towing in overdrive

Coxy45 · Veteran Member

towing in overdrive

magraret · Senior Member

hi all this may seem a silly question but using a nisson ST 2011 with a 19.6 caravan we dont use cruise control but do use over drive is this ok or are we driving wrong

gold dandelion · Senior Member

i agree, we hardly ever use it towing unless we have a tail wind or down hill.

ozjohn · Guru

The same applies to an Auto.
When towing the Torque Converter should be locked.
Towing in Overdrive will cause the Torque Converter to continually unlock (And slip) and then relock depending on the terrain and winds etc.
This slippage when unlocked causes the transission to overheat and thus increases wear.
Ozjohn

billeeeeeee · Guru

Howdyeeeee all u Nomatice Nomads ,Nutters ect ect, WOT!!! if u got a auto box ,and it keeps going into over drive, wot then ,???? should i ignore the computer, and keep it in 5th gear,,???? stay excited ............Billeeeeeee

Pete in Gisborne · Veteran Member

billeeeeeee wrote:
Howdyeeeee all u Nomatice Nomads ,Nutters ect ect, WOT!!! if u got a auto box ,and it keeps going into over drive, wot then ,???? should i ignore the computer, and keep it in 5th gear,,???? stay excited ............Billeeeeeee

Dusent yor werdproceser have a spel cheker on it Billeeeeeeeeeeeeeeeeeeeeeeeeeeee biggrin

pricey43 · Guru

While we were in Alice this year. The newbie opposite us had just towed his new van from Adelaide up with his Nissan patrol.

He had been towing in 5th.

He spent an extra week in Alice waiting for the reco gearbox to arrive and be installed and left with strict instructions to stay in 4th while towing.

Here endeth the lesson. !!!!! disbelief

blaze · Guru

ozjohn wrote:
The same applies to an Auto.
When towing the Torque Converter should be locked.
Towing in Overdrive will cause the Torque Converter to continually unlock (And slip) and then relock depending on the terrain and winds etc.
This slippage when unlocked causes the transission to overheat and thus increases wear.
Ozjohn

Not intirely correct Ozjohn. Most if not all modern auto gearboxs lockup in most or all the ranges. The computer control system controls the engine/ transmission to give the best outcome. So for a modern outo trans I sugest selecting drive, if you encounter very warm days (+35 degrees) and/or strong winds then select 3rd and take it a little easier. We struck 41 degrees yesterday with strong crosswinds which seens us in 3rd for the last 60km of a 560km day. Auto trans oil can run upto 140 degrees before starting to airate and degenerate and most modern auto trans will give a warning of somesort at 125 degree

cheers

blaze

billeeeeeee · Guru

Pete in Gisborne wrote:
billeeeeeee wrote:
Howdyeeeee all u Nomatice Nomads ,Nutters ect ect, WOT!!! if u got a auto box ,and it keeps going into over drive, wot then ,???? should i ignore the computer, and keep it in 5th gear,,???? stay excited ............Billeeeeeee
Dusent yor werdproceser have a spel cheker on it Billeeeeeeeeeeeeeeeeeeeeeeeeeeee

Awww Shucks, peteeeee boy............u b sure to stay excited....................Billeeeeeee

rockylizard · Guru

gold dandelion wrote:
i agree, we hardly ever use it towing unless we have a tail wind or down hill.
--ALSO--
blaze wrote:
ozjohn wrote:
The same applies to an Auto.
When towing the Torque Converter should be locked.
Towing in Overdrive will cause the Torque Converter to continually unlock (And slip) and then relock depending on the terrain and winds etc.
This slippage when unlocked causes the transission to overheat and thus increases wear.
Ozjohn
Not intirely correct Ozjohn. Most if not all modern auto gearboxs lockup in most or all the ranges. The computer control system controls the engine/ transmission to give the best outcome. So for a modern outo trans I sugest selecting drive, if you encounter very warm days (+35 degrees) and/or strong winds then select 3rd and take it a little easier. We struck 41 degrees yesterday with strong crosswinds which seens us in 3rd for the last 60km of a 560km day. Auto trans oil can run upto 140 degrees before starting to airate and degenerate and most modern auto trans will give a warning of somesort at 125 degree
cheers
blaze

Gday...

Generally speaking, I agree manual boxes should not use 5th (overdrive) for towing. Unless you are VERY disciplined and ALWAYS change down early for hills etc and use the tacho to ensure you do not labour the motor and gearbox.

