2019 CX-5 Diesel Aftermarket Transmission Cooler

@GotRice23 I appreciate all the time you've taken to post your trans cooling adventure. Thanks!

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What is your setup for your obdii reader/display?
 
@Kedis82ZE8 - The shop says they'd be willing, but they didn't make any measurements while they were doing mine. Therefore, they wouldn't be able to duplicate the adapter without another CX-5 in their shop. But they said they'd definitely reproduce the adapter if there is interest.

I'm fine with cooling on mine but I think there could be a market for them if they put something out there.
 
Wish I had joined this forum sooner to exchange conversations. I live in Thailand and I own a 2014 cx5 2.2D awd and just got myself a small caravan as well and wanted to keep the temperatures in check, so I used forscan to start logging the temperatures. I was cruising at 80km/h and outside temp while raining was 25c. Below are the numbers:
ECT = 105c
EOT = 114c
TFT = 111c

I happened to monitor the temp before picking up the Caravan on the same day and I was cruising at 120km/h

ECT = 89c
EOT = 94c
TFT = 94c

I was on flat surface at both times.
The caravan weights about 1,150 kg.

Now.. I didnt even want to think how hot they would be if I had to go on steep hills plus when the DPF starts its' regeneration cycle.

I went to a local shop which specializes in customizing/installing transmission and engine oil cooler.

The shop custom built a lot of transmission adapters to replace the existing OEM heat exchange adapter.

I had the car fitted with transmission and engine oil coolers along with their custom adapter plates (engine oil adapter not shown here as I didn't have a chance to snap any photo).

These are the numbers after having the coolers installed.
Outside temp 35c. Speed at 80 km/h
ECT = 89c
EOT = 90c
TFT = 85c

Here is one thing I notice, if I am being more aggressive on my gas pedal doing 100-110km/h, all the temperatures went up roughly 10celcius more and they remain there for a very long time even after reducing speed to 80km/h.
I suspect that, somehow, those air going through the front grill of the car doesn't go through those coolers enough to cool them down. I say this because when I come to a complete stop and let it idle while the fan kicks in at full speed, all the temp went to average numbers within 10 minutes.

So, my next project is to drill enough holes of that fog lamp cover, relocate one of the coolers, fit a dedicated fan that is controlled by thermostat to allow for a command when to activate a fan.

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I also think that diesel runs hotter than petrol (N/A models) variant due to the dpf sitting right after the turbo which may be the reason why the coolers aren't needed for them
 
@Coolpix99 Have you been monitoring EGT, especially during the regen cycle? What are those temperatures looking like for you? I've only just started monitoring them and it looks like I get around 1200 F or 649 C during the regen cycle without the trailer. I'm towing again in the next coming weeks to close out the camping season and will be watching mine closely.
 
@Coolpix99 Have you been monitoring EGT, especially during the regen cycle? What are those temperatures looking like for you? I've only just started monitoring them and it looks like I get around 1200 F or 649 C during the regen cycle without the trailer. I'm towing again in the next coming weeks to close out the camping season and will be watching mine closely.
My regen usually hovers around nearly 600 to 650 celcius without trailer. With trailer it reached 750 celcius max.
However, I decided to remove my dpf and egr just two weeks back and also installed an additional catalytic converter to reduce the diesel smell. One of the reasons was because my dpf was regenerating every 100km with the trailer on and low fuel light came up after 350km with the trailer on.
 
My regen usually hovers around nearly 600 to 650 celcius without trailer. With trailer it reached 750 celcius max.
However, I decided to remove my dpf and egr just two weeks back and also installed an additional catalytic converter to reduce the diesel smell. One of the reasons was because my dpf was regenerating every 100km with the trailer on and low fuel light came up after 350km with the trailer on.
Hmm, hopefully I run into similar results when I do my tow in a couple of weeks. Your emissions are probably now on par with North American standards! I know our emissions control system lowers fuel economy a tiny bit.

Follow up question - what kind of caravan are you towing and what is the weight?
 
Hmm, hopefully I run into similar results when I do my tow in a couple of weeks. Your emissions are probably now on par with North American standards! I know our emissions control system lowers fuel economy a tiny bit. Follow up question - what kind of caravan are you towing and what is the weight?

Note that I was doing 100km/h with a trailer while regen was on to get that high temp. Once I backed down to 80km/h the temp stays around 600-650c.

Your cx5 is much 'younger' than mine, so all the carbon build up in dpf is definitely in a much better shape than mine. Hence, your EGT temp should be lower and dpf shouldn't regen as frequent as mine.

I have the caravelair Antares 335. With extras and customization(air conditioner, awning, larger fresh and grey tank, 8kw lithium battery and an extra bunk bed. I was told that it weights about 1,100kg
 
Interesting thread. I too have been playing with the ForScan app and recording data to get a better idea what is going on "behind the curtain" of my 2019 North American 2.2 diesel. You guys are seeing / reporting higher temperatures than I am seeing. (I realize you are both towing heavier weights than I am)

I did a 600 mile trip last weekend with about 750 lbs inside the car and towing around 1000 lbs. on a flatbed trailer. Outside air temperatures were 75-80 deg F. Rolling hills in Kentucky and Tennessee. Max temperatures I'm seeing during a regen cycle while towing at 70mph highway speed .... (all deg F)

EGT 1380 (Exhaust)
ECT 198 (coolant)
EOT 223 (Engine Oil)
TFT 207 (Transmission Fluid)
RDT 133 (Rear Differential Oil)

Tire PSI increase about 3psi to match the 30 deg F tire temperature rise.

