Transmission cooler: to by-pass the radiator or not to by-pass it

[Pikeman]

. Googling for text that supports an argument is not science.

Correct it is not science... it is research. While the interweb is full of eronious information, there is as much or more valuable information out there. I read many articles from reputable sources before making my decision and basically outlined that decision making process in my post so that others can make an educated and informed decision of their own. Also while it disputes some of what the OP said it also supported some as well.

We all need to keep posts to helpfull information and not long drawn out pissing contests. This will aid others getting good information when they search instead of having to read through dozens of combative posts. Remember scientific facts, tech articles(googled for support) and first hand experience are all good sources when substantiated.

BrianEMC thank you for stating why you made the decision you did and not adding to the pissing contest.

 

[quicksilvr]

But....this pissing contest was hilarious.

If nothing, it at least got the thread more posts and views and more mentions of the key words, so it'll show up in a search easier.


I appreciate this forum for it's ability to be reasonable, and un-douchebaggy.

 

[Drcoffee]

I didn't read all of this thread but I do want to mention one thing as I work in the auto industry as a engineer.

A lot of things are designed to work and mainly to keep the cost of the vehicle down. Integrating the rad and trans cooler in one unit is mainly to reduce cost, parts instalation, tooling, quality and supply chain.

Do not believe this is superior because toyota designed it. It works and its proven and a lot of vehicles use the same design. But look at any performace offroad or racing vehicle and it will have seperate cooling systems because reduction in cost is not a primary goal.

Steve240, I appreciate you input but keep in mind a manufacturer designs a vehicle to work in all type of climates. A performance vehicle is purpose-built. A race car is constantly being adjusted for the race day. Even a temp drop of 10 degrees will have the pit crew readjusting the settings. They may run external coolers but they are specific for an 80 degree day with sun or clouds, etc. Who here sets up their car each day before heading to work. Yes, its a cost savings to integrate the two coolers but it also helps narrow the operating range the truck will be working within. You may be driving in AZ in 110 degree day but your transmission is running at 190 degrees or you could take the same truck to the summit and still the transmission will be at around 120 degrees. That's just something a single B&M cooler rated at 14,400 GVW won't be able to modulate.

In short, no racing chief mechanic would, in his right mind, setup the cooling system for his performance vehicle the exact same way for a desert run and a winter run. But some here are telling other members to do just that.

 

[tbst]

I agree with everyone who replaces their radiators with new OEM ones. It's basic maintenance.

The issue was and is that Drcoffee asserted that anyone who didn't have the extra $70 to throw down on a new radiator and instead spent $50 on a tranny cooler was stupid. That assertion is what I take issue with.

Along with the fact that he has 0 data and has trolled everyone who responded to him after asking once for his data, myself included.

Bottom line: He is a troll and we let him troll us.

 

[Drcoffee]

Now to point that external coolers will not let your transmission warm up properly. Most coolers are mounted to the front of the radiator and will be warmed from the radiant heat from coolant. Also the better external coolers (B&M, Tru-cool) are a low pressure drop design with low temp bypass. meaning that when the fluid is cool and thicker it will bypass the cooling ports and flow through the bypass until it heats up and thins enough to go through. If you buy an aftermarket cooler without the thermal bypass built in then you can also add an external thermal bypass(alot like a thermostat does for your radiator). Transmission coolers are rated by GVW and also BTU(British Thermal Units) just like the burners on a oven etc. so various sizes will cool a different amount then the arbitrary 20 degree stated.

.

Way too much to pick it all apart. Lets start here. So you say the radiatnt heat from the front of the radiator will actively warm the B&M? Think again. The cooler is about 4-5" away from the radiator, which if you open your hood, you would see the AC condensor infront of the radiator, which as a matter of practice is not typically running in the winter. Yes it can be engaged with the defroster but the fact remains, it is not in close proximity to the radiator. Compounding the issue with radiant heat, is the fact you have a mechanical radiator fan sucking cold air over the B&M constantly. You'd be smoking crack in order to imagine any radiatnt heat moving forward to the cooler.