However, modern auto boxes are a long way from the boxes of a decade ago. My book states to use "D" for towing and to let the computers (engine and transmission) to determine load, roadspeed etc etc to decide which gear suits the vehicle most. Works perfectly. If not in "D", then I am to use Sportmatic feature in hilly country, which holds gears a bit longer. In fact the ZF gearbox in my vehicle does not have a 1:1 gear ... 4th is an intermediate gear and 5th and 6th are overdrives. My auto box rarely chooses to use 6th when towing.

And regarding the suggestion of only using 5th (overdrive in a 5-speed box) down hill I would think could become a little unsafe. You really need the engine braking down hill to maintain stability on the tug and van - if you drop into 5th (overdrive) from 4th (1:1 gear) you have the potential to allow a "run away" situation - and the potential for an overuse of brakes. You could even create a worse 'run away' coz when ya hit the clutch to go back to 4th - the whole rig is coasting for that amount of time - and by the time ya got 4th, ya probably should have gone to 3rd to control the whole thing .... best to leave it in 4th down hills please (or lower gear if steep hill).

[sorry - that sounds a bit like a lecture ]

cheers - John

aussietraveller · Guru

This issue has been argued many times in the past, I have a modern auto box and with testing in similar terrain over an extended period of time I have found that I get better economy when towing in 4th gear rather than drive and as previously mentioned better down hill control due to engine braking, economy improves by about 55-60 klm per tank and on gas that's reasonable I usually cruise at around 90 kph

justcruisin01 · Guru

It seems there is a lot to be said for an old manual heavy duty system, no computors, no auto's just the ability of the driver to sort it all out.

My old tug has done 360,000kls, over 200,000kls would have been towing a van &/or a off road H/D camper & often carring a boat as well. Use 5th all the time & it performs better than in fourth as it sits right in the torque zone. Can't complain about that.

JC.

Scotty01 · Senior Member

After refering a few of my clients ( I am a motor Mechanic ) to a very good Auto Trans specialist for trans failure. When I spoke to him he informed me that ALL late model electronic auto's should be drived with OD switched off ( most have a switch to do this ) in city driving and should remain off untill travelling at min of 80kph on highways. When towing he recomends OD remains OFF except when cruising at over 80kph on flat road. In hilly terain or in the mountains OD should remain OFF at all times.

rockylizard · Guru

Gday...

That's interesting - my auto will not go allow 6th overdrive under 90kph (whether towing or not towing) and will not change up to 5th (which is also an overdrive) below 80kph - again whether towing or not towing. The auto is programmed that way - there are no buttons to 'override' the computer.

Cheers - John

Clemoposs · Newbie

I am currently sitting in a caravan park in Kununurra waiting for my auto transmission to be re-built. Been here 3 weeks now. Was driving my Nissan GU 2003 3l diesel automatic. Broke down at Turkey Creek. Had been driving in overdrive through the minor hills and rises between Kununurra and Turkey Creek and the transmission was automatically shifting from O/D to forth and third. My wife commented on the heat coming off the trans tunnel between the seats three times and not long after that the transmission failed. I was towing a 2.6 ton van. My advice is that you DO NOT tow in overdrive in an auto patrol. You will get away with it for a while but will ultimately pay the price. Switch the overdrive off and then allow the trans to auto select. As for me, I'm buying a Landcruiser.

brickies · Guru

Had my 2008 desiel prado auto services last week which I do yearly , the guy told me lots of people ignore their auto transmission he said once the oil is no longer red it time to change it , When towing stay in 4 th gear in auto till you reach 90 kph then pop into drive , And when you see a rise ahead drop back to 4 th ., The main thing is to have good clean oil in your auto box .

Aus-Kiwi · Guru

Can't beat a good trans cooler .. Not all vehicles are the same . The mechanics at 80 mile beach is making a great living replacing auto's . Turbo Diesel engines tend to build boost and power at very low rpm . It still puts load on everything .. Modern vehicles are set up for fuel efficiency which doesn't cover hauling 2 ton van ..

JackoFJR · Senior Member

Fit a trans temp gauge and keep a eye on it

iana · Guru

It would be good if on this web site, this information was collated into one document relating to each type of vehicle. What is said on here may be applicable to some vehicles and not others. It would make a helpful section for us all to refer to.

Ron-D · Guru

Yeah five speed auto ,with my car I usually drive it locked in 4th you can hear the things running smooth as silk not labouring at all,with auto on while towing it has a tendency to change into drive to often and you can then hear it labouring not good eh!

There's a massive difference when towing with in auto unhitched ,compared to driving without a couple of ton hooked up behind you,

we all have different tugs Different gearboxes ,but the one thing I found out when my transmission went into safety mode locked in second gear.

it was caused by two things climbing a mountain range straight up! that never seemed to end,with very tight corners the highway to hell.

the auto oil was dirty although the oil was changed as per book 90K.

now the auto oil is changed every 40K.