Back in late spring I purchased a 1996 Jaguar XJS with no reverse gear off a coworker for $1000. I want to rebuild the transmission with better gearing for acceleration. I am wondering what transmission Jaguar used so I can purchase the correct gears. Thanks

 

 

Thanks! This is exactly what I needed! Now.....any leads on an XJR6 supercharger? lol

 

Nitrous Fox,

I've not heard of any owner who's changed the individual gear ratios on a 4 litre XJS. What were you intending to do, just lower the 1st 3 gears and leave 4th alone? Depending on what type of driving you do, wouldn't it be a lot easier and cheaper just to change the diff ratio to achieve the same end, albeit at the loss of top gear high-speed cruising low revs?

Paul

 

Yes thats what im looking to do. The transmission needs rebuilt anyway

 

In case you haven't thought of this, a misadjusted cable can make it seem like there is no reverse. Before you go to all the trouble of rebuilding the trans, I'd double check your cable adjustment.

 

Much appreciated but I have a transmission failure light in the forward gears now too

 

As far as I know, that is a Check Transmission light, not a failure light. Like a Check Engine light it can be triggered by many things (some simple and easy to fix) and isn't necessarily an indication that a rebuild is in order. The attached might help you diagnose what the problem might be.

 

if you can’t locate alternate sets of gears. You might do the cheap and easy way to get more acceleration.
If you have a 60 series tire get the same size in a 40 series or even a 30 series.
Another way is lighten the car. Remove anything you don’t need. If you look that is a pretty heavy car. For Racing I get mine down to 2700#’s but lose all comfort and elegance.

One final suggestion. Get an EV. They all have very quick acceleration from a dead stop. ( Gas motors make peak torque around 4800 RPM. While electric makes it at 0 rpm.

 

I dislike EVs

 

That’s OK, I love my V12’s and in fact all of my JaguarsI Yes they have flaws but I think they are fantastic value for money.
I like EV’s not for political reasons but because those I know who own them report extremely low operating costs. And price wise they are available new for less money than the average new car sells for. ( and the Tesla model 2 will start at $25,000).
See, every thing I save driving one is that much more I can spend on my Jaguar hobby.

 

I want a V12 XJS next

 

Nitrous Fox,

Maybe give Swallows in the UK a ring who are strong supporters of the Jaguar Enthusiasts Club and also engaged in both their own and client Motorsport prep. I'm sure they would give you some good opinions as to whether other performance improvements of the car is the right route rather than gearbox changes.

Swallows Jaguar Specialist | Servicing, Performance & Motorsport for JLR (swallows-jag.co.uk)

Cheers

Paul

 

Update: I purchased a used transmission. Thanks for all your help.

 

Until the battery needs changed. Just saw a report/video where on the Hyundai Ioniq 5, insurance companies just total out the cars if any damage is sustained by the battery or its case because Hyundai charges $60K for a new battery. I think thats more than the actual car.

 

I’ll be polite and just explain why that can’t possibly be.
EV’s typically have a 100,000 mile warranty on the battery. To get a free replacement the battery has to deteriorate just 20% of its capacity ( leaving 80% good )
Typical life is over 300,000 miles. GM replaced most of the batteries in the Chevy Bolt not because they were defective. But because mistakes were made by their supplier and no record was kept of which ones were bad. ( also experts had told them not to use that style battery).
Modern batteries are massively better than early ones. They take faster charging speeds, have almost no possibility of a fire, give 20-40% more range, and are much more durable.
And even better ones are in the prototype stage.
Realize that with an EV you likely will never have to drive to a gas station again. ( no oil changes either) You’ll spend a few seconds plugging your car in and the charger will turn on after you go to bed leaving you with a full “ “tank” in the morning.
The rare event when you charge on the road, 10-15 minutes will give you 80% of a full charge.
The time and money you save now can be spent on Jaguars and other important things

 

A million mile battery? Reportedly Tesla now has a battery additive's patent that will allow their batteries to last up to a million miles.

 

It might be easier to change the final drive ratio to get more acceleration. Do you really need 150 mph gearing with today's traffic?

HTH, Dave

 

I wound up purchasing a used transmission

 

changing tire aspect ratio achieves the same thing