Is a B&M 70264 external transmission oil cooler more efficient than OEM?

StreetCreeper

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I have a B&M 70264 oil cooler I plan to install tomorrow on my 1997 Ltd. While I have not experienced any tempeture issues before, I am in a 97 so I can't really see my tranny temps.

I'm installing the B&M cooler to avoid the pink milkshake, however, I am curious if anyone knows how the B&M 70264 cooler actually cools in comparison to the original cooler?

The liturature I have read from B&M suggest running the cooler in series with the original and only running the cooler by itself if the original is absent or damaged. Obviously running it in series with the original defeats the point when trying to avoid the milkshake. But now I'm curious if my temps will run higher with the B&M alone.

I am planning a trip to SoCal on Friday and want to get the cooler on before I head over the grapevine—but now wondering if I should hold off until after the trip since I'm not sure what will cool the oil better climbing those grades.

Anyone compared before and after temps?
 
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No idea about the 97 pink milkshake issue but it goes without saying 2 coolers will yield a lower temperature than just one. That being said, the B&M by itself will do the trick just fine when mounted correctly. Do a Google search you'll see.
 
No idea about the 97 pink milkshake issue but it goes without saying 2 coolers will yield a lower temperature than just one. That being said, the B&M by itself will do the trick just fine when mounted correctly. Do a Google search you'll see.

Yes but I'm only installing it to avoid a milkshake—not because of pre-cooler temp issues. I've read the installs and know where I'm going to mount it for maximum efficiency, but I've never seen any before & after data on the temp difference when ran alone.

I'm fairly confident that it is sufficient to avoid immediate damage to the transmission, but that still doesn't mean it is actually doing as good-as or better job than the original cooler, i.e., are we actually taking a hit on cooling abilty when switching to the external cooler alone just for the insurance of not mixing a pink milkshake.
 
I would say as long as you're moving it is as good if not better than oem. When idling the radiator blocks a lot of the fan airflow so it could not be as effective, this is why some opt to run both... If your worried about the pink milkshake only I'd invest in a new radiator before an aux b&m cooler
 
I'm not sure I can add any beneficial information here, but I have read that running both the oem and aftermarket coolers in series is counter productive. The oem cooler uses the heat from the radiator to bring the transmission fluid up to operating temperature and attempt to hold it there. Installing a second transmission cooler in series will work against what the oem cooler is trying to do.

I also heard that the B&M cooler has a valve in it that keep fluid out of the cooling portion until the fluid has reached a specific temp, so I could be counterdicting myself.
 
... I've never seen any before & after data on the temp difference when ran alone...

When I was running stock, after the transmission would get up to temp, it would range anywhere from ~170°F to ~190ish (but would get hotter if I pushed it).

After doing the B&M 70264 bypass, the temperature became much more dependent on the outside ambient temperature. It warms up to approximately 80° - 100°F over ambient temp for the normal low operating temperature (flat highway driving at constant speed.) However, it is more susceptible to getting hot when pushing it over extended periods. Stop and go and accelerating to keep up higher speeds when going up overpasses would bring trans temps over 200°F without too much effort. But, it will rapidly normalize back to ~100°F above ambient when the torque converter locks up, at least on the highway.

EDIT: The characteristics of this may change since I'm pretty darn sure that my trans pan needs to come down and the filter needs to be cleaned out due to delayed/late 1-2 shifting characteristics when the fluid hasn't warmed up.
 
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When I was running stock, after the transmission would get up to temp, it would range anywhere from ~170°F to ~190ish (but would get hotter if I pushed it).

After doing the BBM 70264 bypass, the temperature became much more dependant on the outside ambient temperature. It warms up to approximately 80° - 100° F over ambient temp for the normal low operating temperature (flat highway driving at constant speed.) However, it is more susceptible to getting hot when pushing it over extended periods. Stop and go and accellerating to keep up higher speeds when going up overpasses would brings trans temps over 200 without too much effort. But, it will rapidly normalize back to ~100° F above ambient when the torque converter locked up, at least on the highway.

What did you measure this with out of curiosity? Scangauge II?
 
IMHO save your pennies and buy another radiator, then put the B&M in series with it for maximum cooling efficiency.

If going alone with the 70264, make sure your fan clutch is operating well.
 
No before and after temps but Ive been driving across the country towing a 6x10 trailer with dirtbike and plenty of other junk for a little while now. Ill be driving back to california from texas next week then to colorado in a few weeks so I can update again.

I have the Hayden 687 Look similar. rarely do I see temps over 200 but they have gone over 200 shortly. turning overdrive off drops the temp more than anything. once I click it off temps drop almost instantly. scan gauge used to temps
 
Before my trans cooler bypass, the trans ran the same as the engine - about 194-199, even on mountain passes. Now with only the external cooler, it does run cooler, for a while, then eventually (45 mins of highway or 30 city) makes it up to 195. But on mountain passes (like west texas or southern Cali) it will get up to 230 if I don't turn over drive off. With OD off, it quickly settles back to 195-199. I'm thinking Toyo had the right idea by warming up the trans fluid quick and holding it there. On the flipside, I haven't heard of anyone having trouble because the temps fluctuate more now. Hmmmm.
 
In conclusion is it worth installing the B&M cooler? Is it beneficial at all? Still can't seem to make a decision after reading the comments above!
 
...EDIT: The characteristics of this may change since I'm pretty darn sure that my trans pan needs to come down and the filter needs to be cleaned out due to delayed/late 1-2 shifting characteristics when the fluid hasn't warmed up.

I experience this as well! So you think it's just a dirty/old filter that causes this? Or is this a symptom of a larger issue?
 
sounding like the hot setup is to just put that money into a new radiator instead?

This is what I did. Got around 100k miles on my original radiator and bought a new Denso one. For something as significant as cooling, I figured on staying with how Toyota designed it, seeing as they do just fine, minus the pink milkshake issue (hence just replace the radiator every 100k miles or so).

I'm from an area with extreme temps, so all the more reason for me to stick with the original design.
 
after inordinate quantities of hours reading about the radiator / trans cooler / milkshake thing, I've decided to simply consider the radiator as a maintenance item and just replace it at 120k service intervals. i suspect that parts for these trucks will start getting scarce soon, so I'm typically purchasing multiple units of replacement items and just stashing the extras until the time comes. seems about right until I start hauling boats again and need to consider non-OEM mods.
 

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