Trans Cooler With Fan



Adding an aftermarket transmission cooler to your hot rod, car or truck is always a good idea. Here are some tips:

Any fan is useless at around 35-40 mph or faster. At that point, the airflow across the cooler would be restricted some by the fan. So if you're on the highway a lot, a bigger cooler would be your solution, not a fan. Fluid Cooler, Dual Pass Transmission, Includes Fan, 11.50 in. Overall Height, 12.50 in. Overall Width, 650 cfm, Kit. Part Number: SDM-PCE187-1001 Not Yet Reviewed. B&M's all-aluminum SuperCooler Automatic Transmission Coolers are designed with stamped plates that are sandwiched together to create a very efficient oil cooling device. These coolers not only maximize cooling through more efficient heat dissipation, but they are also stronger to. Rigid Race Fans. Standard Rotation Aluminum Blade; Standard Rotation Steel Blade; Reverse Rotation Steel Blade; Fan Clutch Fans. Standard Rotation; Reverse Rotation; Fan Spacers; Fluid Coolers. Remote Mount; Series 10000 Stacked Plate; Series 8000 Plate & Fin; Series 7000 Tube & Fin; Direct Fit; Engine Oil Cooler Installation Kits.

Always mount the cooler in a place that has good air flow

  • If you are mounting it in front of the radiator, always make sure the fin’s in the cooler are parallel with the fin’s in the radiator. This prevents restricting air flow to the radiator.

If you place the cooler in and area with little air flow, a fan is a must

When installing coolers, make sure lines are clear of anything that can rub them

Always use line that is approved for transmission/hydraulic fluid

  • Fuel line will not work and will break down in transmission fluid.

Bypassing the radiator is the way we prefer a cooler be set up. The transmission will generally run cooler this way

  • Additionally, this may take some of the load off the radiators job of cooling the engine.

When hooking up multiple coolers several things should be noted

  • The cooler itself is a restriction of flow and this restriction while not a problem for the cooling or lube to the transmission can cause excessive pressure inside the converter. This can force the converter against the flex plate more so than normal and cause wear to the engine thrust bearing. A stopped up or severely restricted cooler or cooler lines can do the same.
  • When installing more than one cooler, its advised to put them in parallel with each other, This means one line from the transmission is split with a Y and one line run to each cooler then out of each and into a Y back to a single line running to the transmission. This will assure adequate cooling while reducing the wear to the engine thrust bearing.
  • Always use line that’s at least as large as the inlets in the cooler, Avoid extreme twist or turns in them particularly with rubber lines.

Type and brands of coolers

  • We really have no preference here as far as brand. From our experience, an expensive brand name unit or a generic one seem to do the same job.
  • We have found the stacked plate (flat tube) types tend to be more efficient in the same dimensional sizes with a greater temperature drop.

Always be sure that the metal lines coming from the transmission under car do not contact the headers or exhaust

  • This is not specifically about a cooler but about cooling. If the cooler lines were in contact with the headers, it would super heat the fluid when the headers get hot. Make sure there is no contact so you won’t have a problem.
  • Always keep transmission cooler lines factory or otherwise as far away from the exhaust as possible.

Transmission temperatures – This question gets asked a lot. What’s TOO HOT?

  • Well, ideally you want your average temperature to stay under 190 degrees. However, we would not get too concerned until the temperature gets to or over 230 degrees.
  • Heat can damage a transmission by breaking down the fluid and causing rubber seals to harden and break.

Never attempt to remove fluid from your transmission by starting the engine

Never attempt to flush by catching fluid in a pan while adding fluid in the dipstick hole

  • When this is done, no lube is being sent to the gears and bushings. They can go dry and melt down very quickly, destroying or significantly shortening the life of your transmission.

It is advisable to fully and properly flush a cooler, especially when a converter failure is involved

  • A transmission internal failure is unlikely to put debris in the cooler, because all fluid coming from the transmission must travel through the trans filter.
  • Its always a good idea to power flush a cooler or replace it after a failure. It is particularly important in the type of failure. Anything that’s in your cooler or lines will end up in your valve body, bushings and gears.
  • A cooler cannot be properly cleaned simply by blowing air through it. A can of cooler flush, which most shops have, followed by being blown out with air is the correct way to do it.

