Good Day fellow lump-ists!

As some may recall, I inherited a lump-in-progress which was done very well with a couple of unfortunate exceptions. So far, I've been able to work through many of them and have the car running quite well. It was my daily driver through the winter in Montana and aside from water intrusion causing the door locks to freeze a couple of times, it performed more than admirably.

So now comes the time to show it some love and fix some of the little oddities. The one that is annoying me the most right now is the bodged shifter. Can anyone shed some light on what it takes to adapt the factory XJ6 shifter to a TH400 (specifically, mine is a 700R4)? The issue I am experiencing is that it takes a good bit of force to get the box all the way into park, reverse is right about at the "neutral" detent, neutral at drive and drive somewhere between 2 and 1. The stick will not pull below drive so manually selecting a lower gear is impossible. It is also very fiddly and difficult to shift. Not at all smooth like a factory box or like some other lumps I've experienced. Is this likely the result of a damaged assembly or an incompetent mechanic? Does any of what I've said even make sense?

 

You need to put your car information in your Signature so we can help more
easily.

Normal problems are the actual shifter cable, could be "welded" inside or wrecked due to a lack of ground cable from engine to frame? Some PO's do not understand this very great need and do not install/replace the big braided cable. PO might have used an improper shift lever that just does not have the correct length or "leverage" or both things could be wrong.

I have several grounding cables on my cars. Grounds are the biggest electrical problem with Jags other than just dirty or corroded connections. You need one from the engine to the body and body to the frame. These little cables can be purchased at local auto parts stores for about $6.00 each or made up out of copper wire and crimp on ring connectors. The big cable, usually attached to the block near the starter and then to the frame, should be a quality braided cable.

 

The XJ12 saloons and also the XJS V12-engined cars used the TH400 tranny from around 1979, as far as I know, but I think Jaguar called it the GM400. So a shift mechanism from either of these cars should work in your XJ6 car as it will be a straight bolt-in job.

 

Roger, you mean you can't just telepathically determine what it is I drive? What good are you then? I feel a bit of a heel for that oversight. I honestly have no idea what I was thinking not posting the details when there are just a few model years, near infinite engine/trans possibilities with a lump and nearly 30 years of history over the "series" cars. I'd chalk it up to being a newbie but I'm only new to Jags, not autos on the whole.

Anyway, apology aside, for the sake of this thread it's a 1986 SIII VDP with a Chev L05 5.7 backed by a 700R.

I never even considered the cable having basically fused itself whilst acting as an earth. It makes sense and given the 22ga wing-to-block earth wire that was installed when I bought the car, I'd hardly be surprised if that wasn't part of the issue. I'm trying to recall if the big braid was connected when I recently did the starter or not. I remember seeing it down there, but I don't recall if it was hooked anywhere but the car. I think it was but the connection at the body looked pretty dodgy. That'll be something to check.

As for the shifter itself, I'd originally assumed everything was stock Jag, but I'm beginning to question that. The basic assembly is (the lever, indicator bezel, etc) but the detent plate looks to have been re-fabricated. Clearly that will require more investigation but I think I'm going to have a look at the cable first. I know the engine had/has earthing issues and that may well be a point of failure. Thanks for the tip!