I have a transfer case leak,

ken1mod · April 22, 2006

I would definitely do the jb weld thing, it's just epoxy with filler but I have had very good results for this type of thing. You might also consider a product called Marine Tex which is obviously used in the boating industry. Either will surprise you with the good results.

ken

ssmith · May 17, 2007

Well , that hole in the trasfer case is just about guarnteed sometime during the life of the truck. Some sooner than others. It's caused by the pump in the case wearing through from the inside out. There is a little clip that holds the pump from moving that breaks and lets the pump move back into the pocket and start wearing the case. I just replaced my case since I didn't catch the leak until it drained the case and destroyed itself from lack of lube. There is a GM Tech in MI that has developed a fix for this problem, if you catch it before it wrecks your case it's a lot cheaper than if you don't. I ended up spending about $1650.00 to replace my case with a modified one. New Venture who makes the transfer case doesn't seem too interested in making a simple modification to keep this from happening. I can't believe that no one here on this forum hasn't run into someone that this has happened to.

If you go to dieselplace.com and do a search for , pump rubbing hole in transfer case, you will find a lot of info about this all too common problem.

If all you do is JB weld it you will only delay the pump wearing through again, either there or in one of the other pockets that the pump rests in.

This problem seems to be all to common, I have just joined the pump rub club and want to know if there are any GM service bulletins on theis issue.

billo52 · May 17, 2007

See this thread http://www.gm-trucks.com/forums/index.php?showtopic=59813

You can just replace the rear half of the transfer case and the spring clip(sorry, no part numbers)

div4gold · June 5, 2007

See this thread http://www.gm-trucks.com/forums/index.php?showtopic=59813
You can just replace the rear half of the transfer case and the spring clip(sorry, no part numbers)

That's correct if you catch it before you lose your oil and completely destroy the transfer case. More destroyed cases than ones that were fixed before they are wrecked. Seems like GM would confornt this problem instead of just letting it continue. They must figure that the problem develops after warranty so what the heck.

div4gold · January 3, 2008

Subject: TSB – Transfer Case Housing Failure #03-06-04-054 (04/01/2007)

Models:2001-2007 Chevrolet Silverado

2001-2007 GMC Sierra

With Four Wheel Drive

This bulletin is being issued regarding problems

encountered with holes in the New Process Transfer cases used in

all light duty pick up trucks.

Several customers have been reporting holes developing in their transfer cases, particularly in high mileage vehicles.

The source of this hole is from the internal transfer case pump rubbing against the housing and wearing through the case wall.

ACTION:

If the vehicle is within the specified warranty period service technicians should thoroughly clean the exterior

surface of the transfer case around the hole. Apply a suitable amount of GM Adhesive, Part Number 142239JB (JB Weld) to ensure

the transfer case leak will stop until the truck is out of warranty. Refill with the appropriate oil.

If the vehicle is no longer within the warranty service period, deny any problem exists and blame the hole on:

1) Improper maintenance

2) Collision Damage

3) Off road incident

4) Road debris

Under no circumstance should you acknowledge the condition referred to as “Pump Rub”.

If questioned, deny that it exists, except possibly in vehicles meant for overseas sales.

GM Bulletin #03-06-04-054

For Internal Use Only

topdj · January 6, 2008

Subject: TSB – Transfer Case Housing Failure #03-06-04-054 (04/01/2007)
Models:2001-2007 Chevrolet Silverado

2001-2007 GMC Sierra

With Four Wheel Drive

This bulletin is being issued regarding problems

encountered with holes in the New Process Transfer cases used in

all light duty pick up trucks.

Several customers have been reporting holes developing in their transfer cases, particularly in high mileage vehicles.

The source of this hole is from the internal transfer case pump rubbing against the housing and wearing through the case wall.

ACTION:

If the vehicle is within the specified warranty period service technicians should thoroughly clean the exterior

surface of the transfer case around the hole. Apply a suitable amount of GM Adhesive, Part Number 142239JB (JB Weld) to ensure

the transfer case leak will stop until the truck is out of warranty. Refill with the appropriate oil.

If the vehicle is no longer within the warranty service period, deny any problem exists and blame the hole on:

1) Improper maintenance

2) Collision Damage

3) Off road incident

4) Road debris

Under no circumstance should you acknowledge the condition referred to as "Pump Rub".

If questioned, deny that it exists, except possibly in vehicles meant for overseas sales.

GM Bulletin #03-06-04-054

For Internal Use Only

I can't believe some of the comments in the bulletin WOW

the tranfercase on the NBS 07-08up is different

Metro12 · January 6, 2008

"deny that it exists"

OMFG!! You always figure they tell the techs this, just hard to believe they put it in writing!!

div4gold · January 6, 2008

"deny that it exists"

OMFG!! You always figure they tell the techs this, just hard to believe they put it in writing!!

Check the date of the TSB It probably isn't too far off though.

minibike132 · January 6, 2008

I have no idea where that doc came from it doesn't even look like gm body. I looked up the specific # included with that tsb the posted doc is a fake. Even if GM wanted us to deny something there is no way they would put it in writing for all to see.

Subject:SMU - Revised Fuel Injector Balance Test with Tech 2 (Automatic Transmission) #03-06-04-054 - (09/26/2003)

Models:2001-2004 Chevrolet Silverado

2003-2004 Chevrolet Kodiak

2001-2004 GMC Sierra

2003-2004 GMC TopKick

with 6.6L Diesel Engine (VIN 1 - RPO LB7)

This bulletin is being issued to revise the Fuel Injector Balance Test with Tech 2 (Automatic Transmission) in the Engine Controls sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.

The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.

Circuit Description

The Fuel Injector Balance Test is performed when a misfire, knock, excessive smoke, or rough running condition exists with no electrical diagnostic trouble codes (DTCs). During the Cylinder Power Balance portion of the test, the engine control module (ECM) turns OFF individual injectors while the engine is running and the scan tool displays engine RPM. The ECM adjusts for the drop in engine speed, so the power contribution of each cylinder must be felt by the technician. If a fuel injector is turned OFF and there is a different power contribution observed when compared to the other cylinders, that cylinder is identified with the complaint. If the customer complaint occurs during idle or during off-idle tip in acceleration, the balance rates are used to identify the cylinder with a fault related to the fuel injector or engine compression. If a fuel injector is turned OFF and the engine noise or smoke disappears, that cylinder has a fuel injector or engine compression condition.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

<LI value=4>The balance rate adjustments are utilized by the ECM only at idle. The balance rates are the fuel adjustments for each individual cylinder based on the variations in engine crankshaft speed. A positive value indicates that fuel is being added to each cylinder event, such as with poor engine compression or a fuel injector that is not flowing enough fuel. A negative value indicates fuel being removed from each cylinder event, such as a fuel injector that is flowing too much fuel. The balance rates will change depending on if the transmission is in Neutral or Drive.

<A name=TD05><LI value=5>This step determines if the ECM can control a stable fuel pressure. A high balance rate may be caused by a fuel injector or compression only if the ECM can control fuel pressure.

<A name=TD06>
The Cylinder Power Balance Test may be performed at any engine speed or load from idle to wide-open throttle. There is a 5 minute time limit for each test. The ECM and scan tool must both be powered down to reset the timer.

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check-Engine Controls

2

Are any DTCs set other than P0300, P0301-P0308?

--

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3

Does the customer concern occur ONLY at idle or during tip-in acceleration off-idle?

--

Go to Step 4

Go to Step 6

4

<LI type=1>Start and run the engine until the engine coolant temperature is more than 82°C (180°F). <LI type=1>Turn OFF all accessories. <LI type=1>Hold the brake pedal in the fully applied position. A hiss will be noticeable when the brake is fully applied. <LI type=1>Place the transmission in Drive. <LI type=1>Idle the engine for more than 30 seconds. <LI type=1>Record the Balancing Rate Cyl.1-8 parameters from the scan tool while the engine is at idle speed.
Repeat steps 2-6 with the transmission in Neutral.

Are all of the Balancing Rate parameters within the first specified range in Drive, and the second specified range in Neutral?

-6 mm³ and +6 mm³

-4 mm³ and +4 mm³

Go to Step 6

Go to Step 5

5

Graph the Fuel Pressure Regulator. Refer to Fuel System Diagnosis-High Pressure Side.

Is the fuel pressure regulator graph normal?

--

Go to Step 7

Go to Step 9

6

Important: The fuel Cylinder Power Balance Test must be performed under the conditions for which the concern occurred. The concern must be duplicated during the test.

Important: Do not operate the cruise control during this test. Cruise control reactivation after the test may cause a brief extreme increase in engine speed.

<LI type=1>Observe the cylinder power contribution or other customer concern.
Perform the Cylinder Power Balance Test in Special Functions.

Do any of the cylinders indicate a different cylinder power contribution than the others, or lessen the customer concern?

--

Go to Step 7

System OK

7

Important: A fuel injector leak into the combustion chamber may result in mechanical damage to the cylinder. If any fuel spray comes out of a glow plug hole during the compression test, replace the fuel injector of the affected cylinder.

Perform the Engine Compression Test. Refer to Engine Compression Test in Engine Mechanical-6.6L

Do any of the cylinders have low compression?

--

Go to Symptoms-Engine Mechanical in Engine Mechanical-6.6L

Go to Step 8

8

Important: Refer to Injection System Components in Engine Controls Component Views. Failure to correctly identify the cylinder positions may result in the replacement of the wrong fuel injector.

Replace the fuel injectors on the cylinders that had poor cylinder power contribution, high balance rates, or a noise/smoke change. Refer to Fuel Injector Replacement.

Did you complete the replacements?

--

Go to Step 10

--

9

Replace the fuel pressure regulator. Refer to Fuel Pressure Regulator Replacement.

Did you complete the replacement?

--

Go to Step 10

--

10

Operate the vehicle under the conditions in which the concern occurred.

Does the system operate normally, with no DTCs or symptoms?

--

System OK

Go to Symptoms-Engine Controls

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

minibike132 · January 6, 2008

But they don't tell us to deny things that would invite lawsuits initiated by disgruntled employees. Here is the real bulliten for that concern.

Document ID# 1962218

2007 Chevrolet Silverado Classic - 4WD

Subject:Improved Oil Fluid Wear Pump Clip - keywords 136 149 246 246EAU 261 263 263EAU housing leak case transfer transfercase #PIP4118 - (04/17/2007)

Models:1998-2007 Light Duty Trucks and Utilities

Equipped with New Venture Gear Transfer Cases RPO NP1, NP2, NP3, NP4, NP8

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Oil pump wear clip P/N 12470559 is broken or out of position. This may cause the pump to wear a pin hole in the transfer case rear half. If the wear is severe the transfer case may be damaged due to lack of lubrication. The clip may fatigue and break. The clip may become loose and shift out of position.

Recommendation/Instructions:

A new clip design has been released. P/N 89059653 is available for both production and service. This new part totally cancels and supersedes the former P/N 12470559. Only the new clip will be available.

This new oil pump wear clip should be used whenever a transfer case is opened for any type of internal service. See photo. GMSPO currently has inventory of the new part.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

Crazebob · May 14, 2008

I have two trucks with the same problem. My dads truck and also my truck have mysterious holes in the transfer case. My truck an 01 1500 z71 has at least three holes that I know of... all of which I just patched up... My dads 03 case in the same truck has at least two holes. All holes are in the rear housing but odd places, bottom, side, top, etc. I have read about this issue on many different forums and most people agree that its an issue with the pump. I have also seen more than one response for a solution being to "get a REAL transfer case." So my question is this. Are there any transfer cases out there that are stronger, more reliable and a direct replacement for the OEM case? or any that will fit, work with the electronic shift and be similar enough to not need extensive replacement of parts or some kind of adapter plate??

Dantheman943 · August 31, 2011

I have an 04 2500hd 6.0 gas and this just happend to me the other day. at first i thought the gasket was leaking because there was oil all over the gasket and all under my truck. Mybe the third time of filling it i notoced the hole and its in the same place as the pics below. I have 108k on the truck but was beat on for the most part.

thx

spagetticowgirl · June 18, 2012

This is exactly what my transfer case looks like with a pin hole. After blaming Walmart for doing it I searched online to find this forum. What I find amazing is that when I called GMC customer service about the problem to ask if I buy a new transfer case instead of a used one because I didn't want this to happen again they told me that there is no recall for this item there for the new ones are just like the old ones. I am very disappointed with GMC for not acknowledging the problem and redesigning to fix the flaw. When I call the dealership service department they all know exactly what I am talking about. Interesting! Anyway, my mechnic is trying to find a "kit" to solve the problem on the inside from rubbing then welding the hole on the outside. PS... We (USA) should take more proud in making the best vehicles on the road like our foreign competitors.

brainpause · June 19, 2012

Anyway, my mechnic is trying to find a "kit" to solve the problem on the inside from rubbing then welding the hole on the outside.

Here ya go.

http://www.merchant-automotive.com/transfer-case-pump-upgrade-kit.aspx

dodge123 · June 19, 2012

Very common problem. I caught mine before it wore a hole through. Get the "pump rub fix" parts and either jb weld the hole or get a new rear case half. My chain was very worn as were the gears so I ordered a rebuilt case with the "fix" already installed. I pulled the case apart on arrival to verify I got what I bought.