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Discussion Starter #1
After replacing my Radiator recently I decided I was going to send it to the recycler to gain a few bucks so before selling the aluminum Lets analyze how the radiator ATF warmer fails.


To my surprise the bevel spring was VERY RUSTED..


On both tubes.


The culprit is indeed the bevel spring, the stainless steel washer was in good condition.




So sad that this radiator failed... Look how pristine it was inside









ATF Warmer


The black O-Ring inside is the only thing preventing the Anti-freeze from leaking out of the plastic covers.


Surprisingly the ATF Warmer is the most complicated piece out of the radiator.
 

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Gasp, that is the same weakness in my 2005 model! Solo, they never fixed the problem with the next generation pilots and mdx... sad

the nipple popped off & thank goodness no mixing of the 2 fluids happened

I had installed a separate smaller stand alone atf oil cooler with cold weather valve and an aftermarket lifetime warranty radiator with pictures, but photobucket took down 3rd party hosting
 

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Discussion Starter #4
Yup.. Once the bevel spring loses tension there is only "not so very tight" threads holding the tube into the ATF Warmer..
Denso even applied Threadlock in order to avoid the tube to undo itself but once the main tension of the bevel spring is out ATF is allowed slowly leak into the radiator through the threads.

There is more detailed information of the failure here: Radiator comparison: Denso/Spectra/OSC - Honda Ridgeline Owners Club Forums
 

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wow that was a very informative thread. u still doing a writeup on this? ill be changing it out in the spring.
 

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Discussion Starter #6
Writing it as of now...
My current image hosting site is not very friendly so I have to review each picture and write the details as I go... I miss Photobucket :(
 

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Writing it as of now...
My current image hosting site is not very friendly so I have to review each picture and write the details as I go... I miss Photobucket :(
Photobucket sucks so bad. Try imgur.
 

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Great! Do you have a picture showing the tube from behind the stainless steel washer?
 

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Discussion Starter #10
Nope but its basically just a small threaded portion (that has red threadlock) and 2 O-Rings.
I don´t have the parts anymore since they went to the recycling center :(
 

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Nope but its basically just a small threaded portion (that has red threadlock) and 2 O-Rings.
I don´t have the parts anymore since they went to the recycling center :(
Here is a picture comparing the OEM design with an aftermarket design. May I ask a couple of very elementary questions?

1. Why is it necessary to have a Belleville spring (correct?) here? If this spring is eliminated and we screw the tube directly on the warmer, the top big nut will directly rest on the flat washer. What is the problem with this simpler setup?

2. For the aftermarket design, what is the purpose of the bottom big nut? Kind of the same question as the first one. I know.

Is it correct to say that the Denso aftermarket radiator is better than the OEM Acura radiator and various aftermarket radiators of other brands, and with the aftermarket Denso installed, there is no need to bypass the ATF warmer?
 

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Discussion Starter #12
1.- It needs the bevel spring because the threaded portion is not super precisely made and the tube has to end up looking at a specific angle so the ATF hose can go to the ATF Cooler.
So instead of wasting a ton of money making sure the threaded portion ends just exactly so that by the time the tube is tight is looking at the right direction? they used a bevel spring to make up for that lack of precision. The bevel spring tightens the tube when its looking at the right direction which is not exactly when the threaded portion ends (So you can in fact tighten the tube even more than where it is from the factory).
So the bevel spring and the red threadlock is what leaves the tube looking at the right direction.

2.- The aftermarket design solved the issue by actually fitting the ATF warmer into the radiator base instead of having the ATF tube doing double duty like the OE design.
The big nut in the aftermarket design has the sole purpose of holding the ATF warmer into the plastic portion while the secondary flare nut allows the tube do be angled to the precise OE spot it needs for the ATF Hose.

YES! Aftermarket DENSO uses the new updated design other afermarket radiators introduced to fix the ATF Warmer issue. So the OE Radiator is officially OUTDATED.
You will want the DENSO radiator as well because it retains the entire Heater Core stacks count, Others like Spectra or OTH uses LESS stacks (ex: 94 vs 120).
So the DENSO Aftermarket radiator is the ONLY way to go if you want to keep the OE Cooling Design while also updating the ATF Warmer setup to the fixed standard.
 
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1.- It needs the bevel spring because the threaded portion is not super precisely made and the tube has to end up looking at a specific angle so the ATF hose can go to the ATF Cooler.

So instead of wasting a ton of money making sure the threaded portion ends just exactly so that by the time the tube is tight is looking at the right direction? they used a bevel spring to make up for that lack of precision. The bevel spring tightens the tube when its looking at the right direction which is not exactly when the threaded portion ends (So you can in fact tighten the tube even more than where it is from the factory).

So the bevel spring and the red threadlock is what leaves the tube looking at the right direction.



2.- The aftermarket design solved the issue by actually fitting the ATF warmer into the radiator base instead of having the ATF tube doing double duty like the OE design.

The big nut in the aftermarket design has the sole purpose of holding the ATF warmer into the plastic portion while the secondary flare nut allows the tube do be angled to the precise OE spot it needs for the ATF Hose.



YES! Aftermarket DENSO uses the new updated design other afermarket radiators introduced to fix the ATF Warmer issue. So the OE Radiator is officially OUTDATED.

You will want the DENSO radiator as well because it retains the entire Heater Core stacks count, Others like Spectra or OTH uses LESS stacks (ex: 94 vs 120).

So the DENSO Aftermarket radiator is the ONLY way to go if you want to keep the OE Cooling Design while also updating the ATF Warmer setup to the fixed standard.


I finally found some time to take a look at the atf tube connections. It is very hard to see and I can only get an OK look at it with a mirror and a flashlight. It is impossible, to me, to take a good picture. But I am pretty sure that the Belleville spring is rusted. I saw two shinny silver pieces sandwiching a yellow piece. That is for sure.

So I am going to replace the rad in two years when replacement of the coolant comes up according to schedule. I am going to have my fingers crossed till then.

One more question. Is aftermarket denso’s design same as spectra or others? I think only spectra’s design is vastly safer than oem. For the others like koyo and osc, they are not that much better. Once the bottom nut gets loose, atf and coolant can mix as well.


Sent from my iPhone using Tapatalk
 

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Discussion Starter #14
Aftermarket Denso is BETTER than Spectra Now since it has the same double nut design as Spectra for the ATF Warmer so it completely eliminates any chance of ATF + A/F Mix up but uses the correct Stacked ATF Warmer design, Spectra uses a brass tube that is vastly different in design than OE.

From all the research I´ve made and the few responses on the Ridgeline Thread.
1.- Aftermarket Denso (The only option to retain the factory Heater core Stack count = OE Cooling Efficiency)
2.- Spectra
3.- OTH/Koyo
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.
99.- OEM.


Basically there is no incentive to go with anything BUT Aftermarket Denso...
Spectra offers a "Lifetime Warranty" but I´ve read online they will try their best to NOT honor it.
 

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I totally agree with your statement that Denso's coolant/ATF heat management is miles better than Spectra. However, because Spectra used a silly simple ATF warmer and it is brass, Spectra can engineer the warmer that a short portion of the tube receptacle will come out of the warmer directly. So there is no chance whatsoever for coolant and ATF to mix. All the others use the fancier decked ATF warmer design and the warmer will have a hole with female threads and the ATF tube will be screwed in and fixed by a big nut. Once that big nut fails, ATF and coolant can mix for all other design. So only Spectra is fail safe in this respect.

Since I never use my MDX very aggressively and many guys are using the Spectra in their RL and Ridgeline, I kind of feel that Spectra is not a bad choice. It is only $75 with free shipping. It is like 50% off Denso.

https://www.ebay.com/itm/Radiator-Spectra-CU2938-/162852834113?_trksid=p2385738.m4383.l4275.c10

BTW, have you checked the price on RockAuto again? The Denso is back to 116 now. You got screwed.:(
 

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Discussion Starter #17
But the big nut cant fail..
Its threaded all the way into the ATF warmer, The idea of separating both is so that the big Nut can finally be threaded all the way in. Thus this design does not have a bevel spring just a simple washer and O-Ring.

Even if the nut became heavily rusted nothing will make the big nut to undo itself so ATF and A/F mixture is next to impossible..
 

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Well my experimenting on bypassing the ATF portion with just a tube for the winter has been going good so far for us frigid folks. No weird characteristics or any issues running in 0deg F temps. I plan to put in a proper ATF cooler in the spring. But in the mean time, it shifts fine and no slipping or anything in 0 degree temps with the bypass.
 

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Discussion Starter #19
If anything at cold it "Could" just do hard shifts or lower MPGs due to thickness... To Slip it should be extremely hot, Cooler ATF its better for the clutch packs.
The main source of heat for the ATF is the Torque Converter which is a small furnace, The ATF warmer in extreme cold will be just to the maintain proper ATF Temp but considering its on the radiator the ATF warmer will probably freeze in the radiator rather than "Warm" anything anyway.
 

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Hi Skirmich, you have written such opinions many times. However, the same setup is not only used in Honda. I can see that Toyota and Nissan all use the same setup in many, many of their vehicles. So when you make such claims, your counter-party is actually all the engineers in Toyota/Honda/Nissan. If letting ATF go through radiator is such a bad idea, the natural deduction is that all these engineers are all collectively dumb. But I found this conclusion is hard to believe. There must be some good reasons it is designed this way. You, as well as me, are not aware of it.
 
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