I pull my 20ft Jayco caravan with a 2018 Isuzu D-MAX, 6 speed automatic. I have been told you should never tow a caravan in overdrive but drive it like its a manual.
What I would like to know is when I drive it as if it were a manual 6th gear shows on the dash.
Is 6th gear classed as an overdrive or is it OK to drive it in that gear when towing, or switch back to 5th gear?
Thank You.
Ken.
yobarr said
03:57 PM Jun 17, 2020
kenglenn111 wrote:
I pull my 20ft Jayco caravan with a 2018 Isuzu D-MAX, 6 speed automatic. I have been told you should never tow a caravan in overdrive but drive it like its a manual.
What I would like to know is when I drive it as if it were a manual 6th gear shows on the dash.
Is 6th gear classed as an overdrive or is it OK to drive it in that gear when towing, or switch back to 5th gear?
Thank You..Ken.
Hi Ken....I will not offer any advice about the wisdom of towing in overdrive,but I am pretty sure that in your vehicle's gearbox ,both 5th and 6th are overdrive.Cheers
kenglenn111 said
04:17 PM Jun 17, 2020
Thanks Yobarr.
dabbler said
04:19 PM Jun 17, 2020
Read your vehicle's manuals or ask your dealer's service staff. They will have information to your vehicle.
Overdrive typically refers to gearbox ratios (hence Yobarr's comment). It doesn't describe how and when the gearbox moves through gear selection and that is the important factor.
Aus-Kiwi said
04:48 PM Jun 17, 2020
Its more to do with sweet spot on your engine and driveline . Top gear engines rpm could be way too low for the speed your doing ?? Check where torque is best ? Always change down on hills or high load, wind etc . If you need too much throttle to maintain your speed ? Chances are the engine needs a little assistance with ratios, multification factor ..
markf said
06:27 PM Jun 17, 2020
I don't know a thing about D-MAX gearboxes apart from them being a torque converter lockup transmission but...
In my Discovery 2 it's important to maintain torque converter lockup to avoid transmission oil overheating and premature wear. I assume that the D-MAX gearbox does much the same thing so drive in a gear that maintains TC lockup.
In my D2 the TC locks up at about 70kph in "3" and at around 80kph in "D" and I've heard of people fitting a TC lockup switch to a D-MAX. Without the switch keep in in "lockup" and when it drops out of "lockup" change down to get it to lockup again.
This may, or may not, muddy the waters even further for you.
travelyounger said
07:36 PM Jun 17, 2020
HiKenglenn
I have a 2017 dmax 6 speed auto towing 3 tonne van. I most of the time tow in manual and usually are in forth gear because I find it is more economical and there is less labouring on the engine and is in the torque curve.Beware towing in manual as the gears will not change down and possible overheating of gearbox oil .I had izuzu in Adelaide update the software and now changes down automatically in manual before overheating the transmission.Give north east Izuzu Adelaide a call as I have found most other franchises don't know or don't care and just say tow in auto hope this helps
cjt55 said
02:08 AM Jun 18, 2020
I have a V6 Nissan Navara Twin Cab Ute with 7 speed auto and tow a 2.7 ton van loaded. I use manual mode and only tow using maximum 5th gear. At 90kph I am sitting around 2000rpm. Never had a problem.
-- Edited by cjt55 on Thursday 18th of June 2020 02:09:24 AM
-- Edited by cjt55 on Thursday 18th of June 2020 02:10:58 AM
Mike Harding said
06:49 AM Jun 18, 2020
I suspect the D-max is similar to my Trailblazer; 5 is about 0.8:1 and 6 about 0.6:1, ie both are overdrive gears and not really suitable for towing the 2.8T of my van.
Around town I tow in auto because it's convenient and the box will rarely, if ever, get into 5 or 6 but outside urban areas I switch to manual and tow in 4 or occasionally 5 if on the flat, never 6.
I also ensure torque converter lock-up - blip the throttle and if the revs jump the converter is open if they don't then it's locked - this minimises transmission fluid heating. I also drive with transmission fluid temperature showing on the display and ensure it doesn't rise above about 95C.
Maximum torque for my 2.8L diesel engine is produced around 1700 to 2100RPM and I try to keep the revs in that band.
A good question.
kenglenn111 said
08:58 AM Jun 18, 2020
Thanks everyone, I think I have the idea now.
Ken.
Izabarack said
03:39 PM Jun 18, 2020
My method in my DMax is to put the thing in D and just drive. I remain aware of what is up ahead and maybe the need to drop it down a cog but mostly I listen for sounds of straining. Long flat straights at a steady speed and the thing holds 6th. Done about 40,000 K, towing, since new and no problems. I never put the boot in hard and let the gearbox make its own decisions.
