RE5R05A Planetary 2003-2008

If your Nissan or Infiniti 5-speed automatic from the 2003 to 2008 model years has started to howl at highway speed, dropped a gear, or stopped moving altogether after metal showed up in the pan, the planetary gear train belongs on your suspect list. This is a used, original-equipment RE5R05A planetary carrier assembly listed for 2003-2008 units. Those years cover the first wave of RE5R05A cars and the rear-drive trucks and SUVs that were added after that, so read the fitment section before ordering. It ships from the USA with a 1-year warranty and it sells for $74.99, well under the cost of a new carrier.

What the planetary carrier does in a 2003-2008 RE5R05A

Inside the RE5R05A, three simple planetary gearsets sit one behind the other: front, middle and rear. A carrier is the cage that holds a set of pinion gears on steel pins and needle bearings. The pinions mesh with a sun gear in the center and a ring gear around the outside. Depending on which clutches and brakes are applied, the carrier is either driven, held still or allowed to turn freely, and that combination produces each of the five forward ratios and reverse. The gearsets are linked, so the rear carrier and the center ring gear work as one path to the output. In a documented FenderBender case, a rebuilt RE5R05A would not move because all 16 small tabs that index the center ring gear into the rear carrier had sheared off. The clutches were fine, but the gear train had come apart at that joint.

Symptoms of a worn or broken carrier

• A whine or hum that follows road speed rather than engine speed, and changes pitch when the transmission shifts
• One gear missing or slipping while the others engage normally
• No forward or reverse movement even with a full, clean fluid level
• Fine steel or bronze particles on the pan magnet from worn pinion pins, needle bearings or thrust washers
• A clunk or bind when the vehicle starts moving, caused by a pinion that has seized on its pin
• On a 2005-2008 truck or SUV, a carrier failure that follows radiator cooler contamination. Coolant in the fluid attacks bearings and bushings as well as friction material.

How to confirm it before you buy

A worn planetary is usually the last thing found, so rule out the common RE5R05A faults first. Check the fluid level hot, look for milky or pink fluid that points to a cooler leak, and pull codes. Valve body and solenoid problems cause harsh or missed shifts that can feel like a broken gear. Our RE5R05A service guide for Pathfinder, Armada and QX56 covers the fluid and pressure checks. Once the unit is apart, spin each pinion and feel for roughness or binding, rock the pinions to feel for pin wear, and check for blue heat marks around the pins. Then inspect every outer tab and inner spline where the carrier meets a ring gear, drum or hub. A cracked tab or a twisted spline means replace the part rather than reuse it.

Fitment

This carrier is listed for RE5R05A transmissions from 2003 through 2008. That range spans early cars such as the 350Z and G35 and the truck and SUV applications that followed. Nissan changed internal parts more than once in that period. Sonnax notes, for example, a solenoid resistance change in August 2005 on Infiniti units. Do not assume any 2003-2008 carrier swaps in blind. Lay this assembly next to the one you removed and match the pinion count, outer tab pattern, spline count and hub height, and confirm it is the same front, middle or rear position. The photos show the exact part you will receive. If you are not sure, send us your year and VIN and we will check it before it ships. For other parts for this unit, browse the RE5R05A parts collection. If your unit is a 2003 car transmission, also look at the 2003-only RE5R05A planetary.

Install notes

• Clean the assembly in solvent, blow it dry, and check pinion end play and thrust washer condition before it goes in. It is a used part, so inspect it as you would your own.
• Fit new thrust bearings and washers on both sides of the carrier and replace any bushing that shows copper or scoring.
• Check the drums that drive this gear train while the case is empty. A cracked or worn RE5R05A input drum for 2003-2008 leaks apply pressure and can look like a gear problem.
• If the old carrier made metal, replace the clutches, steels and seals too. The RE5R05A master rebuild kit for the 4.0L Nissan covers the later truck and SUV units.
• Install a new filter and pan gasket, and flush or replace the cooler and lines so leftover debris does not return to the new bearings.
• Fill with the Nissan ATF your owner's manual specifies. Later Frontier manuals list Matic S, with Matic J as the approved alternative. Set the level at operating temperature.

Does this carrier fit every 2003-2008 RE5R05A?

No single internal part should be assumed to fit every unit in a six-year span. It is listed for 2003-2008 RE5R05A transmissions, but compare the pinion count, tabs, splines and hub height with your old carrier, or send your year and VIN so we can confirm it first.

How do I know the planetary is the problem and not the valve body?

Valve body and solenoid faults usually set codes and cause harsh, late or missing shifts. A planetary problem causes a speed-related whine, metal in the pan, or a loss of drive that stays the same no matter how the unit is commanded. The carrier is confirmed on the bench by spinning the pinions and checking the tabs and splines.

Can a failed radiator cooler damage the planetary?

Yes. Coolant mixed into the ATF breaks down bearings, bushings and clutch material. If your truck or SUV had a cooler failure, replace the cooler and flush the system or the new carrier will be exposed to the same contamination.

What else should I replace with the carrier?

At minimum, the thrust bearings and washers on each side of the carrier and any worn bushings. If the old unit made metal, rebuild the clutch packs, install a new filter, and flush or replace the cooler.

What fluid does this transmission take?

Use the Nissan ATF listed in your owner's manual. Later Frontier manuals call for Matic S, with Matic J as the approved alternative. Check the level hot.

Is this part new?

It is a used original-equipment assembly, which keeps the cost down. Inspect it before installation, as you would any reused hard part. It is covered by a 1-year warranty.

• Nissan/Infiniti RE5R05A Transmission Service Guide: Pathfinder, Armada, QX56