I get about 200 miles per regen cycle which occurs when the Particulate Matter Generated (PM_GEN) reaches 6.00 g/L

Efficiency was about 28.5 mpg

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Just got back yesterday from an 1100 mile trip through Ohio and the mountains of West Virginia, Pennsylvania, Maryland with just 360 lbs in the car and not towing. Burnt 31 gallons for about 35.5 mpg. Temperatures very similar to the previous weekend loaded heavier and towing...

EGT 1400 max (Exhaust)
ECT 194 (coolant)
EOT 214 (Engine Oil)
TFT 193 (Transmission Fluid)
RDT 120 (Rear Differential Oil)

Front tires run slightly warmer than the rear. (They were more even when loaded heavier and towing)
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⋯ Tire PSI increase about 3psi to match the 30 deg F tire temperature rise.
So on tire pressure you follow North American Mazda recommended “one-size-fit-all” 35 psi all around, not higher pressures recommended worldwide, for heavier load and towing on your diesel CX-5?

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Interesting thread. I too have been playing with the ForScan app and recording data to get a better idea what is going on "behind the curtain" of my 2019 North American 2.2 diesel. You guys are seeing / reporting higher temperatures than I am seeing. (I realize you are both towing heavier weights than I am)

I did a 600 mile trip last weekend with about 750 lbs inside the car and towing around 1000 lbs. on a flatbed trailer. Outside air temperatures were 75-80 deg F. Rolling hills in Kentucky and Tennessee. Max temperatures I'm seeing during a regen cycle while towing at 70mph highway speed .... (all deg F)

EGT 1380 (Exhaust)
ECT 198 (coolant)
EOT 223 (Engine Oil)
TFT 207 (Transmission Fluid)
RDT 133 (Rear Differential Oil)

Tire PSI increase about 3psi to match the 30 deg F tire temperature rise.

I get about 200 miles per regen cycle which occurs when the Particulate Matter Generated (PM_GEN) reaches 6.00 g/L

Efficiency was about 28.5 mpg

View attachment 302990



Just got back yesterday from an 1100 mile trip through Ohio and the mountains of West Virginia, Pennsylvania, Maryland with just 360 lbs in the car and not towing. Burnt 31 gallons for about 35.5 mpg. Temperatures very similar to the previous weekend loaded heavier and towing...

EGT 1400 max (Exhaust)
ECT 194 (coolant)
EOT 214 (Engine Oil)
TFT 193 (Transmission Fluid)
RDT 120 (Rear Differential Oil)

Front tires run slightly warmer than the rear. (They were more even when loaded heavier and towing)
View attachment 302989
It seems that all the EGTs reported here are pretty consistent. @Coolpix99 reported 1382 F (750 C) max during regen which is the highest next to your 1400 F (760 C). Hopefully mine are in that range too.

I'm not an expert at this and can only tell you what I've read on google here and there. With that being said, I read this article and have been using 1500-1600 F (816-871 C) as a temperature to watch out for - EGT's Explained - How Hot is Too Hot? / Speed House Blog | Free Shipping | Best Price | Speed House
 
what is your boost pressure when towing?
I didn't have a PID set for boost pressure. I did earlier when I first started playing with ForScan and if I recall it was about 25 psi max boost that I saw just driving around (non towing).
 
So on tire pressure you follow North American Mazda recommended “one-size-fit-all” 35 psi all around, not higher pressures recommended worldwide, for heavier load and towing on your diesel CX-5? ...

Yes, of course. Those other parts of the world run tyres instead of proper tires. I don't hold my pinky out whilst I sip an espresso either 😜

Really though, I don't change pressure much. If I was towing maxed out in higher temperatures I would likely increase a few psi. I've been happy with tire temperatures, handling, even wear etc running about 36psi all the time.
 
It seems that all the EGTs reported here are pretty consistent. @Coolpix99 reported 1382 F (750 C) max during regen which is the highest next to your 1400 F (760 C). Hopefully mine are in that range too.

I'm not an expert at this and can only tell you what I've read on google here and there. With that being said, I read this article and have been using 1500-1600 F (816-871 C) as a temperature to watch out for - EGT's Explained - How Hot is Too Hot? / Speed House Blog | Free Shipping | Best Price | Speed House
I've found it interesting to read of your and Coolpix99 modifications for increased cooling. I appreciate you writing about it.

I'm no expert either (although I am a transportation professional, a "motivator of metal" 😁) but I'll put my trust in Mazda's engineers (at least while under warranty lol) and presume that my cx5 will operate within tolerances if I operate it as designed. I'm not going to make any modifications unless I have an indication that problems are developing (dash lights, warnings, throwing codes, power restrictions, UOA markers, increased regen cycles, etc).

I am curious and like to know more about what's going on in the vehicle and the ForScan app is a fantastic tool to see a lot of information for sure! It's great to see numbers of normal operation to compare to readings when something isn't right.
 
the ForScan app is a fantastic tool to see a lot of information for sure!
Can you tell us which version the ForScan you’re using and the link to purchase? And what kind of OBDII reader hardware setup with ForScan you’re using?
 
Can you tell us which version the ForScan you’re using and the link to purchase? And what kind of OBDII reader hardware setup with ForScan you’re using?

Just downloaded it off Google play store ...

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FORScan Lite for Android
v1.5.11
Kernel v2.3.41

The Bluetooth plug-in obdii port link is one of the recommended units from ForScan website ...

https://www.amazon.com/dp/ (commissions earned)

I also purchased the vLinker USB cable to run it from a Windows based laptop in the future (but you can break stuff with that!)
 
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