Transfer Case Bearing and Seal Kit, 263XHD, Duramax | 2001-2007

The Merchant Automotive Bearing and Seal Kit for the NP263XHD transfer case includes the bearings and seals throughout the transfer case, plus the low range shift fork pads and the planetary thrust washers. It is the kit to use when you want to completely refresh your transfer case, especially after a low fluid situation such as a pump rub leak or seal leak. It fits the electronic shift NP263XHD in 2001-2007 Chevy Silverado and GMC Sierra 2500HD and 3500HD trucks with the 6.6L Duramax diesel (LB7, LLY and LBZ).

Features

• Bearings and seals for a complete NP263XHD refresh
• Includes the range hub shift fork pads and planetary thrust washers
• Includes the transfer case to transmission adapter gasket
• Every part in the kit is also sold separately

What's Included

• (1) A23 speed sensor seal (10238)
• (1) A13 rear output seal (22049)
• (1) Transfer case to transmission adapter gasket (331304A)
• (1) Snap ring hole grommet (88958815)
• (1) B25 rear output shaft bearing (B41-6)
• (1) A7 front output seal (411081A)
• (1) A9 front input seal (411070A)
• (1) B18 front output shaft needle bearing (303211A)
• (1) B22 front input/output shaft bearing (325287)
• (1) A17 range hub shift fork pad kit (pair) (37284-2)
• (2) B12 planetary thrust washers (411215)
• (1) A33 detent lever selector shaft bearing (411279)
• (1) B11 input gear bearing (DB73167)
• (1) B8 front input bearing, XHD (351240)
• (1) Selector shaft sensor and detent plug O-ring (401330)
• (1) B30 pickup tube O-ring, 49 spline pump (12478088)

What is a Transfer Case "Pump Rub" Failure?

GM transfer cases used from 1998 through early 2007 have a gear pump inside the case that is driven off the mainshaft. The pump sends oil to the planetary and the drive sprocket sleeve. Because the pump is driven by the shaft, the pump housing must "float" in the rear housing. Tabs around the pump housing fit into spots in the rear housing to locate it and keep it from spinning with the mainshaft. Over time, the pump tabs can wear on the rear housing. GM installed a spring steel clip in the housing to prevent wear, but the clip can break.

The aluminum pump housing is harder than the magnesium rear housing, so it can wear a hole in the rear housing and cause a small leak. The leak is often high enough on the case that it does not drip when the truck is parked, but it leaks while driving. Because the transfer case has no low fluid indicator, pump rub is often not found until the case has been damaged from running low on fluid. A Merchant Automotive Transfer Case Pump Upgrade kit is designed to prevent pump rub. Click here to view the Merchant Automotive Transfer Case Pump Upgrade kits.

The Merchant Automotive Transfer Case Pump Upgrade kits come with a limited lifetime warranty against pump rub. If you already have a hole in your case, we recommend installing a new rear housing for a complete repair.

Before You Order

• 263XHD only: this kit is for the electronic shift NP263XHD (push button or knob on the dash). For the manual shift NP261XHD, see the 261XHD Bearing and Seal Kit.
• RTV not included: Click here to view the RTV silicone needed to seal the transfer case halves on reassembly.

Installation Tips

• Make sure the rear output bearing snap ring is fully seated in the rear housing and in the locating groove of the bearing.
• Click here to view the Merchant Automotive Rear Housing Supports.

Related Parts

• Transfer Case Pump Upgrade Kit with Magnetic Drain Plugs and Fluid
• Transfer Case Snap Ring Kit, 263XHD
• Sil-Bond RTV 4500 Silicone Sealant, 2.8 oz

Frequently Asked Questions

Is the transfer case behind the Allison 1000 or ZF6 in my 2001 through early 2007 truck an NP261XHD or NP263XHD?
The easiest way to tell is the shift selector. Trucks with a floor mounted shift lever use the NP261XHD. Trucks with electronic shift (a push button or knob on the dash) use the NP263XHD.

How tight do I tighten the transfer case mounting nuts at the transmission output adapter?
The factory recommended torque specification is 37 ft-lbs for the NP261XHD and NP263XHD.

How tight do I tighten the transfer case assembly bolts at the transmission output adapter?
The factory recommended torque specification is 27 ft-lbs for the NP261XHD and NP263XHD.

I hear a grinding noise at low speed after reassembling my transfer case. What could that be?
A low speed grinding noise is most commonly caused by the rear output bearing snap ring not being fully seated, which lets the bearing move out of alignment. Verify that the snap ring is fully engaged and seated in the rear housing and the locating groove in the bearing.

What would cause a speed sensor correlation code after a rebuild?
A speed sensor correlation code often comes with a low speed grinding noise and is frequently caused by the same rear output bearing snap ring not being fully seated. Verify that the snap ring is fully engaged and properly seated.

For warranty information, see our Warranty Policy.