Whether you’re off-roading, towing/hauling or just pushing around big off-road tires, your transmission is hard at work. This is especially the case for automatic transmissions.

Late-model trucks have complex automatic transmissions that include gears, hydraulics, electronics and a computer. All these items have to work like clockwork in order for your transmission to maximize torque and power to the wheels.

An easy upgrade to help performance and prolong the transmission’s life can be done by simply adding a high-capacity oil pan (a.k.a. deep-sump) and high-quality Automatic Transmission Fluid (ATF).

We were able to get our hands on a BD Heavy-Duty Transmission Pan for the 48RE Dodge 4-speed automatic transmission.  This Heavy-Duty pan adds an extra quart of fluid capacity and protection. Made from 356-T6 cast aluminum, it boasts a very strong design and incorporates exterior fins on the bottom that allows heat to dissipate faster.  This helps keep your ATF at a good operating temperature, especially when climbing hills, towing or racing.

Also featured on the BD Heavy-Duty Transmission Pan is a Zero-leak Gold plug that allows for easy oil draining. No more having to remove 14 bolts and making a mess while lowering the factory pan. The BD pan also has a magnetic donut on the bottom that will catch any metal debris so they don’t continue to grind away at the internals of your transmission. Last but not least, it’s pre-tapped for a temperature-sending unit. We’ve been in dire need of this to finish up our Auto Meter Diesel Gauges.

For fluid, we contacted Lucas Oil and quickly got a stock of their Semi-Synthetic Transmission Oil, which is compatible with our 48RE. You’ll need about 15 quarts to completely change the ATF.

Since we were dropping the pan, it was a good time to swap out the transmission filter.It’s recommend by Dodge that the filter and fluid be changed every 30K miles. We picked up a genuine Mopar filter at the local dealer.

All set and ready to go.

INSTALLATION

You’ll need a few simple tools for the Job.

• Oil Drain/Recycle Pan
• Safety Glasses
• Can of Brake Cleaner
• Gasket Scraper
• 7/16 socket wrench with driver
• 1/4 Allen bit with 3/8 ratchet
• Allen socket
• Torx wrench set (for filter)
• Torque wrench

To make things simple, we recommend the use of an oil-recycling pan with a completely open top. The ones typically used for doing an engine oil change and recycling the oil won’t work. The oil from the transmission will come down fast once that pan comes off—which will lead to an overflow problem in your little black tub.  Get the big open lid one. Trust us.

Before you get too excited and start taking bolts off your pan, make sure you have all the necessary parts. Provided with the BD HD Transmission Pan should be:

1 – Temp Sensor Port Plug
1 – Magnetic Drain Plug
1 – Pan Gasket
14 – Trans Pan Bolt
14 – Tran Pan Washer

Make sure the truck is on level ground, in park and cool to work on. You don’t want to get burned by hot oil.

Start by placing the big drain pan below the transmission. Loosen all 14 bolts around the oil pan starting in the rear.

You’ll notice some oil starting to come out the sides. Eventually you will need to remove all the bolts to bring the factory pan down. This can be messy. Carefully bring it down and completely drain into the drain pan. Don’t worry, you won’t get 3 gallons of oil in your face. Most of it will remain in the torque converter and internal veins of the transmission. You’ll only get about 3-4 quarts from dropping the pan.

Next, remove the oil filter to allow the remaining oil to drain out.  Two torx bolts will need to be removed.

Using a lint-free rag, clean the perimeter of the gasket surface. If necessary, using a gasket scrapper clean off the surface.  You can use the brake parts cleaner to finish it off (only the perimeter, not the complete bottom of the transmission).

After the transmission stops draining, install the new filter with the torx bolt.

BD Power recommends applying a thin coat of ATF oil to the magnetic drain plug o-ring before putting it on. Tighten to 30lbs-in with a torque wrench. 

BD provides new Allen pan bolts. These aluminum bolts will need to be tightened in a criss-cross order to keep equal pressure around the pan and gasket. Final torque spec is 12 lb-in.

Last but not least was adding ATF fluid. We used the Lucas Semi-Synthetic Automatic Transmission Fluid for the job. This fluid is Chrysler ATF approved and designed to provide:

• Smooth Shifting
• Excellent heat resistance
• Recommended for both new and used vehicles
• Compatible with synthetic and conventional fluids

While we were at it, we also added Lucas Automatic Transmission Fluid Conditioner. Lucas claims it will:

• Improve Shifting
• Reduce noise and Shudder
• Compatible with all ATF fluids, conventional and synthetic
• Extend fluid life
• Will not void new car warranty

To get back to the fill mark on the dipstick it will only take about 5-6 quarts.  If you want to replace the full quantity of the transmission with new ATF, you will need to take it into a mechanic that can flush out the system with a machine. It will take about 15 quarts to completely replace the entire system with new ATF.

Another option is to run it with the 5-6 quarts you just added around the block to let the oil in the torque converter and oil cooler rotate through the system.  Then drain the oil from the pan and add another 5-6 quarts or until full. It’s not 100% replacement, but it’s as close as you can get in your own garage.

You’re done!

FINAL THOUGHTS

We are really impressed with the precision with which the BD Power Transmission Pan is made. It was an exact fit.

Having BD supply all the necessary hardware and gasket to complete the job makes it a true bolt-on application. The machined BD Power logo on the sides adds a nice touch to the rugged black enamel exterior.

We also really like the fins on the bottom. They look great, but most importantly serve a function, keeping the ATF fluid at a safe operating temperature. ATF is designed to operate at 175° F, and anything higher will degrade its lubrication properties quickly. This shortens the life of your transmission.

We really liked having the pre-tapped hole for the temperature-sending unit. Now we can accurately monitor our transmission oil temperature from the comfort of the driver seat using the Auto Meter gauges.

Lastly, the drain plug is a nice addition to the transmission. Now we can quickly change the ATF oil by only removing one plug and not the entire pan like we had to with the factory unit. 

The magnetic drain plug that comes with the BD also gives us reassurance that we are protecting our transmission from metallic particles getting back in the system once released from internal parts, such as the clutches and gears.

Our first few miles have been trouble free. We’ll be towing and hauling over 1,000 miles in the next few weeks. At that time we’ll come back with an update on how our addition did on and off-road. We’ll also report on how the oil held up and how our transmission reacted with these improvements.

Stay posted!

SOURCES
BD Diesel Power
http://www.dieselperformance.com/

Lucas Oil
http://www.lucasoil.com/

MOPAR
http://www.mopar.com/

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