We can talk in BTUs or GVW(which is really meaninless). BTU is thermal efficiency in a numerical way. Who here has a clue what BTU equates to when discussing radiators? So to keep this thread understandable to the average member or visitor, I discuss the efficiency in terms of "potential temperature drop between inlet and exit of the cooler. We can all grasp a 20 degree drop. You tell me. Is that a 15,000 BTU drop or 5,000 BTU drop. Lets not get stuck in engineering jargon. If you send 200 degree oil in and out comes 180 degree oil, we can all understand that.

On a side note, when you think of thermal efficiency of you car's AC, regardless of the outside ambient temp, the tech is measuring the difference between ambient and vent temp. That's why they added recirculate to the HVAC. It lets you cool from a lower starting point rather than whatever the outside temp might be.

Back to the topic at hand. The low temp, low pressure drop feature some (not all) coolers have will shunt oil past the cooling fins to allow it to warm quicker when in series with the radiator. Why do they do that? Marketing? maybe. More to the point, it's because they understand that cold trans fluid is damaging to the transmission. They want to get the temp up to operating conditions quickly and then maintain it there for best performance. Why? Because the transmission was designed to work within a certain temp range. But tsbt is smarter than the engineers at B&M as well.

 

[Drcoffee]

I agree with everyone who replaces their radiators with new OEM ones. It's basic maintenance.

The issue was and is that Drcoffee asserted that anyone who didn't have the extra $70 to throw down on a new radiator and instead spent $50 on a tranny cooler was stupid. That assertion is what I take issue with.

.

There's that great movie line from Forest Gump...


"Stupid is as stupid does."

tbst, you do know how to use google, don't you? Look it up for yourself.

And No! you don't agree with anyone who just replaces their radiator with a new one. You have said this, "yes change your radiator but then also bypass it" Don't start back-peddling now. You would be telling an untruth.

 

[quicksilvr]

Yes, its a cost savings to integrate the two coolers but it also helps narrow the operating range the truck will be working within. You may be driving in AZ in 110 degree day but your transmission is running at 190 degrees or you could take the same truck to the summit and still the transmission will be at around 120 degrees. That's just something a single B&M cooler rated at 14,400 GVW won't be able to modulate.

In short, no racing chief mechanic would, in his right mind, setup the cooling system for his performance vehicle the exact same way for a desert run and a winter run. But some here are telling other members to do just that.

And this goes on. If you keep posting, we're going to keep correcting you.

A single B&M external cooler almost 100% mirrors the temps provided from the factory cooler. In fact, the external cooler's range is SMALLER than the internal coolers. Not much, but slightly. ATF doesn't get quite as hot in hot/hard working conditions, and and it stays slightly warmer in cold conditions.

I can say this, because I have seen the temps. Day in, and day out....for over a YEAR.


Please.....PLEASE for the love of everything sane.....stop posting stuff that is incorrect, thus making me (us?) obliged to correct you.

 

[quicksilvr]

Back to the topic at hand. The low temp, low pressure drop feature some (not all) coolers have will shunt oil past the cooling fins to allow it to warm quicker when in series with the radiator. Why do they do that? Marketing? maybe. More to the point, it's because they understand that cold trans fluid is damaging to the transmission. They want to get the temp up to operating conditions quickly and then maintain it there for best performance. Why? Because the transmission was designed to work within a certain temp range. But tsbt is smarter than the engineers at B&M as well.

Dude, you are on crack. Like, the really good internet stuff.


And to think Pikeman actually had the decency to respond with a very "nice" tone, trying to keep this whole discussion reasonable. Sorry Pikeman, it didn't work.

Can we get back to this pissing contest? I honestly think it will be helpful for new members and people addressing this issue....they can see two sides to this discussion, and be entertained at the same time.

 

[tbst]

There's that great movie line from Forest Gump...


"Stupid is as stupid does."

tbst, you do know how to use google, don't you? Look it up for yourself.

And No! you don't agree with anyone who just replaces their radiator with a new one. You have said this, "yes change your radiator but then also bypass it" Don't start back-peddling now. You would be telling an untruth.

