D40 and Towing heavy vans

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user 49350

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Hi All,
I have a Thai 2011 (2012 build) D40 4x4 auto and I currently tow a 1500kg (fully loaded with water, food etc) caravan. I do experience some interesting heating issues from time to time. Last trip in Qld was up the hill via Cunningham's Gap on Aussie day in 35 DegC ambient temp. My coolant got to 105, transmission got to 125, and the EGT threw a P1278 fault code (front EGT > 750C for 2 secs) half way up the hill and went into limp mode. Soon recovered without further incident. I am currently checking out approaches like modifying driving habit (using lower gears higher revs) as well as a new oil cooler as mine has a lot of squashed fins / ripples on it, and replacing the front EGT sensor just in case its crook. the ute already has a new Rad from the inaugral trip with the van where it got to a dangerously high temp (no damage thankfully). The new Rad saw temps drop to max 100 C on the same uphill trip. Full coolant flush and using Nulon Heavy Duty 8 Yr / 1,200,000 km coolant now. Also replaced the tranny fluid with new stuff.
Anyhows, I am looking at getting a bigger van, probably another ton so 2500 kg but have reservations as to how the Nav will be up to the task.
I know Old Tony has the same setup and does not seem to have issues. So the question for Old Tony and others is what can I expect when I get the new 2500 kg van?
What precautions should I be taking?
Are there any further mods I should make (extra tranny oil cooling, different coolant fluid etc)?
And yes, I am aware that the high transmission temps are due to the fact the D40 is a bit pathetic with is Torque Convertor lockup only being 5th gear O/D on etc. Still hopefull a new cooler will will help.
Cheers
 
Since I'm mentioned LOL ...

My van is 2550kg fully loaded (I don't think we actually get that far, we might get to about 2400kg tops). I've done - and do - a number of things to keep the engine going nicely.

1) Clear air in front of the radiator. Driving lights and a light bar were just too much, and since the light bar produced more useful light for the power consumed, I ditched the halogen driving lights.

2) Transmission cooler in front of everything. Sure it causes the gearbox to warm up more slowly on cold days, but that doesn't take long and it's better for the gearbox under heavy loads.

3) Use the gears. I'm not afraid to do 15km/h up a hill in first. It's far better than not making it up the hill with coolant spraying everywhere from the crack in the head.

4) If you need extra cooling capacity, use your windows. Wind 'em down. Turn the cabin air to the windscreen, max fan and max heat, aircon OFF.

A good radiator is essential. Mine is fairly new, but I'm considering a more efficient radiator. I've done no research in this regard as yet.

How are you measuring transmission temps? Do you know the PIDs for this data?
 
Thanks for taking the time to reply Old Tony.
Regarding your point 2 - Transmission cooler in front of everything, what do you mean exactly because stock it is in front. Do you mean reposition it up further into the grill?
I might also research a newer more efficient water coolant rad - lets see who beats who in the research.
Finally, Tranny temps - well I hacked the OBDII protocol by sniffing my scanner comms (a Vident I400AU) and then threw together an Arduino with a 5" display on it. No easy task but I got there. The reported temps are a bit ordinary, they go up in 1 degree steps until about 80 then start going up in 5 degree steps. So if I had that time again, I would have just used some thermistor based probes in the oil lines using tee connectors or something.
These are the PIDs
// ATF Temp 1 22 11 0B A-40 °C
// ATF Temp 2 22 11 0C A-40 °C
But you have to place the OBDII K-Line into diagnostic mode using a very specific initialisation sequence. Something Torque and similar apps do not provide the capabilty to do unfortunately (tried that approach till I had 10 headaches).
Cheers
 
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Oh and one more question, with the Rad bottom tank transmission cooler, I am thinking of bypassing that. Not so much that I am worried about the accounts of it failing and flooding the tranny with coolant, more that when I am going uphill under load I know the bottom tank temp climbs to almost 70C (I know because I have an after market temp sensor in the return hose) and I think rather than cooling the tranny oil, its doing a great job of heating it!
Thoughts?
 
