48RE Clutch Module 1989-2007

If you tow with a 5.9L Cummins Ram and watch the transmission temperature climb on every long grade, or you are tired of a stamped pan that weeps at the gasket and has no drain plug, a deep aluminum pan is one of the simplest upgrades you can make. This listing is the Mag-Hytec 727-D deep transmission pan, a cast-aluminum replacement pan for the Chrysler RH and RE family behind the Cummins: the 47RE and 48RE, plus the 36RH, 37RH, 46RH, 47RH and 46RE that share the same pan pattern. It is not a clutch pack. It is the pan that holds and cools the fluid those clutches live in.

What is in the box

• The 727-D pan, cast in A356-T6 aluminum with machined cooling fins and a black textured powder coat, about 3 7/8 inches tall overall
• A fiber pan gasket, which Mag-Hytec specifies over cork or rubber for an aluminum pan on an aluminum case
• Fourteen 5/16-18 Allen head cap screws and stainless washers
• A magnetic drain plug sealed with an O-ring, already installed
• A 1/8 NPT port with a stainless plug for an optional temperature sender
• A filter spacer block and the three Allen keys needed to install and service the pan

A transmission filter is not included, so order one with the pan.

What a deep pan does in a 47RE or 48RE

The pan is the sump for the whole hydraulic system. The pump draws from it through the filter, and everything that comes back from the cooler and the lube circuit drains into it. A deeper cast pan adds fluid volume, puts more metal and fin area in the airflow under the truck, and is stiff enough that the flange will not bow when the bolts are torqued. Mag-Hytec rates the 727-D at 6.5 quarts in the pan: about 1.5 quarts more than a stock pan on trucks built before 1998, and about half a quart more than the factory pan used from 1999 on. The spacer block lowers the filter so its pickup still sits near the bottom of the deeper sump. The magnet in the drain plug catches the fine steel that every automatic sheds, so you see it at each service instead of it circulating through the valve body.

Symptoms that point to a pan upgrade

• Fluid running hot when towing or climbing, with dark or burnt-smelling ATF at service time
• A leaking pan gasket on a stamped pan that has been dented or over-torqued
• No drain plug, so every service means dropping a full pan of hot fluid
• Repeated overdrive or direct clutch wear on a working truck, where heat is often part of the cause

Heat is the enemy here. GEARS Magazine puts the ideal maximum fluid temperature for these heavy-duty Chrysler units around 200 degrees F and notes that transmission life roughly halves for every 20 degrees above it. Our 48RE Cummins transmission problems guide covers how that heat shows up as clutch and converter failures.

How to confirm what you need first

A pan adds capacity, but it will not fix a restricted cooler or a worn pump. Before you buy, check that the cooler is flowing (GEARS suggests a minimum of about one gallon per minute) and look at what is in the old pan. Fine gray paste on the magnet is normal wear; larger metal chips or a lot of friction material means the transmission needs inspection before you button it back up. The 48RE pump failure guide walks through pressure and cooler flow checks, and the 3-4 clutch failure guide explains what burnt overdrive frictions in the pan mean.

Fitment

Listed for 1989-1993 Dodge Ram D250 and D350 trucks with the 5.9L Cummins and 1994-2007 Ram 2500 and 3500 trucks with the 5.9L Cummins and the 47RE or 48RE. It also fits the 36RH, 37RH, 46RH, 47RH and 46RE that use the same 14-bolt pan pattern. Mag-Hytec warns that factory options or aftermarket parts such as exhaust, crossmembers or skid plates can cause clearance problems, so look at the space under your pan before ordering. If you are not sure which transmission your truck has, send us the year and VIN. Other parts for these trucks are on our 48RE collection page.

Install notes

• Remove all but two old pan bolts starting at the rear, then let the pan tip and drain before pulling it. Scrape the old gasket or sealant off the case without gouging it, and file down any high spots so the flange is flat.
• Replace the filter while the pan is off. A 48RE governor solenoid, transducer and filter kit covers the filter and the governor pressure parts in one job.
• Lightly oil the drain plug O-ring, start all 14 cap screws by hand, then torque them to 12-16 ft-lb in a cross pattern. Mag-Hytec calls for waiting 10 minutes and repeating the torque until no bolt moves, since the fiber gasket settles.
• Snug the drain plug and the 1/8 plug by hand with the short side of the Allen key; do not overtighten. Install a temperature sender in the port now if you want one.
• Fill with Mopar ATF+4 to the full mark on the factory dipstick, checked hot in Neutral. For hard-towing trucks, adding cooler capacity with an oil cooler heat exchanger complements the deeper sump.

Is this a clutch module?

No. Despite the listing name, this item is the Mag-Hytec 727-D deep aluminum transmission pan for 47RE and 48RE Cummins Rams and the related RH and RE units. It replaces the factory pan; it contains no clutch plates.

Which trucks does it fit?

1989-1993 Ram D250 and D350 and 1994-2007 Ram 2500 and 3500 with the 5.9L Cummins and a 47RE or 48RE. It also fits the 36RH, 37RH, 46RH, 47RH and 46RE. Check clearance around exhaust and aftermarket parts, or send us your year and VIN.

How much extra fluid does it hold?

Mag-Hytec rates the pan at 6.5 quarts, roughly 1.5 quarts over a pre-1998 stock pan and about half a quart over the 1999 and later factory pan. Fill to the full mark on your factory dipstick with the fluid hot.

Does it come with a filter?

No. It includes the gasket, cap screws, washers, magnetic drain plug, a sender port plug, a filter spacer block and Allen keys. Buy a new filter to install at the same time.

What fluid and torque should I use?

Mopar ATF+4 for these trucks. Torque the 14 cap screws to 12-16 ft-lb in a cross pattern, wait 10 minutes and repeat until none move, then fill.

Can I add a temperature gauge?

Yes. The pan has a 1/8 NPT port with a stainless plug. Remove the plug and thread in a sender with anti-seize on the threads.

• 48RE Cummins Transmission Problems: Failure Points, Upgrades, and What Actually Breaks
• 48RE Pump Failure Symptoms and Replacement
• 48RE 3-4 Clutch Failure: Symptoms and Fix
• 48RE Ram 2500 Cummins Common Problems and Fixes