Pitman Arm Shaft/Sector Shaft Seal Leak

[76LongBox]

Need a little advice/help guys...

The bottom seal on the pitman arm shaft on my power steering gear box has developed a leak after 39 years (go figure huh).

Looking at the Hayne's manual I have, it would appear that the top cover and pitman shaft (aka sector shaft?) has to be removed to change the seal, but some of the seal kits I've seen for sale, like at O'Reilly, do not include the seal for that cover, making me think that it's also possible to change it from the bottom without having to remove the shaft.

I stopped in my local O'Reilly tonight, and one of the seemingly more knowledgeable guys there told me he would recommend just replacing the whole gear box....that his experience has been that replacing just the seal would be putting off the inevitable, and it would just leak again within a few weeks.  Now, that was before he saw the cost of the new (or rebuilt) gear box - $130 or so - as opposed to $10-12 for a seal kit.

So, I'm here to ask what you guys think.  The truck has roughly 160K miles on it since new in 1976.  Engine/Transmission were swapped out about 1 1/2 years ago, but the rest of it is basically original - including the steering gear box.  The truck handles very well, and I don't know of any issues inside the gear box...just this little drip that I'd like to stop.

Any advise/opinions will be appreciated.

[illinoisk30]

Personally I would just change the steering box like the parts guy said. I have changed them before and are not that bad. Two guys is easier to change it, they are a bit heavy and awkward to change yourself. The seal went out for a reason and if there is vertical play in the sector shaft it may take the seal out again. If it is the original steering box I would definitely just change it. It is more expensive but less headaches in the end and better piece of mind.