Thanks for the info about the transmission temps. I guess I won't sweat those too much then!

Regarding your point 2 - Transmission cooler in front of everything, what do you mean exactly because stock it is in front. Do you mean reposition it up further into the grill?

My car has 3 transmission coolers.

1) Built into the radiator (not connected). This is the factory default.
2) A small cooler mounted low on the aircon condensor to one side (no actual idea where this came from)
3) A large oil cooler that goes across the bottom of the aircon condensor, added at my request.

The radiator was bypassed to prevent damage to the gearbox in case anything broke.
 
Aussie, I have the Spanish STX550 3LTR Diesel so different, but had all the same symptoms, mine I eventually found to be a blown fuse in the IPDM, controlling the fan, I think yours has bi-metallic control. I threw a lot of parts at it before I discovered the fault. Installed an after market trans cooler, bypassed the radiator cooler, still have factory air cooler installed and my trans temp rarely goes over 60-65c. I use sports mode auto when towing, but like Tony says, keep the revs up and load down. I am towing a 2 tonne pop top. According to the workshop manual, normal operating temperature is 85c-105c with max thermostat opening at 105c for the V9x motor. My son has the 2.5 manual and tows 2.5 tonnes, and although only indicating 1/2 on temp gauge was getting close to 105c on my diagnostic machine. It still is disconcerting though, but I now just monitor my standard temp gauge and if air conditioning is still blowing cold air, which is a first indication of rising water temperatures, I don't worry. Speaking of air con, I think the 2.5 has an electric fan in front of the condensor that should cycle everytime the compressor kicks in, is that working? Sorry couldn't be of any help and good luck. Can post some pics of after market cooler if you want.
 
Hi All,
I have a Thai 2011 (2012 build) D40 4x4 auto and I currently tow a 1500kg (fully loaded with water, food etc) caravan. I do experience some interesting heating issues from time to time. Last trip in Qld was up the hill via Cunningham's Gap on Aussie day in 35 DegC ambient temp. My coolant got to 105, transmission got to 125, and the EGT threw a P1278 fault code (front EGT > 750C for 2 secs) half way up the hill and went into limp mode. Soon recovered without further incident. I am currently checking out approaches like modifying driving habit (using lower gears higher revs) as well as a new oil cooler as mine has a lot of squashed fins / ripples on it, and replacing the front EGT sensor just in case its crook. the ute already has a new Rad from the inaugral trip with the van where it got to a dangerously high temp (no damage thankfully). The new Rad saw temps drop to max 100 C on the same uphill trip. Full coolant flush and using Nulon Heavy Duty 8 Yr / 1,200,000 km coolant now. Also replaced the tranny fluid with new stuff.
Anyhows, I am looking at getting a bigger van, probably another ton so 2500 kg but have reservations as to how the Nav will be up to the task.
I know Old Tony has the same setup and does not seem to have issues. So the question for Old Tony and others is what can I expect when I get the new 2500 kg van?
What precautions should I be taking?
Are there any further mods I should make (extra tranny oil cooling, different coolant fluid etc)?
And yes, I am aware that the high transmission temps are due to the fact the D40 is a bit pathetic with is Torque Convertor lockup only being 5th gear O/D on etc. Still hopefull a new cooler will will help.
Cheers
I tow my van which when fully loaded is 2900kg and haven’t experienced any issues, I do a radiator flush when I service the car 2010 D40 2.5 litre dual cab with canopy. Now that I’ve read about your issues I will definitely be getting another oil cooler for the transmission and deleting the radiator one
 
Actually the cooler in the radiator is not a cooler. It is there specifically to get the transmission up to temperature fairly quickly, so actually it is a heater.
Not required I guess in Australia but in countries where zero degrees is common for much of the year it is needed.
 
Actually the cooler in the radiator is not a cooler. It is there specifically to get the transmission up to temperature fairly quickly, so actually it is a heater.
Not required I guess in Australia but in countries where zero degrees is common for much of the year it is needed.

I have noticed on cold mornings (we've actually had -8C mornings a number of winters ago, and I've been up in Northern Tablelands with a -11C start) that the auto box is not very responsive when first starting.

We had a few reports of people off-roading and hitting ground with the nose (eg beach, or coming out of a water crossing) where the hit from underneath causes the trans cooler (heater) to rupture into the coolant, cross-contaminating the transmission and engine coolant - a significant problem. I decided to avoid that, although I'm also fairly careful to not do water crossings that have difficult exits and I don't go on beaches.
 
Aussie, I have the Spanish STX550 3LTR Diesel so different, but had all the same symptoms, mine I eventually found to be a blown fuse in the IPDM, controlling the fan, I think yours has bi-metallic control. I threw a lot of parts at it before I discovered the fault. Installed an after market trans cooler, bypassed the radiator cooler, still have factory air cooler installed and my trans temp rarely goes over 60-65c. I use sports mode auto when towing, but like Tony says, keep the revs up and load down. I am towing a 2 tonne pop top. According to the workshop manual, normal operating temperature is 85c-105c with max thermostat opening at 105c for the V9x motor. My son has the 2.5 manual and tows 2.5 tonnes, and although only indicating 1/2 on temp gauge was getting close to 105c on my diagnostic machine. It still is disconcerting though, but I now just monitor my standard temp gauge and if air conditioning is still blowing cold air, which is a first indication of rising water temperatures, I don't worry. Speaking of air con, I think the 2.5 has an electric fan in front of the condensor that should cycle everytime the compressor kicks in, is that working? Sorry couldn't be of any help and good luck. Can post some pics of after market cooler if you want.
It would be great to see your transmission cooler setup.
Cheers
 
Actually the cooler in the radiator is not a cooler. It is there specifically to get the transmission up to temperature fairly quickly, so actually it is a heater.
Not required I guess in Australia but in countries where zero degrees is common for much of the year it is needed.
In my D40, normally the outlet temp (bottom tank) is less than 50C, and the transmission out temp is 70, so in my case there is a degree of cooling from the coolant rad.
I have also seen the coolant rad bottom temp reach 70 going up hill (outlet is 100 to 105) with the van on and the transmission outlet reaching120-125C. I cant make my mind up if the 70C temp is cooling the tranny temp or if its actually making it worse. Hence why I want to bypass it. I think its worth a go, especially here in Qld where its usually warm.
 
Well I bypassed by Rad for the Transmission cooler and what a mistake.
First drive and the transmission temp ramped up very quickly and on a normal drive without the van it was easily getting to 100C.
I have gone and pout it back the way it was.
 
This makes me want to monitor my transmission temps. My next race event is the Newcastle 500 and there won't be a lot of hillclimbing for that, but I will be back up at the mountain for the Bathurst 6 Hour at Easter - it would be very interesting if I could see my own temps during some of those climbs.

I've been trying to get the OBD PIDs for the ATF temp and keep running into Mode 21 PID 20 with a result of x-85 to provide degrees celcius - but this doesn't seem to work.

The hunt continues!
 
Although I don't tow a caravan, I have been monitoring & troubleshooting my own coolant temp issues ('08 D40 VSK M/T)
I have another thread that I'm planning to update at the end of Summer.

My biggest question remains re engine coolant temps (uphill under load): What is normal?

I'd thought I'd contribute to the "research" options.
This is the radiator I've been keeping up my sleeve if I think it's time to upgrade. Sure, it's expensive. But it's from a decent manufacturer and will likely have no fitment issues etc.

https://www.4x4modsaustralia.com.au/k-sport-performance-radiator-navara-d40-05-2.5l-td
 
So you are the cursed James from the wine group - stop calling me!
:)
Anyways, I can tell you what my norm going up hill with a 1500kg van is and that's around 100-105 depending on the gears you use - and thats usually after a few (3ish) minutes going steeply upward (if you are familiar with the South East Qld - Cunningham's Gap)
When I had a badly blocked radiator I was seeing 120+ which made the trip very stressful. I replaced the Radiator (after thinking the thermostat was gone, pump had issues and the viscus fan was out of wack - all wrong).
Turned out the radiator specialist was right - a 10 year old anything that has temp issues - usually a partially blocked Rad.
Cheers

PS That add you have is for Spain Built, I wonder how different they are from Thai builts, probably mountings I bet.
 
