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First post here, and a question about XJ6 transmission change...

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Ron Engels

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Hi,

My name is Ron Engels and I live in The Netherlands.
Two years ago I bought a 1973 XJ6 4.2 SWB auto. This is now my every day drive, and I'm happy to say that it hasn't let me down once. It came from Southern Italy where the climate is warm and dry. The body is all original exept for a respray and pretty good, although two years in this moist climate have made a few minor rust spots become more "active".
Gearbox and engine are untouched, at least by me, and are working very well.
I had the complete brake system overhauled, the front and rear suspension, and the steering. Since mine was delivered in Europe (Italy) it had a short end gear (is that what you call it?), so I had that changed together with the diff. for one out of an XJS. That makes it a lot more comfortable on the highway,and reduces the fuel consumption a little (Important in my country, where two full tanks will set you back about $130).
However I've read somewhere that in the U.S. it's not uncommon to have the gearbox replaced by a more modern 4-speed, GM if I'm not mistaken. I would never change the engine myself, although I'm still considering converting it to run on LPG, but a better gearbox may be a good idea. Is there anyone here that has experience with this or could tell me where to go for information?

Ron.

XJ6.jpg


[ 02-17-2004: Message edited by: Ron Engels ]</p>
 
Welcome to the forum Ron, that is a beautiful car you have there.

As to the transmission, I think that you have a Borg-Warner unit. The GM transmission is, I believe, the GM40 unit that was installed in the later cars, late Series II and III. I had a 1976 XJ12 with the Borg-Warner, and it served me very well. The GM40 is reputed to be a better transmission, but the earlier B-W was still a good, reliable unit. If your present ransmission is performing well I would suggest leaving well enough alone, but if you can't live with it any longer, then a reputable Jaguar specialist can advise you on pricing etc. The Jaguar Enthusiasts Club in the UK can no doubt recommend someone. Since the GM40 was fitted to later XJ6's, maybe it won't be too difficult to swap the transmissions. Good luck.
 
Hi Ron,

I think the GM40 trans that Steve is refering to is actually a GM TH400 which although "bullet proof" is only a 3 speed automatic, with out a lock up converter or overdrive. I dont know nearly enough to even think I have the final answer for this one, but I would think it would be fairly easy to adapt a GM 700R4 trans to your car. 700R4 has OD as well as a lock-up converter and is also very reliable. I have no idea how available one of these would be where you are though. Possibly there would be another similar unit in your neck of the woods that would be more readliy available.
 
One beautiful Jag. I have a 1996 with the GM trany and I get 17 mpg in town, and 23-24 on open highway. very smooth.
Harvey Nelson
 
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