Towing 19' BT with LC 100 Series Auto

We tow using a Landcruiser 100 turbo diesel, so my comments may or may not apply equally to the petrol Landcruiser.

First question, I guess, is what speed you would expect to cruise at? When we were novice, we used to cruise at about 102-105kmh. Whilst the LC can handle that easily, there is a noticeable increae in fuel consumption compared to the 95kmh which we cruise at now - we have found the more leisurely pace makes for a less stressful trip, and greater enjoyment of the sights.

Now at 95kmh, the LC rolls along the flat easily in normal overdrive (ie normal auto mode). However, we downshift early using the o/drove off button whenever approaching moderate grades as the vehicle will generally lose momentum otherwise on the grade. I should have added that we do use the cruise control facility, and downshifting early is helpful as the cruise control is otherwise a bit slow to kick in its own downshift until it is too late and the speed has already dropped significantly. Also, at a cruising speed of 95kmh, there is a ton of torque immediately available (using the o/drive off) if you need to overtake (eg slow moving truck).

In the case of our vehicle, once you reduce the cruising speed below about 90-92kmh, the cruise control is changing gears so often, that I think you are starting to lose fuel economy depsite the reduction in average travel speed. But others are happy to potter along at 85kmh, so it is very much a matter of personal preference and confidence.

Now, a comment about the cruise control itself - this has been designed to switch off if the speed of the vehicle falls more than 15kmh below the preset. Example, if the cruise control is set at 90kmh, and you are pottering happily up a hill with cruise control on, it will totally cut out once the speed falls to 75kmh. Why Toyota have designed it this way I am not sure, but it is very unnerving the first time it happens to you! However, I have found that if you see the speedo dropping, use the accelerator pedal (even whilst the cruise control is still engaged) and the cruise control will remain engaeged at the preset level once speed is reached again.

Now the question about the 'Power' mode - basically, this makes the cruise control more sensitive to changing gears early (ie the cruise control will down shift earlier in power mode if the vehicle speed starts to drop). This is what you want to happen if you have forgotten to use the o/drive off button to force a dwonshift yourself. We always use the power mode when towing - overall momentum is maintained more consistently - but you will notice that the gearbox is shifting more often and presumably fuel consumption will be higher also.

Now the 'second' button - this is used when starting from rest in, say, severe mud or snow conditions, and forces the vehicle to start in second gear rather than first. The idea being that there is so much power going to the wheels in first gear, that you may initally wheel spin until the vehicle gains momentum whereas in second the engine is working hard, but there is less traction going toi the wheels.

Finally, having said all that, I can understand why some people may prefer to just set and forget the o/drive permanently off when towing - I suspect they pay a higher price in fuel consumption with the higher engine revs. I choose not to drive that way, because our car lumbers along happily in o/drive for most of the time. But again I think there is no right or wrong answer, it depends a lot on personal driving preferences.

Phil

Hi John and Jean,
Just a comment on towing with the L/Cruiser, the down weight on the towball is 350 kg with hitch receiver.Have you ckecked your weight loaded with Gas and Jerry cans full. Must be very close with gear stowed inside as well.Checked my 20ft and found I was slighty overweight and still wanted an outboard motor and fold up trailer as well so that makes over 400kg. Food for thought Had a Nissan Patrol and loved it but not willing to take chances so went with advice and purchased F250. Feel much more confident with extra weight and power. Lot less in the pocket thou but economy is improved as motor is not working as much and feel much safer
Phil and Helen
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John and Jean,

I cannot offer any advice in relation to the 4.5 engine and your proposals to share the running on petrol and gas other than to say towing a 19 footer is likley to be expensive.

In relation to which gear to travel in my expereince has been as follows. Went around the block late last year with 02 L/C TD 5 speed auto towing 18 footer that was between 2.8 to 3 tonne. I found that no matter what the condition we could not get the vehicle to hold overdrive and the slightest undulation would make it drop back so I decided to keep it in 4th.

Consumption varied on what seemed similarly flat roads between 16.5L/100k and 19-20L/100k all in 4th gear. Used cruise control most of the time set at 90-95k.

From other postings here it seems some vehicles can hold overdrive so it may be a try it and see. I suspect the experts would frown upon towing in overdrive but then there are probaly exceptions as there usually is.

Hope this is of some assistance.

Regards, Bill

Hi John and ean,
We tow 18' with diesel 100 series LC no problemo. Have had it stressed to us that if towing 'anything' should NOT be using fifth gear at all or ever. Too much stress. I don't think it matters much what you have when faced with large long upward climb but you are not trying to win any races so what does it matter?
As noted above the faster one goes the more money one needs to spend at the local gas stations along the way.
Prue