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Hi Tony,
If you are desperate to see Transmission temps then a $100 OBDII dongle like the Autel MaxiAP200 will do it - but you can only see Transmission or Engine (or others like Intelligent power, ABS, Console Meter etc).
Another option I have used is NDSII 2.56 (NDS II – Windows PC - Nisscan) with an Ebay VAG KKL cable.
I have both and I think the NDSII is quite good but still can only talk to one ECU, TCM at a time.

If you have mates that can program Arduino's then that opens the possibility of having dual monitoring of Engine and Transmission if you break into the K-Line wiring and separate the two (that's what I did).
The Diagnostic for OBDII is not a secret, but is complicated - to give you an idea it goes like this (and no I am not trying to prove how clever I am, just happy to share what I learnt):

Intitalisation (this info learnt from someone else's good work - and is also stated in the OBD-II ISO 14230-2 Protocol Specification which is available on a Google search)

Fastinit:
_________ _____ ____ ____
\_____/ \/\/\/\/ \/\/\/\/
300ms 25ms 25ms packet response

1) Wait for 300ms with K line high.
2) Pull K line low for 25 +/- 1 ms
3) Let K line rise high and wait 25ms
4) init serial connection to 10400 baud, 8N1, 1=0Volt 0=12Volt, least significant bit first
5) send package 81 18 FC 81 16 18=dest (TCM=18, ECU=12), f1=our tester id, 81=start comms the 16 is a checksum - add all the numbers before it
6) wait for response 83 FC 18 C1 5D 8F 44 Note the tester ID and TCM/ECU id are swapped cause its the reply back


Reading the data for a Navara around 2012 at least
Generally you have two choices:
Mode 21 Read Data By Local Id
Mode 22 Read Data By Common Id

From what I worked out, Mode 21 is for requesting data one parameter at a time, Mode 22 allows you to structure a multi parameter request then send a "give me all that" type request as often as you need (but no longer than 3 or 5 secs interval else the diag mode ceases). I use Mode 22

Then what you do is setup the request structure like this:
14 AC 81 02 11 03 02 11 04 02 11 06 02 11 08 02 11 0B 02 11 0C DF
The Mode 22 PIDs are specified following the 14 AC 81 (14 is count of numbers between first and last number - in HEX format, AC is the request type and 81 is the first request structure - there are four of those, I only used one - 81, and DF on the end is the checksum - Modulo 256 arithmetic)
So the 02 11 03 translates to 02 = 2 bytes follow, 11 03 is PID Mode 22 11 03 and that is for Output revolutions
and Transmission Temps are the 11 OB and 11 OC

You should get a response like 02 EC 81 6F indicating the car understood what you asked for (EC 81 is the important bit - 2 is the count of data and 6F is the checksum)

Once you have done that, each time you want the data you then send 04 21 81 04 01 AB (more often than at lease once every 3 secs - I do 3 times a second)
Which you will get a response like 07 61 81 02 9B 58 70 68 C0 - after the 07 61 82 is the data (transmission temps are the 70 86 near the right, C0 is the checksum). To get the actual tranny temps you convert the HEX number to Decimal and subtract 40 (e.g. 70 hex = 112 dec, -40 = 72 DegC).