Iza
Delta18 said
06:54 PM Jun 18, 2020
I have a 2017 6 speed D-Max and tow a 3.3t Silverline.
I always tow in D, there is never any labouring of the engine as the ECU is too smart to allow that, it changes down if necessary before I get a chance to think about it.
I normally tow, conditions permitting, at around 100kmh (gps speed) and on flat roads achieve 12 - 14L/100km. The transmission givers between 5th & 6th mostly but if a hill of any sort is encountered it will shift back to 4th.
Cheers Neil
Radar said
07:55 PM Jun 18, 2020
cjt55 wrote:
I have a V6 Nissan Navara Twin Cab Ute with 7 speed auto and tow a 2.7 ton van loaded. I use manual mode and only tow using maximum 5th gear. At 90kph I am sitting around 2000rpm. Never had a problem.
Hi to another Nissan Navara V6 turbo owner.
Last year while we were away outback NSW & South Australia we experienced a fault code appeared in our awesome Navara with 120000k's on the clock.
After a number of phone calls to different Nissan Dealers without much success and I was getting a bit desperate when a call come in from Broken Hill dealer 400k's away. This service guy who had learnt of my problem though the Nissan grape vine said to me "you have caused the problem". How do you know that I fried back "you young peep squeek".
He goes on to say, you are driving it in "D" towing 3 tonne caravan at 90k's right, you are causing the code when the auto heats up. Unfortunately that is how I was operating the car, it was hardly working but unknownly dropping in and out 6, at worse 7th gear, not good for the auto, just over heats the gearbox and the next thing it goes into limp mode, showing a code. Clear the code and away you go again.
A further 15000k's and not a issue, I now drive in Manual mode towing the caravan or if I get lazy sports mode though towns.
We will in the near future have the automatic service but first I need to give up drinking, eating and rob a bank. Bugger.
Heed the warning when towing, you only manual/sports mode.
kenglenn111 said
12:16 PM Jun 19, 2020
Good afternoon All,
Firstly, thank you for all of your replies about towing.
I spoke to an Isuzu dealer this morning and he told me that the gearbox is design to allow you to tow a caravan in drive. He also said that 5th & 6th gears are both overdrive when using it as a manual.
Ken
Amigo1 said
08:49 AM Jun 20, 2020
kenglenn111 wrote:
Good afternoon All,
Firstly, thank you for all of your replies about towing.
I spoke to an Isuzu dealer this morning and he told me that the gearbox is design to allow you to tow a caravan in drive. He also said that 5th & 6th gears are both overdrive when using it as a manual.
Ken
The dealers comment is backed up in the following You Tube video up by the somewhat controversial and sometimes potty-mouthed Auto expert, John Cadogan, who in his own inimical way gives an explanation of why one should tow caravans in Drive/Auto almost at all times, using the car's transmission and computer control systems for what they are engineered to do and in a way much better than we can. Sorry if it has been posted previously.
https://www.youtube.com/watch?v=swUDFWQ5QhI
Cheers, Phillip
PS: As usual, John is most tongue-in-cheek (some might say derogatory!) about caravanning and the life of we Grey Nomads, but what he says normally makes sense
Jaahn said
11:37 AM Jun 20, 2020
Hi
My comment, sorry I do not have the high profile of John or a dealer mechanic but I will say my piece anyway.
The problem is IMHO not the strength of the mechanicals or even the oil and clutches or torque converter operation, it is in the software. The complicated operation of modern vehicles and the use of computer control has lead to great improvements in comfort, smoothness and improved fuel economy with more power and most people do not complain about all those. That is what gets you into the new cars and tugs. BUT the software in the computer is designed for the average user with some adaptive learning and for a world market as well.
Really the only way that a GN tug differs from the average use is effectively a doubling++ of the tug weight and vastly increased drag. What could go wrong there And the only way the driver can influence the computer program is to use the manual/sports mode. That modifies by using different software programs in the computer. Sounds good to me ! It might seem that another 'button' or selection would go a long way to solving the problems some encounter, but until that time use the selector you were given to best advantage are my thoughts.
Jaahn
Kebbin said
12:03 PM Jun 20, 2020
Phillip you said you spoke to the dealer about towing, just to clarify was he/she also a mechanic or workshop manager?
I had a squiz at your manual and the mob that makes ém say Sports Mode especially around hills? Before you have problems I suggest you read your manual, it wasn't under towing I think from memory it was in the Gearbox section not sure.
