I'm hesitant to mention this because I'm not sure if I'm right, but....

I think the Getrag 290 is the same as a New Venture 3500....or at least a kissin' cousin.

Just throwing the idea out there on the odd chance it'll be useful to someone

Cheers
DD

 

A Getrag is a Getrag. Nothing really "Jaguar " about it. The last real Jag manual was a 4 speed designed by Mundy and used in the E Type. Getrag is a German company that had a partnership with Ford and just happened to make manual transmission in various facilities all over the world. Additionally there is nothing "Jaguar" about using an adapter plate and bolting a flywheel to an automatic flex plate. That's something Jaguar or any other OE wouldn't do in a production scenario.

What do you mean ?... "fiddle with the clutch"

As for Getrag failure... who knows how long a indivual transmission from a breaker will last. Who knows how well it shifts? Or if it will make noises. It's a gamble and a un-calculable risk becasue the trans could have 20,000 miles or 200,000 miles,perhaps even more...one never really knows with used parts. With a T56 you know... its new. 0 miles,in the box, and with a warranty.

The T56 is big at the tail end and will require 4 inches removed from the trans tunnel but for that you get a bullet proof transmission with super short throws and world class action. Here in the USA Getrag's are known as fragile and usually found behind 6 cylinders. This also why the BMW guys gobble them up and pay big dollars for a used unit. They fail when pushed and the BMW guys have no choice.

It's true... the T56 uses a non OE parts and that's a good thing becasue as I stated before you have choices and lower costs. The broad adoption of the T56 allows for many release bearing and clutch material choices. With the T56's standard output shaft its quite easy to choose an off the shelf steel shaft or aluminum shaft. Choices are good for an enthusiast... and being stuck with a 1 off flywheel and soon to be out of production OE parts is not a virtue, it's a trap.

I would argue a T56 conversion is more like Jag would have done becasue it uses an actual V12 manual flywheel and also uses a 10.5 inch clutch disk just like Jag used on the E Typ, and a removable bell housing just like Jag did. The Getrag conversion uses a smaller clutch disk designed for a 6 cylinder.

As a forward looking concern future serviceability of a T56 conversion will be lower cost and parts will be highly available. For example....

Premium standard clutch disk... 49$
Hydraulic through out bearing... 99$
Standard 1310 u-joints... 12$

As i see it...The Choice really comes down to a set of ideal situations Verses a set of risks, should's, hopes and wishes. T56 offers durability, low cost of installation and ALL NEW PARTS. Getrag conversion is a collection of adapters, some new and some unknown used parts. Doing any conversion takes time and money so anyone making this choice would be well served by all new parts.

 

I Agree with CSA on Tremec vs Getrag transmission conversion on the XJS. My only stumbling blocks were clutch master cyl size & ECU (stalling between shifts), that was fixed by Roger Bywater's AJ6 in the UK.
The only thing IMO is the pro's and con's of using 5sp vs a 6sp. Cost, Tunnel work,. Do you really need all this for two overdrive's with 2.88's or even 3.54's diff. If you really NEED a 6 speed go to a Richmond with 1 OD & Long shifter

 

Richmond no longer makes the 6 speed so that's a dead end. They still make a street 5 speed. I dont have any experience with the Richmond Trans as I chose not to go that route. Here's why... The Richmond costs more and the default and only shifter location is very problematic on a XJS. It's way too far back and the shifter assembly with it's 3 rods would stick up past the ski slope.

Also the linkage rods are external which created all shorts of clearance issues. The Richmond T5 is more for a mussel or race car with the trans exposed. Too bad becasue the gear ratios are compelling for the 2:88 diff. The Richmond is fine for a no holes barred more race like street car but not a Jaguar street car.

The T56 is a good enough fit and the T56 has a no-additional cost shifter option which provides the perfect location. It also has the perfect EO style ratios for a 3:31 or 3:54, both are available.

I haven't experienced the stalling issue but fully accept each install is slightly different depending on year to year changes. I hook the park/neutral switch to the clutch pedal. Usually have to do this for starting anyway. Did you still have that issue with the P/N switch hooked to the clutch pedal?