The PIDs are on the web from others, these are the ones I used (in my 2012 D40 Thai Navara):

Engine
Coolant 22 11 01 A-40 °C
Barometer 22 11 06 A*0.53333 mBar
Fuel Temp 22 11 08 A-40 °C
Intake Man Press 22 11 31 A*2 kPa
DPF DP 22 11 41 A/2 kPa
Engine Bay Temp 22 11 42 A-40 °C
Air/Fuel 22 11 54 A*20 Milli Volts
Eng RPM 22 12 01 (A*256+B)*0.0977 RPM
Air Flow 22 12 05 (A*256+B)*0.005 Volts
Intake Volume 22 12 07 (A*256+B)/16 mg/stroke
Exhaust Temp Front 22 12 16 (A*256+B)-40 °C
Exhaust Temp Rear 22 12 17 (A*256+B)-40 °C
AC Pressure Sensor 22 12 1D (A*256+B)*0.005 kPa
Speed Sensor 22 12 1E (A*256+B)*1843/32768 km/h
Set Speed 22 12 1F (A*256+B)*1843/32768 km/h
Cruise Enabled 22 13 0E A and $04
Cruise Set 22 13 0E A and $20

Transmission
Output Rev. 22 11 03 A*32 rpm
Turbine Rev. 22 11 04 A*32 rpm
Carrier Gear Rev. 22 11 06 A*32 rpm
Slip 22 11 08 A*2 rpm
ATF Temp 1 22 11 0B A-40 °C
ATF Temp 2 22 11 0C A-40 °C

Note also,
If you request 22 11 PIDs the responses are one number (hence the formulas above refer only to "A"
If you request 22 12 PIDs the responses are two numbers (hence the formulas above refer to "A" and "B"

And to cap it off, the Arduino needs a special interface chip to convert the 12 volt OBDII levels to 5 volt (or 3.3 volt) Arduino levels. Or you can hack the VAG KKL cable I mentioned above (one for ECO and one for TCU).

Finally, I am time poor so unable to help people build this setup. But the info above should get the code savy people going.

Nothing to it eh :sleep:
 
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That was absolutely fantabulous! I was completely unaware that the ECU had a setting for "Cruise Set", I am SO going to add that one to my screen as soon as I'm back in the Nav (can't at the moment, and tomorrow back for more medical stuff - not for me, I'm just a taxi driver for this).

That is brilliant.

I can't say that I want to start working on Arduino units right now, although they have piqued my curiosity in the past so never say never ...
 
Be interested to see how you go with that Old Tony. Note that "A and $20" means the 6th "bit" in the 8 bit number "A" (so 1=ON or 0=OFF - not a decimal number greater than 1).
One thing I have learnt is that some parameters available over the standard OBDII most people access are not directly available in diag mode.
EG for my Nav, Boost Pressure is not directly available. I have to calculate it by subtracting Barometric Pressure from Inlet Manifold Pressure - despite a PID documented for Boost (reading that fails). Boost is available on standard OBDII.
 
Or u could bolt an engine guard onto ur transmission. Or hack the output line to the radiator/cooler with a temp probe. As in an eight dollar generic water temp probe to a temp gauge. Cheap real time read out.
 
Hi Tony,
If you are desperate to see Transmission temps then a $100 OBDII dongle like the Autel MaxiAP200 will do it - but you can only see Transmission or Engine (or others like Intelligent power, ABS, Console Meter etc).
Another option I have used is NDSII 2.56 (NDS II – Windows PC - Nisscan) with an Ebay VAG KKL cable.
I have both and I think the NDSII is quite good but still can only talk to one ECU, TCM at a time.

If you have mates that can program Arduino's then that opens the possibility of having dual monitoring of Engine and Transmission if you break into the K-Line wiring and separate the two (that's what I did).
The Diagnostic for OBDII is not a secret, but is complicated - to give you an idea it goes like this (and no I am not trying to prove how clever I am, just happy to share what I learnt):

Intitalisation (this info learnt from someone else's good work - and is also stated in the OBD-II ISO 14230-2 Protocol Specification which is available on a Google search)

Fastinit:
_________ _____ ____ ____
\_____/ \/\/\/\/ \/\/\/\/
300ms 25ms 25ms packet response

1) Wait for 300ms with K line high.
2) Pull K line low for 25 +/- 1 ms
3) Let K line rise high and wait 25ms
4) init serial connection to 10400 baud, 8N1, 1=0Volt 0=12Volt, least significant bit first
5) send package 81 18 FC 81 16 18=dest (TCM=18, ECU=12), f1=our tester id, 81=start comms the 16 is a checksum - add all the numbers before it
6) wait for response 83 FC 18 C1 5D 8F 44 Note the tester ID and TCM/ECU id are swapped cause its the reply back