2trout said
12:26 PM Jun 20, 2020
Keebbin is right. Use "sports" mode or you run the risk of wrecking your gearbox. And the fuel economy is the same.
Amigo1 said
02:42 PM Jun 20, 2020
Kebbin wrote:
Phillip you said you spoke to the dealer about towing, just to clarify was he/she also a mechanic or workshop manager? (OP's comment not mine)
I had a squiz at your manual and the mob that makes ém say Sports Mode especially around hills? Before you have problems I suggest you read your manual, it wasn't under towing I think from memory it was in the Gearbox section not sure.
Hi Kebbin,
Thanks for the feedback. I value it. I was quoting the OP in my post when I said that the dealer's comment about his Isuzu was backed up by one "expert". Hereunder are some facts from Ford on the subject rather than from their dealers or mechanics.
I tow with a MY 2015 Everest which says on p131 of its owners manual that: "Note: In sport (i.e. manual) mode the transmission operates as normal but gears are selected more quickly and at higher engine speeds. Note: In sport mode S will be shown in the instrument cluster display. Note:When towing heavy loads or in hilly terrain, it is recommended that sport mode is selected. This will result in cooler transmission temperatures and additional engine braking."
The latest MY2019 Everest with a bi-turbo engine has a new transmission feature called "PRS or "Progressive Range Select". It is described as: With the bi-turbo engine, Everests towing capacity increases to 3100 kilograms. The top three gears are overdrive ratios (greater than 1:1) which is not always ideal when hauling close to maximum load, but Ford says there is no need to avoid any gears when towing; the 10-speed will decide the right gear for the situation. However, its possible to override the transmission through PRS which allows progressive lock-out of the high gears or for as many gears as the driver wants. In PRS mode, the transmission continues to shift automatically but only up to the maximum gear selected.
My underlined parts of the above excerpts highlight Ford's differing suggestions for use of Drive and Manual modes for the two Everest models. I am guessing that that new feature of being able to lockout gears progressively, starting from the highest, has been incorporated for people to be better able to manage keeping out of overdrive gears when towing loads? My intuition tells me that this feature might have been developed to address a common transmission overheating problem often discussed on the Everest Owners Facebook Forum but not likely to be admitted by Ford as an Everest design issue.
In conclusion,what seem to a common thread in most discussions on this subject is that when towing loads one should avoid the use of overdrive gears, regardless of whether they are selected by the transmission system's computer or by the driver in manual mode. Exactly what gfears are classified as "overdrive" will vary by vehicle type.
BTW I have never had any problem with my Everest towing in both Manual and Drive modes after 40K+ kilometers of towing.
Cheers, Phillip
Radar said
03:23 PM Jun 20, 2020
Amigo1 wrote:
Kebbin wrote:
Phillip you said you spoke to the dealer about towing, just to clarify was he/she also a mechanic or workshop manager? (OP's comment not mine)
I had a squiz at your manual and the mob that makes ém say Sports Mode especially around hills? Before you have problems I suggest you read your manual, it wasn't under towing I think from memory it was in the Gearbox section not sure.
Hi Kebbin,
In conclusion,what seem to a common thread in most discussions on this subject is that when towing loads one should avoid the use of overdrive gears, regardless of whether they are selected by the transmission system's computer or by the driver in manual mode. Exactly what gfears are classified as "overdrive" will vary by vehicle type.
BTW I have never had any problem with my Everest towing in both Manual and Drive modes after 40K+ kilometers of towing.
Cheers, Phillip
We are up around 70 000kilometres of towing, 115 000 kilometres combined use when ours problem started. From what I am reading here is people are not giving any idea of there kilometres, it would be very interesting to read of people with higher end kilometres on there cars and how their auto matics are still performing.
Like I was talking with a guy with a similar car to mine, brought around the same time and he telling what great car it is, has not spent any money on it, tows about 2.5 tonnes, took me for ever to get it out of him, 6 years old, 4000ks of towing and sold the car with 40000ks on it Hello, I did not spend any money on mine until it had 50 000ks on it, every 10 thousand ks since we have found there is something as with all cars whether it be tyres, shock absorbers, front disc brake rotors, battery, tyres again and then the inter cooler split. It still a good car.
Delta18 said
04:35 PM Jun 20, 2020
Kebbin wrote:
Phillip you said you spoke to the dealer about towing, just to clarify was he/she also a mechanic or workshop manager?
I had a squiz at your manual and the mob that makes ém say Sports Mode especially around hills? Before you have problems I suggest you read your manual, it wasn't under towing I think from memory it was in the Gearbox section not sure.