Forest Gump...Excellent movie. You have said that quote in five or so threads. Get some new material. It really really isn't that difficult. And wait...Before you come back saying I like to be fondled by sweaty women at the airport like you did a few threads ago (makes no sense), think of new material.

Don't start putting words in my mouth. Someone asked a few tedious pages back if they should skip their radiator or not and I said that skipping it would ensure never getting the pink milkshake. Which is a fact, unlike anything you have said.

I am really perplexed on how little you know about anything related to this and anything related to vehicles at all.

Do you know the steps in the scientific theory?

I would really check this out.

Scientific theory - Wikipedia, the free encyclopedia

You have the hypothesis part down, but you are missing the observations and experiments part.

Still waiting on your data set.

 

[opie74]

Ive always installed aftermarket coolers in my vehicles. This 2001 runner was no different. I acquired it in Feb of this year and quickly added a cooler. Prior to the cooler, I watched how the trans warmed and cooled, stock, via the ScanGuage. I noticed it warmed quickly and temps would fluctuate quite a bit between TQ lock and unlock with it cooling quickly once the TQ locked up at 48MPH. With temps between 15 and 20 degrees, the trans would warm to around 105 during my 3 mile trip to work. After the cooler was installed and bypassing the radiator, under the same conditions the trans would behave identically. However, since I never approach the speed needed for the TQ to lock up during my drive to work, I never saw the difference between stock and after. So one weekend I did my normal drive to work, got the tranny up to about 113, and hit the highway. Tranny went up to 122 or so, and then quickly dropped to 97 after TQ lock up. The climbed a bit to around 101 and stayed there while cruising 70 on the highway with ambient temps right around 20. Now, with ambient temps around 70, it hoovers around 135 on the highway and between 160 and 170 with all city driving.

 

[Drcoffee]

Don't start putting words in my mouth. Someone asked a few tedious pages back if they should skip their radiator or not and I said that skipping it would ensure never getting the pink milkshake. Which is a fact, unlike anything you have said.

Still waiting on your data set.

That's a distinction without a difference. The Clintonian way of speaking only works when you need votes. Everyone else can see through the veiled parsing of words.

Haven't you noticed that in 80+ posts that NOBODY and I mean NOBODY has chimed in and said, Heck yes, I'm deleting my radiator cooler today. What a great idea. Instead its the same 5 or 6 lemmings who need to prove their case over and over again.

What I've read is more on the lines of; I've been following this thread and after serious consideration, I'm not deleting my radiator cooler, but I will buy a new radiator.

tbst, I'm not here to learn you anything. When I joined T4R.org I quickly realized that for a small group of cultists proffering bad advice were head-stong in their beliefs. Why on this green earth do you think I titled the thread as I did? My whole intent was to "caution" others from making uninformed choices based on internet hype. You are big boy. Do your own research and come to your own conclusion for your own truck. It sounds like you already have and I wouldn't be so foolish to waste any effort on that futile adventure.

BTW I still chuckle at the sweaty TSA woman comment. It's one of those pictures you just can't get out of your mind. The smile on your face, I mean.
:lmao:

 

[tbst]

Like I said before I wouldn't be smiling with your wife touching me. Disgusted is more like it.

If we are going to talk politics, this thread definitely needs to be closed.

Still waiting on your data though.

 

[opie74]

I deleted my radiator cooler.

But not because anyone told me to. Because I always have, in every vehicle I own. Common sense dictates the cooler you can keep the fluid, the longer everything will last. Sizing the external cooler properly and bypassing the cooler in the radiator is a no brainer.

 

[pdx650]

In short, no racing chief mechanic would, in his right mind, setup the cooling system for his performance vehicle the exact same way for a desert run and a winter run. But some here are telling other members to do just that.

I don't know many other forum members, but I doubt any of them have racing cars. So, your point there is irrelevant.

 

[Millerad1651]

I also deleted my stock radiator cooler. My father has done external coolers in the last 5 vehicles he has owned. I, because of him, have done the same in the last 3 vehicles I owned. I did this to my 4Runner before I joined T4R.org, because i knew it would positively affect my vehicle...just because we don't chime in the fact that you're wrong doesn't mean we don't participate in the cooler bypass mod/upgrade...so speak for yourself, not me.

