Which aux trans cooler to get.

Discussion in 'Automatic Transmission' started by Dutch Rutter, Mar 11, 2018.

  1. Rusty Nail

    Rusty Nail Build the wall - deport them all!

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    Google is full of them.

    I searched "more transmission fluid improves cooler efficiency" before posting this Mr. "not difficult". :rolleyes:
     
  2. 87scotty

    87scotty Full Access Member

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  3. Dutch Rutter

    Dutch Rutter Full Access Member

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    @Rusty Nail Sorry about me misunderstanding what you were saying. Could be i received a faulty unit or something along those lines.

    Cooler came in last night. Got it all installed. Great unit, feels really solid. On the way into work this morning the trans seems to have been shifting crisper, and smoother. I would doubt this is actually because of the cooler and is probably just my butt-dyno acting up a little, but I feel more confident in this setup so far. Haven't driven in heavy traffic or a hot day yet either so we will see how it does.
     
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  4. Honky Kong jr

    Honky Kong jr Super Sarcastic Man

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    Oh no it’s the cooler... I guarantee it.
     
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  5. 77 K20

    77 K20 Full Access Member

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    I've heard you should run thru the external cooler first then go thru the radiator cooler if you live in a cold climate. That way the radiator will warm the fluid a little bit before returning to the transmission.

    If you went thru the radiator first and then the aftermarket cooler second wouldn't that just cool off the fluid too much again? In the winter here it gets as low as -20 degrees. If the outside temperature was zero then what would the ATF cool off to?

    Perhaps I've just been misinformed before, but it made sense to me. What is the reasoning running them in the other order?
     
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  6. Rusty Nail

    Rusty Nail Build the wall - deport them all!

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    No worries, we're all in this together. Teamwork gets more done better!
    I think the cooler too but I have a theory that I practice for many, many moons...wanna hear it?

    You and I both know that the vast majority of drivers neglect transmission maintenance and THAT is HOW and WHY I thought this up!
    In short: I believe that automatic transmissions find GREAT BENEFIT in new fluid, even a little bit. When possible back in the day for my customers I would unscrew a transmission line from the radiator and pump out a quart or so only so I could install that much new fluid. In my experience that gives the transmission (fluid) a real boost and helps to circumvent the lack of routine fluid and filter changes.
    Yeah sure the cooler IS working and I don't want to downplay that but other factors at play such as increased capacity and the amount of NEW additives introduced should be considered as well. :imo:


    @77 K20 I agree and believe that is sound logic. Additionally in hotter climates and/or given more stop and go traffic/idling time, heat transfer from the coolant to the transmission fluid is a very real thing. Considering with the amount / duration of highway driving (read: cooler trans temps) the driver is best suited to determine which order is best for them in which vehicle, yes? We don't see -20 in Oklahoma! :D

    My SS only runs very hard my C20 only sees stop and go and my Blazer idles for extended periods but it's cooler isn't even installed but it'll go last with the coolest temp possible fluid returned to the trans, as stated above, they are all that way..:badger_1:

    20180315_191320.jpg
     
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  7. 77 K20

    77 K20 Full Access Member

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    Thanks for the reply Rusty- I just wanted to make sure I wasn't missing something.

    I'm due to service my trans soon... so a cooler is on my list and then I made the mistake of researching ATF about a month ago.

    Hate to open a can of worms (and perhaps this isn't the time or place)... but what is popular out there with you guys? So far I've seen about half on other websites that say Type F and then the others say get "older" Dextron III or equivalent. The newer Dextron's are not that good for older transmissions.
     
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  8. Honky Kong jr

    Honky Kong jr Super Sarcastic Man

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    Type F is what use
     
  9. Rusty Nail

    Rusty Nail Build the wall - deport them all!

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    What transmission are you using?

    I use the manufacturer recommended Dex3 in my th-350 , my th -250, and will use that in the th-400 I bought.

    Hope this helps!
     
  10. 77 K20

    77 K20 Full Access Member

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    TH350

    I do a lot of rough trail rides- so slow speed stuff. 30 mph or less. Often in 2wd low or even 4 low.
    I’ve kept my mechanical fan for that reason. My engine never gets warm but suspect the trans isn’t liking it sometimes.
     
  11. Dutch Rutter

    Dutch Rutter Full Access Member

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    With your low ground speed it might be worth while to place an e-fan onto the trans cooler, in addition to your mechanical fan. I have this so that when I'm in stop and go traffic I can press a button and see the trans drop about 10-20 in a few minutes. While still being stopped.

    I also should have noted this is running brand new fluid but @Rusty Nail That is a great idea! I've read people not recommend changing fluid completely in older more neglected tranmissions because it will loosen junk or loose the particles from the fluid which will cause it to break down. But this
    Would get new fluid in while also keeping that other stuff as well. Good solution sir :waytogo:

    While thinking about it, and searching some I ran across this http://derale.com/products/transmis...male-x-3-8-barb-90-degree-barb-fitting-detail not sure if it would be any real benefit but figure if one is replacing the pan anyway and has clearance for a slightly larger pan it wouldn't hurt anything.
     
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  12. 77 K20

    77 K20 Full Access Member

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    Some good info here...

    I bought a trans-dapt slam guard transmission pan years ago because it has a drain plug on it. That and it has a built in 3/16 skid plate attached to it. (TH400 shown... not my transmission)

    [​IMG]
     
  13. Camar068

    Camar068 Supporting Member Supporting Member

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    Thanks...just ordered one.
     

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