This is definately a good idea-over here in the UK there are quite a lot of very well-priced used ZF gearboxes on ebay & at breakers which are serviceable. They are priced low enough to keep one in reserve, fit the uprated 'A' drum at leisure with the transmission on the bench & also do the valve body overhaul too.

Then you've got a serviceable transmission with the uprated parts, so as soon as you get the first warning signs that the old one is about to die, then you've got plenty of advance warning to get the reserve transmission fitted & won't have to go to a transmission shop on a tow truck in panic & receive a bill for 1000's...

With old, high mileage cars it's always a good idea to do your homework, visit the forums & learn the vehicle weak spots. There is always going to be an adequate supply of good used parts on ebay or at breakers, so you can just keep the 'essential' parts in reserve at low cost.

My other old BMW had a worn steering box advisory at the last MOT-I couldn't tighten it up any further with the adjuster, so I kept an eye on ebay & then the right unit turned up last month on ebay for around $100. New ones are ridiculous money-something like $2000...

Cleaned up the new reserve box, checked for play & tightened up the adjuster-then put it in a clean box until the spring when the weather improves for working outdoors MOT isn't due until October, so there's loads of time to fit it.

 

Thank all of you for the advice - Keeping a new transmission ready to go is an excellent idea. I'm definitely going to start working on that.
I have no problem working on the car, it's just right now I have to drive about an hour to get anywhere I can even take anything apart and the garage is currently taken up by a vr4 hah. I'll order parts this week and hopefully drive out this weekend, pending it's availability, and then take it apart in the order everyone here is recommending.

I was also considering keeping an ls1/460le ready to go for the car. They make a kit requiring little fabrication/wiring and it's ready to go, and would be about $4k said and done. It would be a relatively easy thing for me to do. Is that sacrilegious??

 

"Is that sacrilegious??"

YES.

There is nothing wrong the the Jaguar engine design AT ALL- once the leak is stopped, you should be good to go for 100K+ miles.

 

ALRIGHT - to revive this thread, the car sat for a couple months due to nowhere to work on it.
There was a supposed timing cover leak coming from the harmonic balancer seal or the timing cover seal.
I finally was able to use my buddy's garage - here's the result:

It wasn't the timing cover or balancer. It was the oil cooler block-off plate. There is an oil cooler block off plate on passenger side below the harmonic balancer.

Here is the actual block off peice. There are two little "pipes" held in by this cast piece on the front. This cast piece is held on by a single bolt.



Here is a picture with one "pipe" removed and one installed:



Here is the one of the little pipes - As you can see - the pipe has two O-rings on it. In person, it was clear that they were the source of the leak as the rings were permanently compressed and out of round.



This cost about $8.00 in O-rings and different bolts from a local hardware store. #15 O-rings (4 of them) and a series of different length bolts to basically press the O-rings back into place on the car as they were a very tight fit.

Thank you for everyone for your advice, and I apologize for getting back on this so late! If you have any questions at all please feel free to ask.