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  • Transfer Case Pump Upgrade and Repair Kit | Gas

Transfer Case Pump Upgrade and Repair Kit | Gas

7 Reviews
SKU: 10770


This kit is designed to repair and upgrade either a 149, 246, 261HD, or 263HD transfer case when "pump rub" has worn a hole in your housing.


To open instructions click here.

What is "pump rub"

The GM transfer cases use a gear pump inside the case that is driven off the mainshaft. The pump forces oil to the planetary as well as the drive sprocket sleeve. Because the pump is driven by the shaft, the housing of the pump must 'float' in the rear housing. There are 5 tabs around the housing that fit into spots in the rear housing to position the pump. Over time, the pump can start to wear on the rear housing. GM installed a spring steel clip in the housing intended to prevent wear, but the clip can break and be rendered useless.

Being that the pump housing is aluminum and is a harder material then the magnesium rear housing, it can wear a hole in the rear housing and cause a very small leak. This leak is high enough in the case that it typically will not leak when vehicle is not moving and therefor not leaving any drops on the ground. Typically the condition is not found until there is transfer case damage from running the case out of fluid. 

Avoid costly repairs to your transfer case by preventing this condition. 

With installation of this kit, you will have a LIMITED LIFETIME WARRANTY against pump rub. If your case ever wears a hole in the new rear housing with the upgrade installed. We will buy you a new transfer case.

If you already have a hole in your case, its recommended to install a new rear housing for a proper repair. Lifetime warranty will only apply to installations with a new rear housing.


What do I do with the OEM anti rattle clip when installing this upgrade?

You can discard the factory clip during installation of this kit. It's been designed to work with the clip removed. 

What other parts will I need to install this upgrade kit?

We tried to make the kit all inclusive for a basic installation. This is taking into consideration of course that its being installed as preventative measures. If it's being installed as part of a repair or after pump rub has occurred, there is no real way to know the extent of the damage inside the case until it is torn down. Most times, as long as the case has not run out of fluid, it can usually be repaired with a new rear housing and seal and prevented from ever happening again using the upgrade kit. Regardless of the reason for installing this upgrade, you will need to refill the transfer case with oil. We recommend our Performance Transfer Case Oil for use in ALL transfer cases.


GM Transfer Cases
149, 246, 261HD, 263HD

2001, 2002, 2003, 2004, 2005, 2006, 2007

Ratings & Reviews

7 Reviews

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  • 1 star
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Np 246 Kit

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Awesome kit if you are looking for an all in one set up. Videos spell it out step by step on how to install the pump saver. Pay very close attention when setting the last lock ring. Mine did not go in the groove all the way and made a whining sound. Had to remove the case again to fix the lock ring. Good as new now. Prompt shipping and great service.

NP246-G Transfer case fix

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This kit is the best fix for the NewProcess/NewVenture xfer cases that develop the pin hole leak. What would make this the inch PERFECTinch fix is new torx screws with the proper torque specification, infact all the torque specs since you have to hunt for them across the internet and not all are the same. Other than that, this kit will get the job done.

combo kit

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installed housing kit worked great thanks tom

Happy customer

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Great job of getting the parts to me that I ordered. Timely and everything was in the box. Appreciate the great service. i will order again in the future.

Great Product

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Shipped promptly worked just as advertised. Only issue is the oil has to All be pumped in to transfer case. Any spillage leaves the case that much low on oil.

Thanks Guys!

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My 2005 Silverado got a hole in the transfer case housing at about 110,000 miles. The guys at merchant automotive were super helpful before and after my purchase. Between them and a lot of YouTube videos, I was able to replace the oil pump housing and case half, and get everything put back together correctly. It had a squealing sound on my first test drive, the guys at Merchant automotive helped me diagnose it and had me go back and adjust a snap ring I hadn't installed correctly fixing the problem. Now everything works great! I highly recommend you take your business to Merchant Automotive.

Transfer case upgrade

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I was very pleased on how fast the shipping was. The upgrade kit works perfect very well made! I also ordered the rear transfer case housing because my oil pump wore a hole in mine. I had it all takin apart and out of my pickup and put back in all in under 5 hours by myself. I am very satisfied with how it all went together! Thanks A lot!!!!