When installing rubber cooler lines to metal lines always put a small flair at the end of the metal line

  • Not too big because you will tear the line on the inside during install. Then place a clamp just ahead of the flair.
  • Roughening up the outer surface of the metal line with coarse sand paper in the area where the clamp will ride will help assure a good seal and reduce the possibility of blow off.
  • Never over tighten clamps to the point of the rubber oozing through or being cut this will cause a failure too.

The best place for temperature sending units is in the pan

  • This is because it will give the best average temperature which is what’s important.
  • Using the pressure port is OK, however, you will show temps 10 to 20 degrees higher than in the pan.
  • We do not suggest placing temp senders in either the inlet or outlet from the cooler. This is because it will increase cooler restriction and increase the odds of a leak.

Diagram: Best Transmission Cooler Placement

Also of Interest:

Transmission cooler with electric fan

It’s no secret that heat kills automatic transmissions.

This is especially true in big-power, street-strip machines that combine lots of horsepower with a small torque converter and steep rear axle ratio. Engine rpm is up across the board, and the automatic transmission builds heat. This is also true for trucks that haul heavy loads or tow trailers battling tough conditions such as long grades, high altitudes, or desert heat. In any case, loads coupled with stop-and-go traffic increase the heat level in an automatic transmission.

How Hot is Too Hot?

The ideal operating temperature for automatic transmission fluid is somewhere between 175 and 225 degrees F. Here’s what can happen above this range:

  • At approximately 240 degrees F, important additives begin to cook in the automatic transmission fluid (ATF). The result is the formation of varnish inside the transmission.
  • At approximately 260 degrees F, internal transmission seals, which are often manufactured from a polyacrylate material, begin to harden. The end results are internal and external leaks as the the seals lose their elasticity.
  • At approximately 295 degrees F, transmission clutch plates begin to slip because the oil is breaking down further.
  • At approximately 315 degrees F, seals and clutches effectively burn out. Carbon forms in the oil and for all intents and purposes, the transmission is now junk. Often, a transmission will die within a few thousand miles (or sooner) if subjected to 300-plus degree heat.

The built-in coolers that reside in the bottom of the radiator are marginal at best. A typical “in-the-rad” cooler will reduce the heat of the ATF but it’s also influenced by the engine coolant temperature. And at the same time, it too can influence the engine coolant temperature.

How can that happen?

If the vehicle in question has a thermostat that opens at 195 degrees F, once warmed to operating temperature, the transmission cooler will have a tough time reducing the heat of the ATF below 195 degrees F. At the same time, if the transmission is overworked, it might raise the operating temperature of the ATF to 250 degrees F or more. This heat can be transferred to the engine coolant resulting in a potential boil over.

So what’s the answer?

You can add an external cooler. But before you rush out and buy the first cooler available, here’s an example to ponder:

Decades ago, we built an L88 powered 1969 Camaro complete with a turbo 400, a 12-bolt filled with 4.88:1 gears and an 8-inch torque converter. It was a street-driven car, but even with a big, four-core rad, the combination was always ready to melt the transmission fluid. In a conversation with Bob Fouts at Earl’s Performance, we garnered this critical kernel of information: It is virtually impossible to overcool an automatic transmission, especially one in a high performance application. Naturally, this might not apply to vehicles operating near the Arctic Circle, but in the rest of the world, it basically holds true.

Types of Coolers

Typically, there are two types of cooler styles available: “tube-and-fin” and the “stacked plate” cooler. A conventional tube-and-fin cooler is the most common type you’ll find. Generally speaking, this cooler configuration consists of fins that are placed over aluminum tubes, which are laid out in “S” patterns. The idea is to have air flow over the fins, which in turn creates a heat sink effect. This effect draws heat from the ATF. Tube-and-fin coolers are inexpensive and easy-to-build.

The other type of cooler that is available is the “stacked plate” design. This cooler is laid out in much the same manner as the radiator in your car. Rather than using a tube to carry the ATF inside the cooler, the fins actually form the passage for the fluid to pass through. This is almost identical to the process Detroit uses to build modern radiators. This type of cooler configuration is much more efficient than the tube-and-fin style. And if you search the Summit Racing website, you’ll see all sorts of good options, including top-of-the line versions from Earl’s Performance.

The stacked plate, or “modular” cooler, has been in use since prior to WWII. During the early 1930s, it was first developed for use with the Rolls Royce Merlin engine that powered the Spitfires and Hurricanes in the Battle of Britain. It was ideal because of its dense air fins and “turbulator plates” which provide maximum liquid side (internal) and airside (external) surface area. The collector or end tanks ensure minimum flow restriction, while the fully brazed construction results in the most efficient possible thermal transfer between liquid and air. This old Rolls Royce Merlin design is the most thermally efficient liquid-to-air heat exchanger format available.