 

I've never had to start the car doing anything with the clutch pedal. The trans/shifter must be in neutral though. The engine will not turnover when the shifter is anywhere but neutral. In the event of a stalling when starting out you must return the shifter to neutral, turn the key to the off position, than turn to restart.
Rodger Bywater told me the stalling between shifts was caused by the "fuel override" in the ECU. As said, A6 reworked the ECU to cure this. RPM now drops to around 500 between shifts.

 

Possibly, not heard of this though.

 

Are the transmission tunnels on the pre and post facelift XJS the same size?

 

Some may be interested is this. This is how I do the pedal. Notice the HUGE bushing and bolt. This and the hollow tube pedal arm allow for no loss of feel related to fulcrum friction and reduces any numbness from pedal weight. There is no other solutions that is this light and this adjustable.

This with pedal and a hydraulic release bearing it feels as if your brain wired directly to the clutch

.

 

Almost forgot, Take that brake light switch off the brake pedal BEFORE removing the pedal box . It's almost sure to brake if left on. They are a "pure junk" . I'd really like to know what Jaguar was thinking on this thing

 

What I am wondering is being the XJS initially starts off with a GM TH400 Auto, would swapping a 6 speed from say an early 90's Corvette work? Not sure if they make manual transmissions where you can swap out just the bell housings or not. I know when I had my TH400 rebuilt, the place that did it said it would be cheaper for me for them to just swap it out with one they already redid, but the bell housings were different between the two.

I too am looking to convert mine to a manual. I want the 6 speed though.

 

Too bad, its not just that simple. Although Jag used a TH400, its a variation. The case of the transmission is unique. Everything inside that case it typical GM TH400. Also the 90's ZF transmission is well loved but very expensive to buy and repair. Any one found would surely need some rebuilding. They are so difficult and expensive to repair that some of the Corvette owners resort to doing a T56 swap, which some people prefer. Used ZF 6 speeds sell for 2/3rd's the price of a brand new and tight T56 that come with a warranty.

That said, I do manual conversion using just 3 unique parts.
Driveshaft,
Bell housing
Pilot bushing.

Just 1, the bushing, would be considered a consumable and is low cost (15$) should you need one in the future. You're not likely to need a new driveshaft or bell housing for the life of the car.

 

I believe that the only thing I would not know even where to begin to look for is the bell housing for my car. Or is there someone out there that makes them to be bolted onto the T56?

 

Here it is, in the flesh. I have all the other parts at hand too. If you serious and are willing to put the dollars behind the dream it can be done and done well.





1 bell housing.



T56 is a great fit

 

Is there anyone in specific you get the T56 from? I have been trying to find a place, but they all cater to Chevy, Ford Dodge or Jeep only. I mentioned Jaguar and they shy away. I did find one through Jeg's though. Would this one work?

http://www.jegs.com/i/Hurst-Drivelin...kaAjodEALw_wcB

 

Might work, Check the part number against some of my other posts. No other info or consulting unless you are a paying customer. PM me contact info when you're ready.

 

I still can't justify going through all this for a T56 six speed with two OD's over a five speed with one OD, UNLESS a lot of Wyoming, Montana, etc type driving is a priority and two overdrives are a must. Even then the cost and tunnel modifications must be considered . Just my opinion

 

There's nothing to justify. It costs no more and perhaps less to use a T56. The T56 itself costs more than a TKO600 or used Getrag but other aspects of the conversion are less expensive. So if you look at the project as a whole and actually crunch the numbers of actual parts needed as I have done, then in the end a new T56 is better in every way. Closer ratios help keep the V12 in it's sweet spot.

Its widely accepted that a 2 valve fixed intake and valve timing engine has a narrow ideal power band of about 1600 RPM. The Close ratio 6 speed helps keep you in that range.

A close ratio T56 is best with a 3:31 or 3:54 gear. 6th gear is very close to 4th with an Automatic. At this point there is no viable manual transmission option to use with the 2.88, unless you want a used junker shipped from over seas. That's cost way more than a new T56. So anyone considering a T56 or even a TK600 should plan on a diff ratio swap.

I have 3.31, 3.07 and 3.54 diffs in my possession and can also assemble a diff with any ratio or locking bias a sporting drive would like using Dana 44 parts. An all new Dana 44 gear set and locking carrier costs about the same as rebuilding with Jag parts.

As for the tunnel mods. it's minor, you could save the piece and weld it back if necessary.