, the coolant temp sits on 100, the transmission oil temp 95, the sump oil temp 125 and the torque around 250 (max torque about 476), so its not working hard.
It uses on average 17.5 L/100 km towing the boat.
Best towing/cruising vehicle I have ever driven.

What are the EGT's?
Air temp into engine after intercooler?

Just interested to compare with our umm, non LR.[bighmmm][biggrin]

[BradC]

So from memory, in 5th it sits around 1975rpm and in 6th around 1685rpm.

That sounds about comparable at ~100kph. I notice a significant difference in all temps, but our van is a couple of hundred kilos heavier and probably a lot less aerodynamic (being built on a 1965 Baravan shell).


If all goes well I'll give you an update in early July after a trip down the Stuart Hwy and return via the Tanami Road and Kununurra.

I'll patiently await your update while quietly turning green.

[Narangga]

That sounds about comparable at ~100kph. I notice a significant difference in all temps, but our van is a couple of hundred kilos heavier and probably a lot less aerodynamic (being built on a 1965 Baravan shell).



I'll patiently await your update while quietly turning green.

Oopsie - yes ~ 100kph often around 105 (SOG)

As I remarked to my wife late this afternoon - we should be able to do the trip - unless the Biosecurity Areas in the NT are in force [bigsad]

[Barraman]

What are the EGT's?
Air temp into engine after intercooler?
Just interested to compare with our umm, non LR.[bighmmm][biggrin]

Sorry, I can’t tell you. I’ve never looked at that.

I’ll look the next time I tow the boat - maybe end of the month.

[Pedro_The_Swift]

I have towed a 2.5T boat/trailer some 50,000 km over the last 5 years with my 2015 D4 TDV6 8 speed. I have towed in D and S - get slightly better economy in S but I can't say I notice any difference.
I pretty much always use the cruise control. I generally tow on the speed limit.
It mostly tows in 8 or 7 sitting on 1600 rpm at 100 kph in 8 and 1800 in 7. It changes down to 6 for a hill, occasionally 5, rarely lower except for very steep climbs. If it needs to go lower than 5, the cruise control drops out.
I have tried driving on the paddles but find it to be a pain in the bum with a vehicle that tows so easily.
Sitting on 100 kph on a flat road on a 30oC day, the coolant temp sits on 100, the transmission oil temp 95, the sump oil temp 125 and the torque around 250 (max torque about 476), so its not working hard.
It uses on average 17.5 L/100 km towing the boat.
Best towing/cruising vehicle I have ever driven.

Yep that 8 speed is amazing,
you should try it with the SDV8.. [wink11][biggrin]

[Narangga]

I'd be interested to know what the general rev range is people see for the 2.7.

I've found much under 2k leads to lugging and high EGT, coolant and oil temps and above 2k doesn't see much benefit.

I *can* tow in 6th, but I get better fuel consumption and lower temperatures in 5th sitting on about 2k rpm.

Heading off after lunch tomorrow to Katherine (Gorge) for 2 nights and then heading further south on Tuesday. Thursday will be the first night with reliable mobile reception for internet so I'll post my findings then Brad.

[Narangga]

Heading off after lunch tomorrow to Katherine (Gorge) for 2 nights and then heading further south on Tuesday. Thursday will be the first night with reliable mobile reception for internet so I'll post my findings then Brad.

Firstly the full PDS (Payload Disclosure Statement): Vehicle loaded to 3T with 3/4 roof rack with the sixth wheel bolted to it. Camper weights in at 1.4T (carrying additional liquid gold - aka diesel).

In Sport Mode (S for Speed) @ 100kph by GPS: 5th gear is 2230rpm. If road is level or slightly downhill and cruise control engaged it drops into 6th and is now 1885rpm.

In Drive/Auto (D for Drag) @ 100kph by GPS: 5th gear is 2230rpm. It will ususally drop into 6th by itself and is then 1785rpm. Engaging cruise control on level road will have rpm increase to 1885!

We were also pushing a mainly headwind (with some side component) of 20-30kph too.

I have a Nanocom so am not able to monitor EGT unfortunately. Hope that provides what infor you were after Brad.

[BradC]

Hope that provides what infor you were after Brad.

Absolutely, thanks!

Looks like 5th on the auto is a bit higher than the manual and 6th seems a bit lower. Much of a muchness. Interesting the change in 6th on cruise. I wonder if it unlocks the converter? I can’t figure out what else would account for the change.

[Iherbst87]

If asking me specifically...Yes, both the 3 and the 4 had/have the resistor modification in place.

What is this resistor mod you are talking about? I have heard i need a resistor or load box somewhere to stop my trailer LED lights from pulsing on my 05 D3.

[kelvo]

What is this resistor mod you are talking about? I have heard i need a resistor or load box somewhere to stop my trailer LED lights from pulsing on my 05 D3.
With a D3 you need a ‘pulse buster’ to stop trailer LED lights pulsing. This is basically two resistors and two relays on the trailer indicator circuits. The resistors let the D3 know a trailer is attached, the relays stop the pulsing.

[Iherbst87]

With a D3 you need a ‘pulse buster’ to stop trailer LED lights pulsing. This is basically two resistors and two relays on the trailer indicator circuits. The resistors let the D3 know a trailer is attached, the relays stop the pulsing.

Roga, thank you. That makes sense, will have to look into it a bit more