Here is the best upgrade you can make to your GM transfer case(model 136, 146, 246, 261, 261HD, 263HD, 263XHD, 261XHD). Prevent the ever increasing problem of
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 render 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. Full installation instructions are available right here on this site. Look under the Tech Information link on the home page for step by step directions. 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. Included in the kit:
Merchant Automotive billet transfer case pump housing
Transfer case adapter gasket at trans
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.
Check out our transfer case upgrade as featured on Truck U TV on Speed Channel
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. Its 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 its being installed as part of a repair or after pump rub has occured, 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.
Replace your stock drain plug with Magnetic Drain Plugs to catch small debris and help extend fluid life. Kit contains a Magnetic Drain plug and a new fill plug made out of a high strength corrosion resistant 304 Stainless Steel.
Promotes transfer case performance
Increases shifting performance
Dramatically reduces wear
Increases component efficiency
Blended specifically for use in GM transfer cases
May be used in GM, Ford and Chrysler transfer cases
For use in diesel or gas transfercase
Cost effective upgrade for Auto Track II
Performs in manual or electric shift applications
Reduces irritating drive shaft clunk
Increases drive line performance by reducing clutch chatter
Drastically reduces wear on internal components & seals
2 Quarts (64 fluid oz.) One Transfer Case will use 64 fluid oz.
Pump upgrade, April 7, 2018 By Anonymous (Medina, OH)(Verified)
Really nice product, quick shipping and quick help finding the right part.
Potential problems solved!!!!, March 27, 2018 By Anonymous (KIRKSVILLE, MO)(Verified)
We got lucky as our 2006 LBZ only has 75,000 on it, and the spring clip was it place BUT, it had already started to wear a small spot. We installed the kit and also installed the transfer case brace. Instruction were clear and easy to follow. We also put in new seals, one was a real turd, but we replaced them all, which took a little longer that just the kit. The brace only took a few minutes when putting case back in. The mechanic that gave me a hand is a transmission 'guru' and was impressed with both the hub kit and the brace. He thought they were excellent preventative measures and has seen several cases destroyed by the problems these two items prevent. Am very satisfied with these two products. The rear output bearing was in great shape so we did not need to use it,
Best Pump rub kit out, March 20, 2018 By Josh (Lacey, WA)
Got this quality kit 7 years ago. I've installed several since. This by far is the best kit on the market. Still in my truck to this day.
Quality Product,, March 6, 2018 By Anonymous (Bradenton, FL)(Verified)
Quality Product, Product exceeds expectations. Simple to install with basic mechanical experience.
Transfer case pump rub kit, February 25, 2018 By Anonymous (Edinburgh, IN)(Verified)
Excellent product !!!!
Perfect!!, February 18, 2018 By Anonymous (GLENDORA, CA)(Verified)
You earned a customer for life! Kit was complete and as easy to install as they said it would be! So nice to find a company that delivers on its claims!
I am an OG pump housing buyer, January 7, 2018 By John Tollison (DeFuniak Springs, FL)
This kit is nothing but fantastic, I bought my kit back in 2006 when they were just coming out, and the price was 275 bucks! Still money well spent. Well here I am 12 years later and still running the same case half with my epoxy patch and all is well! If you have not bought this kit, I can show you pictures of what I have encountered inside transfer cases.... do the pump housing, you will not regret it!
Great product all around, October 27, 2017 By Anonymous (Gray, ME)(Verified)
Just did my 263 @ 150k. Thankfully it was still in great shape. Great product, and instructions. Very easy. Only thing i'd add to the instructions is to clean the magnet below the oil pickup before reassembly.
Complete kit, October 19, 2017 By Daniel (Conway, AR)(Verified)
Great product and easy to install. I love that it comes with everything you need to complete the job.
Rub Kit, September 20, 2017 By James (BALSAM LAKE, WI)(Verified)
Product is everything as advertised,came in a timely fashion, only thing I would add to the directions is to lube the pump plates before you reinstall with grease or transmission fluid.
pump rub, September 7, 2017 By Anonymous (PAYSON, AZ)(Verified)
Quality product and easy to follow instructions.
Transfer Case Pump Upgrade, August 22, 2017 By Anonymous (Littleton, CO)(Verified)
This is a great product design to save your case if you catch it in time., I did...98k miles The online video walks you right thru it step by step great job Merchant Automotive!!!!!
2006 K3500, August 22, 2017 By Anonymous (Shoreview, MN)(Verified)
Fits perfect. Easy install. 263XHDGM
Pump upgrade, August 22, 2017 By Anonymous (FAYETTEVILLE, NC)(Verified)
Great part easy to install. Easy on the wallet
Great product, August 21, 2017 By Nick (Byron, IL)(Verified)
Heard from a friend about this fix. Easy do it yourself update. Instructions are step by step, can't mess it up. Glad I did this before I had any problems with my transfer case. Also great that Merchant Automotive does offer bearing and seal kits.
Great Product, August 3, 2017 By Anonymous (Welland)(Verified)
The parts and the video on how to install them were great i have put about 4000 km on since i installed the new pump. the machining and fit of all the parts were great thanks for all the help and the follow up to make sure every thing went well thanks again and i have recommended you to a lot of friends who have a lot of duramax trucks and chevy gas trucks thanks again
Awesome! Thank you Merchant, July 26, 2017 By John (New York, NY)
I do not understand why GM did not do a recall on this issue. Thank you so much for making this product. I did not want a hole in my T-Case!