Reading the data for a Navara around 2012 at least
Generally you have two choices:
Mode 21 Read Data By Local Id
Mode 22 Read Data By Common Id

From what I worked out, Mode 21 is for requesting data one parameter at a time, Mode 22 allows you to structure a multi parameter request then send a "give me all that" type request as often as you need (but no longer than 3 or 5 secs interval else the diag mode ceases). I use Mode 22

Then what you do is setup the request structure like this:
14 AC 81 02 11 03 02 11 04 02 11 06 02 11 08 02 11 0B 02 11 0C DF
The Mode 22 PIDs are specified following the 14 AC 81 (14 is count of numbers between first and last number - in HEX format, AC is the request type and 81 is the first request structure - there are four of those, I only used one - 81, and DF on the end is the checksum - Modulo 256 arithmetic)
So the 02 11 03 translates to 02 = 2 bytes follow, 11 03 is PID Mode 22 11 03 and that is for Output revolutions
and Transmission Temps are the 11 OB and 11 OC

You should get a response like 02 EC 81 6F indicating the car understood what you asked for (EC 81 is the important bit - 2 is the count of data and 6F is the checksum)

Once you have done that, each time you want the data you then send 04 21 81 04 01 AB (more often than at lease once every 3 secs - I do 3 times a second)
Which you will get a response like 07 61 81 02 9B 58 70 68 C0 - after the 07 61 82 is the data (transmission temps are the 70 86 near the right, C0 is the checksum). To get the actual tranny temps you convert the HEX number to Decimal and subtract 40 (e.g. 70 hex = 112 dec, -40 = 72 DegC).

The PIDs are on the web from others, these are the ones I used (in my 2012 D40 Thai Navara):

Engine
Coolant 22 11 01 A-40 °C
Barometer 22 11 06 A*0.53333 mBar
Fuel Temp 22 11 08 A-40 °C
Intake Man Press 22 11 31 A*2 kPa
DPF DP 22 11 41 A/2 kPa
Engine Bay Temp 22 11 42 A-40 °C
Air/Fuel 22 11 54 A*20 Milli Volts
Eng RPM 22 12 01 (A*256+B)*0.0977 RPM
Air Flow 22 12 05 (A*256+B)*0.005 Volts
Intake Volume 22 12 07 (A*256+B)/16 mg/stroke
Exhaust Temp Front 22 12 16 (A*256+B)-40 °C
Exhaust Temp Rear 22 12 17 (A*256+B)-40 °C
AC Pressure Sensor 22 12 1D (A*256+B)*0.005 kPa
Speed Sensor 22 12 1E (A*256+B)*1843/32768 km/h
Set Speed 22 12 1F (A*256+B)*1843/32768 km/h
Cruise Enabled 22 13 0E A and $04
Cruise Set 22 13 0E A and $20

Transmission
Output Rev. 22 11 03 A*32 rpm
Turbine Rev. 22 11 04 A*32 rpm
Carrier Gear Rev. 22 11 06 A*32 rpm
Slip 22 11 08 A*2 rpm
ATF Temp 1 22 11 0B A-40 °C
ATF Temp 2 22 11 0C A-40 °C

Note also,
If you request 22 11 PIDs the responses are one number (hence the formulas above refer only to "A"
If you request 22 12 PIDs the responses are two numbers (hence the formulas above refer to "A" and "B"

And to cap it off, the Arduino needs a special interface chip to convert the 12 volt OBDII levels to 5 volt (or 3.3 volt) Arduino levels. Or you can hack the VAG KKL cable I mentioned above (one for ECO and one for TCU).

Finally, I am time poor so unable to help people build this setup. But the info above should get the code savy people going.

Nothing to it eh :sleep:
its a long time since your post, great information. are you able to share the arduino code used and wiring changes rquired please? I have a couple of arduinos gathering dust.
Also where is the best place to find all the pids for v9x engine and D40 auto trans please.
 

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