Towing in overdrive.

[Ken]

Hi all, We have a 2008 Navara 2.5 diesel with a 6 speed box. We sometimes tow our 2.7t caravan with it , and although the ute will tow in overdrive lots of time, I am wondering if I should stay in 5th. I don't make the motor work hard and change to 5th as soon as the motor starts to work . I sit around 90kmh which is about 83 on the gps. What's the general feeling on this?
This ute has done around 33000kms and I just love it. Took a while to get used to driving around town under the limit, but so far going really well. Had the towbar checked the other day on recall but got the green light.
I enjoy the forum site and have learned a lot from you people.
Cheers,
Ken

 

[doc]

I've got the same age and drivetrain configuration as you, and we tow a van which is ~2.5T. Mate, the gearboxes in these things are made out of old railway ties and tank armour. They are pretty solid, so don't worry about that 6th gear giving up the ghost.

What I've found is that the ute simply won't hold 6th gear on anything other than absolute flat road or downhill. Bring the speed up to 100 and it'll hold it, but I prefer to travel at 90-95. At that speed, 5th is the gear that just works best for me.

What Ive also found is that the lower gear produces better economy when towing, as I can be "lighter" on the loud pedal.

I've got a chip fitted too.

 

[KraftyPg]

That's what it's there for so use it.

If manufacturers didn't expect you use all the gears under all circumstances there would be warning stickers telling you so.

Drive the car, listen to the car and take the actions you know you need too. I'd consider increasing the speed to mid 90's just to give yourself a bit more go before you need to change down but I certainly wouldn't ignore one cog just because there is a box behind you.

You should be able to increase the speed to low to mid 90's without having much effect on the vehicle, the caravan or even economy, in fact you might notice an improvement on economy because you may not have to change gears as often and you might be able to maintain a rev range easier.

 

[Mairs]

You'll use less fuel in 6th gear, but just listen to your engine & watch the revs & you'll know what to do. When we're towing we generally change into 6th around 90kms. If you're actually travelling at around 83km I wouldn't want to be behind you!!!...LOL

 

[Busiboy]

I'd avoid towing in overdrive with a heavy load, I've got a friend that played around with the same and said that not using overdrive while towing improved economy.

 

[bods]

That's what it's there for so use it.

If manufacturers didn't expect you use all the gears under all circumstances there would be warning stickers telling you so.

Drive the car, listen to the car and take the actions you know you need too. I'd consider increasing the speed to mid 90's just to give yourself a bit more go before you need to change down but I certainly wouldn't ignore one cog just because there is a box behind you.

You should be able to increase the speed to low to mid 90's without having much effect on the vehicle, the caravan or even economy, in fact you might notice an improvement on economy because you may not have to change gears as often and you might be able to maintain a rev range easier.

hmmm, you better tell that to the patrol drivers that were blowing up 5th gear, sometimes even without towing anything...

it is not recommended to tow in any overdrive gear, unless on flat road or downhill. i would have thought there'd be something in the owners manual about that..

 

[KraftyPg]

I'll tell what I think to anyone I don't give a shit what they drive.

If they put all those cogs in the box they are expected to be used. Nissan or Toyota or any other manufacturer don't put stipulations on what gear does what, if the owner of the vehicle is too stupid to work out that their driving ability doesn't allow them to drive in a particular gear at all times then they deserve to have fcuked gearboxes.

It's got 6 cogs use 6 cogs but just like when you aren't towing listen to the car and let it tell you when to change gears, if you can't do that get a bike.

 

[Old.Tony]

Welcome to the forum, Ken.

If you're not straining the thing, there's nothing wrong with using overdrive. In the auto I leave mine in overdrive because below 120km/h it just unlocks the torque converter and kicks down a gear as needed to prevent strain - above 120km/h you put your foot down and it just belts along harder.

For my money it's not so much what SPEED you drive at - it's what RPM you drive at. The 2.5L CRD engine develops its maximum torque around 2,000rpm. That's the point where you want to be cruising. Any lower and you're not getting enough power out of the engine for the fuel going in and any higher you're using more fuel than you need to for the power you're developing. 2,000rpm happens to be exactly at the point where the sharply-rising torque vs rpm curve starts to level out.

 

[big zetor]

5th gear is the drive gear in the 6 speed, I've seen what the exhaust temps get up to when labouring this engine towing 3 tonn of wood (700+ post turbo) so i'd rather rev it couple of extra hundred and let it do it easy, but at the end of the day you just change gear if its doing it hard! simple.

 

[Ken]

Towing in o/d

Thank you all for your replies.You have confirmed what I was thinking. I was proberbly conservative when I said 90km. 95 gives me just under 90 true speed, and there is where the motor is happy. I know some o/ds are a bit soft, but I am sure these are good.
After 45 years and more than 1m kays in trucks, I am more than happy to pull over to let people pass. I spent too much time sitting behind some dh in a van who thought the road was all his. When we are vanning, I hold that we are cruising, and trucks and others are trying to earn a quid , so let them pass and do just that.
Thank you gentlemen for your help.
Regards, Ken