D40 gets hot when towing - SOLVED

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If its like all the other D40s ive seen that are over fueled then its probably just getting to hot with the bigger load on it, thats why i was saying to keep it in a higher gear. The more you labour the engine and not rev it you'll be pumping unburnt fuel through it and heat it up. I got this advice from a highly skilled Komatsu mechanic who has had numerous cars over half a million k's on his cars and he revs them when towing.

The revs are there for a reason
 
i have an egt gauge on mine and if you labour it the motor will easley go over 700 degrees towing my 2.8 tonn trailer! throw it back in 4th and temps drop by 70 to 100 degress and it' s reving more. i try to keep it under 600 degress most of the time but it dosen't effect my coolent gauge it stays the same.
 
i have an egt gauge on mine and if you labour it the motor will easley go over 700 degrees towing my 2.8 tonn trailer! throw it back in 4th and temps drop by 70 to 100 degress and it' s reving more. i try to keep it under 600 degress most of the time but it dosen't effect my coolent gauge it stays the same.

Do you find your fuel economy heads north while the EGT heads south?

I have tried towing in 4th & the economy is shocking.
 
yeah the higher the egts the more fuel it burns! I'm running 285's so my gearing is a bit taller 70 to 80 in 3rd' 80 to 90 in 4th' 90 to 110 5th' and 110 to130 6th
 
Hey guys sorry for late reply
Tried using a lower gear has helped a bit, did notice the fan doesn't seem to want to engage as hard as it should rang up Nissan to order one and the guy said to get it checked out to make sure sensors are telling it to engage( I thought it just kicked when it got hot but he said the computer done that I told him it was the big fan on the water pump and he said yep that one is run by sensors). Was nice of him saved me a grand was wondering if anyone knows about this as I can't find any wires to it I thought it tightened up as it had hotter air hitting the clutch
 
a little hint for a d40 overheating issue, nissan had issues with the coolant resovour bottle not moulded properly and over time the radiator cap on the bottle wouldnt seal properly, thus causing it to overheat. be something to check
 
There is two options for fans.
A mechanical option if you don't have A/C and a motor driven option if you do have A/C which is controlled by ECU.( Does yours bring up a fault code P0217 or haven't you let it get that hot?).

Here is a test you can do to check the operation of the fan (plus other functions).

Auto Active Test
DESCRIPTION
In auto active test mode, operation inspection can be performed when IPDM E/R sends a drive signal to
the following systems:
– Rear window defogger
– Front wiper
– Tail lamps, front fog lamps, parking lamps and license plate lamps
– Headlamps (HI, LO)
– A/C compressor (magnetic clutch)
– Cooling fan
– Oil pressure warning lamp
OPERATION PROCEDURE
1. Close hood and front door passenger side, and then lift wiper arms away from windshield (to prevent
glass damage by wiper operation).
NOTE:
When auto active test is performed with hood opened, sprinkle water on windshield beforehand.
2. Turn ignition switch OFF.
3. Turn ignition switch ON and, within 20 seconds, press driver's door switch 10 times (close other doors).
Then turn ignition switch OFF.
4. Turn ignition switch ON within 10 seconds after ignition switch OFF.
5. When auto active test mode is actuated, oil pressure warning lamp starts blinking.
6. After a series of operations is repeated three times, auto active test is completed.
NOTE:
When auto active test mode has to be cancelled halfway, turn ignition switch OFF.

During this test the cooling fan should run for 5 seconds on Low and then 5 seconds on High on each cycle of which there is 3.

Hope this makes sense and can help.
 
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I haven't let it get that hot, does this operate the thermo looking fan on rhs of radiator( looking from drivers seat)? Or are you referring to the fan on the water pump?
I will try it to see if it's working anyway
Thanks
 
Just done the auto test everything worked just a click in the fan then it kicked in on low then hi. No codes apearred on the dash so I guess that tells me it's all good with the electric fan
 
Mate I had a 2003 patrol it did exactly the same think, put new fan, watet pump on still did it turned out the radiator was blocked, apparently a common thing for the patrol over time the tubes in the core are pretty thin get sucked in then cause a blockage, the radiator place showed me mine and it was 2/3 blocked. It would have cost me a fortune but it was done under warranty, talk to a radiator place it cost about $360 a couple yrs ago to have it pulled out, pull apart and clean,

Cheers Lyle
 
Yeah I am starting to leaning towards the radiator, it has just been near impossible to get any where to get it done as I'm interstate driver only back on weekends. But will have some time to get it in shortly, hopefully that will sort it then get some other stuff underway with it.

Thanks for the suggestions every one
 
Sorry to take so long to get back, radiator had calcified a bit thanks to our town water. New radiator and going great
 
great outcome, at least it wasnt the head or gasket and you got it sorted before it boiled.
 

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