Transfer case Front Output shaft seal

[Tac Map Mike]

Hi there, I just picked up an 1989 k1500.
I’m ok doing a lot of the work myself but I didn’t feel like tackling the intake manifold gasket so I brought it in for that and an inspection. It does need some work, steering, CV joint, front axle seals, etc.

It also needs the front output shaft seal of the transfer case done. I did do a forum search but it did not yield much.

Is it as simple as it looks? I couldn’t find a great video. Any one have a step process?

Thanks!

 

[Nad_Yvalhosert]

Front "output shaft seal" of what unit?
T-case?
Rear differential?
Power steering pump?
Water pump?

All those items have a forward facing shaft of some sort... Specificity please.

Technically, the front differential outputs are on the left and right sides, the p/s gearbox output is on the bottom...

Seeing as you posted this in the "Transfer case" section, have you looked into a rebuild kit for the (I assume) NV241?

After 19 seconds of research on Rockauto, I found the least expensive seal for you:

More Information for SKF 18771

Changing that seal is just like a pinion seal. Gotta remove the yoke first, and torque it properly when you're done.

 

[Tac Map Mike]

I will edit. Transfer case.

 

[Tac Map Mike]

Finally got a chance to look at the seal. The actual seal itself looks ok to me…is there another seal in the yoke itself?

Also, I don’t see a Center support or hanger bearing - do these trucks not come
With one?

Thanks

 

[Tac Map Mike]

Or am I looking at the wrong shaft? Is this the front transfer case output shaft?

 

[xXxPARAGONxXx]

Also, I don’t see a Center support or hanger bearing - do these trucks not come
With one?

Thanks

Mine has one. However, I don't think all 4WD GMT400s have a center support bearing. I think it's used for those GMT400s with longer rear driveshafts, which would be used on the extended cab and crew cab body styles. The regular cab is probably not equipped with one.

If I recall, you have a regular cab, so you probably have the slip yoke coming from (i.e., splined to) the transfer case rear output shaft which is connected by U-joint to a single-piece rear driveshaft (propeller shaft), which at the other end connects via U-joint to the rear axle pinion shaft yoke.

You must be registered for see images attach

 

[xXxPARAGONxXx]

Or am I looking at the wrong shaft? Is this the front transfer case output shaft?

“Front” modifies output shaft, not transfer case. It is the transfer case front output shaft yoke. To say “front transfer case” implies a “rear (i.e., another) transfer case”.

There’s a front output shaft and a rear output shaft inside the transfer case.

At the age and mileage of your vehicle, all your seals likely need to be replaced, for whichever ones have never been replaced. You should expect nothing less. It’s rubber-like material, and it’s going to degrade over time.

 

[Tac Map Mike]

Gotcha. Thank you. See when it’s the transfer case front output seal leaking - is it the pictures in the first post or second post. Thank you!

 

[Nad_Yvalhosert]

Post #5 is the front out seal, and it's damp.
Post #4, pics A&B, are of the rear output seal, and it's dry.
Don't you know your front from your backside?

 

[packer0440]

There is also a spline seal for the front driveshaft. I have no idea if they go bad but not a bad idea to replace it