I dont know what manual you looked in but Isuzu D-Max do not have a Sports Mode!
I pull my 20ft Jayco caravan with a 2018 Isuzu D-MAX, 6 speed automatic. I have been told you should never tow a caravan in overdrive but drive it like its a manual.
What I would like to know is when I drive it as if it were a manual 6th gear shows on the dash.
Is 6th gear classed as an overdrive or is it OK to drive it in that gear when towing, or switch back to 5th gear?
Thank You.
Ken.
Hi Ken....I will not offer any advice about the wisdom of towing in overdrive,but I am pretty sure that in your vehicle's gearbox ,both 5th and 6th are overdrive.Cheers
I don't know a thing about D-MAX gearboxes apart from them being a torque converter lockup transmission but...
In my Discovery 2 it's important to maintain torque converter lockup to avoid transmission oil overheating and premature wear. I assume that the D-MAX gearbox does much the same thing so drive in a gear that maintains TC lockup.
In my D2 the TC locks up at about 70kph in "3" and at around 80kph in "D" and I've heard of people fitting a TC lockup switch to a D-MAX. Without the switch keep in in "lockup" and when it drops out of "lockup" change down to get it to lockup again.
This may, or may not, muddy the waters even further for you.
HiKenglenn
I have a 2017 dmax 6 speed auto towing 3 tonne van. I most of the time tow in manual and usually are in forth gear because I find it is more economical and there is less labouring on the engine and is in the torque curve.Beware towing in manual as the gears will not change down and possible overheating of gearbox oil .I had izuzu in Adelaide update the software and now changes down automatically in manual before overheating the transmission.Give north east Izuzu Adelaide a call as I have found most other franchises don't know or don't care and just say tow in auto hope this helps
I have a V6 Nissan Navara Twin Cab Ute with 7 speed auto and tow a 2.7 ton van loaded. I use manual mode and only tow using maximum 5th gear. At 90kph I am sitting around 2000rpm. Never had a problem.
-- Edited by cjt55 on Thursday 18th of June 2020 02:09:24 AM
-- Edited by cjt55 on Thursday 18th of June 2020 02:10:58 AM
I suspect the D-max is similar to my Trailblazer; 5 is about 0.8:1 and 6 about 0.6:1, ie both are overdrive gears and not really suitable for towing the 2.8T of my van.
Around town I tow in auto because it's convenient and the box will rarely, if ever, get into 5 or 6 but outside urban areas I switch to manual and tow in 4 or occasionally 5 if on the flat, never 6.
I also ensure torque converter lock-up - blip the throttle and if the revs jump the converter is open if they don't then it's locked - this minimises transmission fluid heating. I also drive with transmission fluid temperature showing on the display and ensure it doesn't rise above about 95C.
Maximum torque for my 2.8L diesel engine is produced around 1700 to 2100RPM and I try to keep the revs in that band.
A good question.
Ken.
Iza
I have a 2017 6 speed D-Max and tow a 3.3t Silverline.
I always tow in D, there is never any labouring of the engine as the ECU is too smart to allow that, it changes down if necessary before I get a chance to think about it.
I normally tow, conditions permitting, at around 100kmh (gps speed) and on flat roads achieve 12 - 14L/100km. The transmission givers between 5th & 6th mostly but if a hill of any sort is encountered it will shift back to 4th.
Cheers Neil
Hi to another Nissan Navara V6 turbo owner.
Last year while we were away outback NSW & South Australia we experienced a fault code appeared in our awesome Navara with 120000k's on the clock.
After a number of phone calls to different Nissan Dealers without much success and I was getting a bit desperate when a call come in from Broken Hill dealer 400k's away. This service guy who had learnt of my problem though the Nissan grape vine said to me "you have caused the problem". How do you know that I fried back "you young peep squeek".
He goes on to say, you are driving it in "D" towing 3 tonne caravan at 90k's right, you are causing the code when the auto heats up. Unfortunately that is how I was operating the car, it was hardly working but unknownly dropping in and out 6, at worse 7th gear, not good for the auto, just over heats the gearbox and the next thing it goes into limp mode, showing a code. Clear the code and away you go again.
A further 15000k's and not a issue, I now drive in Manual mode towing the caravan or if I get lazy sports mode though towns.
We will in the near future have the automatic service but first I need to give up drinking, eating and rob a bank. Bugger.
Heed the warning when towing, you only manual/sports mode.
Firstly, thank you for all of your replies about towing.
I spoke to an Isuzu dealer this morning and he told me that the gearbox is design to allow you to tow a caravan in drive. He also said that 5th & 6th gears are both overdrive when using it as a manual.
