Transfercase Output Seal Leak

[alz]

I own a 99 OBS Suburban with the Np246 t-case, 129k miles. I replaced the rear case 1/2 along with a Kennedy pump plate because I had the infamous pump rub issue. Ever since replacing the case half, the output seal has leaked. I have replaced it twice with quality aftermarket seals with no luck. Is there something else that keeps the fluid from leaking here? I do park on an incline in my driveway, but that didn't seem to bother the original seal. My local dealer wants $75 for the OEM seal. I will pay it if that fixes the problem, but don't want to throw away money on another no fix solution.

 

Any ideas?

[BrockwayMT]

Is it leaking between the seal and yoke and the seal and the case? If it's between the seal and the case put some RTV or #2 Permatex between the seal and the bore in the rear case being careful not to get excess sealant in the case.

 

 

If it's leaking between the seal and the yoke you need to buy a new slip yoke. It probably has a groove in it from 129k miles. The old seal was probably happy in it's groove. Tolerancing in the new case and new seal probably has the seal in a different spot in relation to the groove in the yoke that is chewing up the seal. I know you don't want to spend a C note on a new yoke but a new yoke and new seal should fix the problem.

[alz]

It leaks between the seal and yoke. So, I guess the next step is a new yoke and another seal. Unless anyone else has suggestions.

[gmtech4]

what else is there to do ?not much,geta new u-joint to.

[alz]

Anyone have a part number for me? In need of a slip yoke.

Rear axle is 9.5, Saginaw

T-case is NP246

99 K1500 Suburban

[gmtech4]

parts stores or dealer has that

[alz]

The drivetrain shop says they need dimmensions or they may be able to reference through a part number. I hate to call the dealer and ask for a part number. They know they are not making a sale.

 

Is 12477702 the correct part number?

[gmtech4]

just call up a dealer and ask for the yoke and give the last 8 of your vin,poof ,thats it ,don't forget the u-joint,forget the driveline shop

 

1 hr labour ,thats it !!

 

have them order the yoke and the u-joint will be in stock(better be)

 

make an appt ,get er done

[Mike G]

In the past if not in a hurry, I have sent an email to GMPartsdirect.com, they will tell you the part number, also based off your vin....

[alz]

Thanks, I may give that a try.

Not to upset anyone, but I refuse to pay $225 for this part from my local dealer. They wont give me any kind of break. I don't have a problem using OEM AC Delco parts. I'll try an online GM dealer.

[BrockwayMT]

That's way too much. I'd guess 100-150 from the driveline shop. Just take the shaft out and take it to the driveline shop. It's only four bolts. After they measure the yoke you can put it back in until the new yoke comes.

[alz]

The R&R for the driveshaft isn't a problem. Done that many time replacing the t-case and the seal and ujoints. I am pretty sure I've come up with the correct part number and I will take it to my local parts supplier and see if they can match it up.

Part no. 88963576

[rickmac]

The R&R for the driveshaft isn't a problem. Done that many time replacing the t-case and the seal and ujoints. I am pretty sure I've come up with the correct part number and I will take it to my local parts supplier and see if they can match it up.

Part no. 88963576

 

 

if its leaking oil through the cap in the back of the nucle so the oil is dripping off the universal joint just clean the cap wit brake cleaner and seal it with silicone thats what was suggested to me and it worked just fine

[alz]

No. It is definitely leaking from between the seal and the yoke.

[aja72]

Leak from the transfer case is a common problem and it need to be solve out as soon as possible. If the leakage is long duration it can damage your transfer case otherwise your trasmission can get destroyed. First of all you need to find a leak and check out the catalytic converter. Once you know the place of leak. To fix the transfer case, remove the down pipe. You will find the mounting point of the transfer case highlighted with white line. The drain plug has purple arrow painted to it while the fill plug has a red arrow. Remove the case from the car for better visibility. Get a 24mm socket to drain the case from the base drain plug.