 

[mforce]

This again today has been good popcorn reading. I have decided start looking at a new radiator for mine since it probably has not been changed and I have almost 170K on it. It will be living in a hot climate possibly AZ and has spent most of it's life in the south so no millkshake here but I don't want one. But with that said I still like the idea of a separate cooler like B&M as I have always had one on my trucks/suv's.

 

[Socco]

Compounding the issue with radiant heat, is the fact you have a mechanical radiator fan sucking cold air over the B&M constantly. You'd be smoking crack in order to imagine any radiatnt heat moving forward to the cooler.

Umm... Radiation, as a means of heat transfer, is not affected by wind.

BTU is thermal efficiency in a numerical way. Who here has a clue what BTU equates to when discussing radiators? So to keep this thread understandable to the average member or visitor, I discuss the efficiency in terms of "potential temperature drop between inlet and exit of the cooler. We can all grasp a 20 degree drop. You tell me. Is that a 15,000 BTU drop or 5,000 BTU drop. Lets not get stuck in engineering jargon. If you send 200 degree oil in and out comes 180 degree oil, we can all understand that.

You cannot generalize that a cooler always sheds 20 degrees. :bash: The "degree drop" depends mainly upon the velocity of the fluid passing through the cooler and the temperature difference of the fluid in the cooler vs. the air going across it. This is why they are rated in BTUs. The BTU rating is the maximum amount of heat that the cooler can reject, under any circumstance. "Engineering Jargon?" How about reality?

Haven't you noticed that in 80+ posts that NOBODY and I mean NOBODY has chimed in and said, Heck yes, I'm deleting my radiator cooler today. What a great idea. Instead its the same 5 or 6 lemmings who need to prove their case over and over again.

Heck yes, I deleted my radiator cooler last year. What a great idea.

My decision to bypass the rad was not forced upon me by the head-strong, cultist, lemmings of the internet. Rather it was a concept that was highly recommended to me by persons, who's opinions I trust. These included: A Heavy-Duty mechanic with +40 years in the field, A transmission specialist / shop owner with +40 years in the field, A fleet supervisor with +30 years in the field, A race car driver and a mechanic who has specialized in high-performance for over 40 years.

 

[Qyota]

"lemmings" eh? Good luck getting help around here, doc.

Hey doc, what is this "optimal temperature range" of which you speak? I mean, for as much as you talk, you gotta know...right? Optimal temperature range for the A340F transmission, under ALL driving conditions and ALL air temperatures. Please tell us, so we know where we "should" be. Oh, and don't forget to back up your range with data specific to this transmission. Thanks, we all appreciate it!

 

[brian4t]

When I joined T4R.org I quickly realized that for a small group of cultists proffering bad advice were head-stong in their beliefs. Why on this green earth do you think I titled the thread as I did? My whole intent was to "caution" others from making uninformed choices based on internet hype. You are big boy. Do your own research and come to your own conclusion for your own truck. It sounds like you already have and I wouldn't be so foolish to waste any effort on that futile adventure.

Until now I've mostly stayed quiet here on TR4 other than a few simple questions, however, this comment above got me thinking. It seems apparent through your big words but blatant grammatical errors this 'cult' has you a bit butt hurt, on the defensive if you will. Your caution, advice and (so far) unsupported theory are ALL your opinion. What this 'cult' has advised is simple. Delete all possibility of coolant mixing with transmission fluid, it works. Whether your transmission runs cooler for longer or vise versa is up for debate. I can tell you from my experience anything over 100K on transmissions is icing on the cake, take it and run. This debate over reducing the life of your transmission from 300K to 250K is ridiculous and you know it. You're paragraph above proves your trolling ability and quite frankly gives no credence to your argument and clearly depicts you as a troll.

If you're so confident this cult exists here then why not find another forum? While you're at it buy some of this.

Red Line Synthetic Oil - Automatic Transmission Fluids - High-Temp ATF

 

[ALBPM]

:snacker: