Acura MDX SUV Forums banner

1 - 20 of 30 Posts

·
Registered
Joined
·
172 Posts
Discussion Starter #1
I rebuilt my trans last week, new steels and frictions, new seals. I noted that second gear had gotten hot and blued the steels. I will be installing a trans cooler. Question is should I bypass original radiator cooler or go inline with it? Radiator was replaced couple years back after old one leaked. Did Honda/Acura do an updated radiator?

Sent from my XT1585 using Tapatalk
 

·
Registered
Joined
·
172 Posts
Discussion Starter #5
Like 400 bucks, no hard part's needed other than steels and frictions

Sent from my XT1585 using Tapatalk
 

·
Registered
Joined
·
400 Posts
Like 400 bucks, no hard part's needed other than steels and frictions

Sent from my XT1585 using Tapatalk
Darn you are a real mechanic to be able to take apart your transmission. If I ever attempted that, I am sure I would be left with lots extra parts! :)

I changed my leaking radiator and bypassed the internal rad cooler. I also popped on a large external cooler. I have read that MDX drivers in colder climates should consider using the rad cooler to help normalize the temperature more quickly. However, I live in florida so that is not a concern. In my view we are already dealing with a flaky transmission. I am not going to expose it to another risk.
 

·
Registered
Joined
·
172 Posts
Discussion Starter #7
That's what I'm considering, it's real cold here in Wisconsin, I know the rad. Was replaced relatively recently, was wondering if Honda addressed issue on newer radiators...
Thanks for the compliment. I rebuilt a tranny for my full size bronco and motorcycle transmissions, do what the hell, I'll give this one a go. Similar principals throughout... Lots to keep track of though, and a couple special tools needed, but doable. I rebuilt the engine as well, so should run like new.

Sent from my XT1585 using Tapatalk
 

·
Registered
Joined
·
400 Posts
I cant answer the question whether Honda upgraded the radiator. Mine started leaking at another spot at about 150k which caused me to change it. However when the mechanic took it out, the failure symptoms of internal rad cooler were present and eminent. The connectors were rusted and broke off when trying to take off the hose.

If I was living in Wisconsin I think I would have utilized the internal one plus an external one and would also change the rad at maybe 100k intervals. BTW I replaced mine with a denso aftermarket radiator that was about half the price of the OEM. I think I paid like $125.

I go back to my point about these finicky transmission. I try to baby sit these guys to hopefully minimize a failure
 

·
Registered
Joined
·
2 Posts
How about adding a tow hitch?

Hi All,
Can I jump in with a related question? I'm going to add a tow hitch to my '04 MDX to pull only a small trailer with dirt bikes, should I install a transmission cooler as well? I'm in CA so weather is fairly warm with no extremes, although we drive in snow in winter.
Seems there is the radiator and then a smaller external one as well? There is two units. Thanks.
 

·
Registered
Joined
·
172 Posts
Discussion Starter #11
I would say absolutely. I'd recommend it on non towing rig with Honda trans

Sent from my XT1585 using Tapatalk
 

·
Registered
Joined
·
2 Posts
Thanks, much. I am not sure if there is one on or not. It looks like two units, do you know if there would be two radiators if a stock trans cooler came on the X?
 

·
Registered
Joined
·
172 Posts
Discussion Starter #13
Follow the lines from the trans, two black rubber hoses. They should go to the bottom of the radiator. If there is another cooler, they will come out of the bottom of the radiator and one will go to another small radiator visible through the grill maybe like one for by one foot in size, then a house will return from that to the trans


Sent from my XT1585 using Tapatalk
 

·
Registered
Joined
·
3,337 Posts
I wonder why people get the idea that the Radiator ATF Cooler will Heat the entire transmission ATF in Cold Weather?? Radiator will freeze, if anything it will cool down the ATF when driving which its main job.

Little they know the MAIN SOURCE OF HEAT is the TORQUE CONVERTER! Just slide the gear lever to 2nd and start driving a little, You will get to full heat in no time.
 

·
Registered
Joined
·
172 Posts
Discussion Starter #15
Clearly, I think it's more about regulating temp, in theory, shouldd keep it close to thermostat temp after warm up (in theory,anyway)

Sent from my XT1585 using Tapatalk
 

·
Registered
Joined
·
3,337 Posts
It should take a really long time for the T-Stat to open up in the freezing states for the Engine.. More likely the Radiator ATF Cooler is over cooling the ATF most of the time.

Here in SoCal the internal ATF Cooler can only do harm... Specially considering that the engine is making the Anti-Freeze boil up, The last thing you want is the ATF Cooler being inside the radiator when outside is 120°F.

The radiator problem and that was my main reason to completely by-pass it.. So far it has been great I rarely see the ATF Cooler go above 60°C Under normal driving conditions, When doing Off Road and Steep Climbs using only 1st and really pushing it I have yet to see it break 70°C. Vs Seeing 80°C/93°C on the Stock Setup.
 

·
Registered
Joined
·
172 Posts
Discussion Starter #17
You would actually be suprised how quick the t-stat opens in cold weather within 5 mins usually, cause that's how long it takes for heat to start working. I agree external cooler is probably best, but there has to be a redeeming quality to running it in the radiator because many, many manufacturers do it. I don't think the factory setup is for cooling as much as it is for warming, but just a guess on my part.

Sent from my XT1585 using Tapatalk
 

·
Registered
Joined
·
400 Posts
The radiator problem and that was my main reason to completely by-pass it.. So far it has been great I rarely see the ATF Cooler go above 60°C Under normal driving conditions, When doing Off Road and Steep Climbs using only 1st and really pushing it I have yet to see it break 70°C. Vs Seeing 80°C/93°C on the Stock Setup.

I was torn on this decision but in hindsight it was a good one to install an after market cooler. I bought one for less than $100 from Advance Auto and paid another $50 to install it. Even after towing a boat I can touch my external transcooler with my finger for a few seconds. It is hot but not ridiculously hot.

There was a poster sometime back who recorded the temperature before and after installing the cooler and noted that the biggest difference came when the fan was off. The moral of the story for me is this: having an external cooler is great but it is more important to keep the AC running so those fan stay on even in cold weather.
 

·
Registered
Joined
·
3,337 Posts
You would actually be suprised how quick the t-stat opens in cold weather within 5 mins usually, cause that's how long it takes for heat to start working. I agree external cooler is probably best, but there has to be a redeeming quality to running it in the radiator because many, many manufacturers do it. I don't think the factory setup is for cooling as much as it is for warming, but just a guess on my part.

Sent from my XT1585 using Tapatalk


You are right, In fact the ATF Cooler is referred as "ATF WARMER" in the Service Manual so it is not there to keep things cool but rather to warm up the trans faster... I get the impression of cooling since its in the lower part of the radiator which is the cool side.

I believe its done for MPG reasons, in the colder climates trans takes a lot of time to reach operating temp so it tends to hold up the gears for too long.. The 2G MDX has this feature built in, if you take off without warming the car up you will notice the gears tend to be held for the first couple of driving minutes. Then its all shifting good when the engine reaches operating temp.


I was torn on this decision but in hindsight it was a good one to install an after market cooler. I bought one for less than $100 from Advance Auto and paid another $50 to install it. Even after towing a boat I can touch my external transcooler with my finger for a few seconds. It is hot but not ridiculously hot.

There was a poster sometime back who recorded the temperature before and after installing the cooler and noted that the biggest difference came when the fan was off. The moral of the story for me is this: having an external cooler is great but it is more important to keep the AC running so those fan stay on even in cold weather.
I have always used ATF Coolers in my AUTOs here in SoCali.. Is simply a NEED with our summers.. Also Honda/Acura trans are very susceptible to heat so better not push my luck, Both of my cars have them and also my wifey Bimmer.
 

·
Registered
Joined
·
172 Posts
Discussion Starter #20
I've concurred that I will be bypassing the radiator and using a stack plate tranny cooler and a magnefine magnetic inline transmission filter, fyi. Just got the engine tranny joined and into the subframe.... Ready to reinstall in car

Sent from my XT1585 using Tapatalk
 
1 - 20 of 30 Posts
Top