Now, you’re probably saying: “there’s a big difference between the conditions seen in an aircraft and those experienced by my street driven car.” That’s true, but these old war birds were subsonic and piston powered. In today’s terms, those old aircraft were dead slow, and because of that, heat exchanger technology has more in common with today’s trucks and cars than you might think. Plus, a heat exchanger or cooler doesn’t know if it’s cooling engine oil, hydraulic fluid, or ATF. When this basic, modular design is utilized, and the oil flow and air speed of the vehicle is taken into consideration, then the optimum heat exchanger can be produced.

Stacked Plate vs. Tube-and-Fin Coolers

How effective is the stacked plate, modular design in comparison to a more common tube-and-fin arrangement? Typically, a modular cooler (such as the Earl’s coolers shown in the photos below) will reject as much as three times the heat for a given area than a tube-and-fin cooler. The modular configuration cooler will also have less than half of the pressure drop found in a tube-and-fin cooler.

Copper-Bass vs. Aluminum Coolers

When it comes to heat exchanger construction, what’s best: copper and brass or aluminum? In most cases, the aluminum exchangers are nearly as thermally efficient as the copper and brass versions, but significantly lighter. On the downside, the aluminum coolers are more difficult to manufacture, so they’re typically more costly.

Another thing to consider is the paint. The common black paint that is preferred by most local radiator shops can act as thermal barrier instead of promoting the transfer of heat. A proper aluminum heat exchanger will either be anodized, or it will have a very thin coat of baked, heat exchanger paint (typically grey, silver, or black in color).

Aeroflow trans cooler with fan

Fluid Cooler Mounting Tips

According to Earl’s Performance Products, the cooler must be mounted in a stream of moving air at ambient temperature to operate efficiently. It is not a good idea to mount the oil cooler behind the radiator where it will receive only heated air. It is not enough to lead air to the cooler; the heated air must have somewhere to go after it passes through the core. Air naturally flows from a region of relatively high pressure to a region of relatively low pressure, so you should mount your cooler in the airstream ahead of the vehicle radiator. That way, it will always be subject to high pressure at the face, and the engine fan will always provide a region of low pressure behind the cooler.

Trans Cooler Kit

You also need to consider the location of the inlet and outlet ports. Coolers should never be mounted so that both the inlet and outlet ports are on the bottom. The best method is to have the ports on the top. If this isn’t possible, the next best scenario has the cooler mounted on the side so that the ports are arranged horizontally.

There are a number of ways to mount the cooler; however, Earl’s offers a slick system for their coolers. This aluminum bracket is designed to hold the cooler securely without damage from vibration. Included is a pair of brackets (with integral rubber cushions) and e-coated aircraft quality hardware with rubber insulators spacers. Earl’s offers this bracket system for all of their Temp-A-Cure cooler models.

Port configuration is usually a matter of preference. The Earl’s coolers incorporate -10 AN O-ring boss ports. From here, you simply select the AN adapter that suits your needs. It’s no secret AN fittings are less prone to leakage and obviously much more secure than pipe thread examples. A -6 AN arrangement is most common for an automatic transmission.

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Trans Cooler With Fan

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Selecting a Cooler Size

For high performance street cars or trucks that are subjected to heavy loads or towing, bigger is always better. As we’ve already mentioned, it’s impossible to overcool an automatic transmission.

B&m Trans Cooler With Fan

The nature of the Earl’s Temp-A-Cure cooler (shown in the slideshow) allows it to be manufactured in countless different sizes. In fact, Earl’s offers a wide array of coolers to suit almost any application. The narrow 8¼-inch wide coolers are available in heights ranging from 2 to 18½ inches. Along with the narrow coolers, you can purchase wide body coolers. The “extra wide” coolers from Earl’s have a width of 15¼ inches and heights range from 2 to 18½-inches. Finally, Earl’s manufactures curved coolers that have a width of 11.562-inches and a height from 3.05 inches up to 4.919 inches. Basically, any cooler with a face height up to 18½ inches can be created.

In the end, money that’s spent on a proper cooler is like money in the bank. Not only will your transmission live longer, it will also be more efficient.