Ken
The dealers comment is backed up in the following You Tube video up by the somewhat controversial and sometimes potty-mouthed Auto expert, John Cadogan, who in his own inimical way gives an explanation of why one should tow caravans in Drive/Auto almost at all times, using the car's transmission and computer control systems for what they are engineered to do and in a way much better than we can. Sorry if it has been posted previously.
https://www.youtube.com/watch?v=swUDFWQ5QhI
Cheers, Phillip
PS: As usual, John is most tongue-in-cheek (some might say derogatory!) about caravanning and the life of we Grey Nomads, but what he says normally makes sense
Hi
My comment, sorry I do not have the high profile of John or a dealer mechanic but I will say my piece anyway.
The problem is IMHO not the strength of the mechanicals or even the oil and clutches or torque converter operation, it is in the software. The complicated operation of modern vehicles and the use of computer control has lead to great improvements in comfort, smoothness and improved fuel economy with more power and most people do not complain about all those. That is what gets you into the new cars and tugs. BUT the software in the computer is designed for the average user with some adaptive learning and for a world market as well.
Really the only way that a GN tug differs from the average use is effectively a doubling++ of the tug weight and vastly increased drag. What could go wrong there
And the only way the driver can influence the computer program is to use the manual/sports mode. That modifies by using different software programs in the computer. Sounds good to me ! It might seem that another 'button' or selection would go a long way to solving the problems some encounter, but until that time use the selector you were given to best advantage are my thoughts. 
Jaahn
I had a squiz at your manual and the mob that makes ém say Sports Mode especially around hills? Before you have problems I suggest you read your manual, it wasn't under towing I think from memory it was in the Gearbox section not sure.
Hi Kebbin,
Thanks for the feedback. I value it. I was quoting the OP in my post when I said that the dealer's comment about his Isuzu was backed up by one "expert". Hereunder are some facts from Ford on the subject rather than from their dealers or mechanics.
I tow with a MY 2015 Everest which says on p131 of its owners manual that: "Note: In sport (i.e. manual) mode the transmission operates as normal but gears are selected more quickly and at higher engine speeds. Note: In sport mode S will be shown in the instrument cluster display. Note:When towing heavy loads or in hilly terrain, it is recommended that sport mode is selected. This will result in cooler transmission temperatures and additional engine braking."
The latest MY2019 Everest with a bi-turbo engine has a new transmission feature called "PRS or "Progressive Range Select". It is described as: With the bi-turbo engine, Everests towing capacity increases to 3100 kilograms. The top three gears are overdrive ratios (greater than 1:1) which is not always ideal when hauling close to maximum load, but Ford says there is no need to avoid any gears when towing; the 10-speed will decide the right gear for the situation. However, its possible to override the transmission through PRS which allows progressive lock-out of the high gears or for as many gears as the driver wants. In PRS mode, the transmission continues to shift automatically but only up to the maximum gear selected.
My underlined parts of the above excerpts highlight Ford's differing suggestions for use of Drive and Manual modes for the two Everest models. I am guessing that that new feature of being able to lockout gears progressively, starting from the highest, has been incorporated for people to be better able to manage keeping out of overdrive gears when towing loads? My intuition tells me that this feature might have been developed to address a common transmission overheating problem often discussed on the Everest Owners Facebook Forum but not likely to be admitted by Ford as an Everest design issue.
In conclusion,what seem to a common thread in most discussions on this subject is that when towing loads one should avoid the use of overdrive gears, regardless of whether they are selected by the transmission system's computer or by the driver in manual mode. Exactly what gfears are classified as "overdrive" will vary by vehicle type.
BTW I have never had any problem with my Everest towing in both Manual and Drive modes after 40K+ kilometers of towing.
Cheers, Phillip
We are up around 70 000kilometres of towing, 115 000 kilometres combined use when ours problem started. From what I am reading here is people are not giving any idea of there kilometres, it would be very interesting to read of people with higher end kilometres on there cars and how their auto matics are still performing.
Like I was talking with a guy with a similar car to mine, brought around the same time and he telling what great car it is, has not spent any money on it, tows about 2.5 tonnes, took me for ever to get it out of him, 6 years old, 4000ks of towing and sold the car with 40000ks on it Hello, I did not spend any money on mine until it had 50 000ks on it, every 10 thousand ks since we have found there is something as with all cars whether it be tyres, shock absorbers, front disc brake rotors, battery, tyres again and then the inter cooler split. It still a good car.
I dont know what manual you looked in but Isuzu D-Max do not have a Sports Mode!