Events have come together in such a way that I was able to acquire a Getrag 5-speed gearbox and the necessary adapter plate to adapt it to an E-type bell housing and install it in my aging but still excellent Series III XJ6. In the Spring, the car passed the 300k mile mark, and is still running well, but I had always felt that the Borg-Warner 66 is a resource drain on the XK engine, and a manual gearbox would be a very positive improvement. On this page, I will put some of the photos and some comments about the job so that anyone who is contemplating a similar job can see one of the ways that it can be successfully done. Clicking any photo will bring up a larger version. Take a short test ride by watching the video, then if the interest is piqued, read on to see how it was done.
Started this project after the car had traveled 300,000 miles, and at times I was doubting the wisdom of spending so much time on such a mature machine. Fortunately, my courageous side won, and I proceeded. Found a flywheel from a 3.8 E-Type, a friend made an adapter to adapt the Jaguar drive shaft to the Getrag output flange, and I bought a master cylinder for the clutch for a MK II. More on this later
The tranny is a Getrag 265 sourced from a 1981 BMW 528i. The car belonged to a friend and I was actually able to drive the BMW before it was parted out, so I knew what to expect from the tranny. I installed studs in the bell housing to attach the tranny to the bell housing. Also had spare adapter plates made for the bell housing and drive shaft, in case they were needed later.
The Jaguar XJ6 pedal box has the boss for the clutch master cylinder in the casting, so it is possible to use the standard pedal box with a few modifications. While I had the 528i I noticed that it's pedals were practically the same length as the XJ pedal, and I felt that with a little bending and cutting, I should be able to make a working clutch pedal from the BMW parts. The BMW pivot was too wide to fit into the pedal box, so I shortened it, and ground away some metal, then heated and bent it so that it was pointing in the correct direction. After cutting of the BMW pedal, I had a piece of 1/8 steel cut to the shape I needed and welded it onto the pedal arm. The push rod arm from the BMW pedal was in good position to work the master cylinder, so I didn't have to change it at all. Then I cut the Jaguar brake pedal to closely match the new one, ( it is actually a bit shorter than the one that I had made, but works ok ), and installed MK II pedal pads.
One of the things that I really thought would be a problem is the speedometer drive. After considering, and discarding, several plans, I decided to have a look at the Borg Warner speedometer drive to see if there was something that I could do with it. As luck would have it, the Getrag drive housing is 25mm in diameter, and the BW housing is 1 in. (25.4mm), so we put it in a lathe and removed the .4mm to make it fit into the Getrag. Then in another piece of good fortune, the shaft of the BW gear is slightly larger than the Getrag shaft, so we were able to drill the BW shaft to accept the Getrag shaft. This gave the correct threads, correct gear, and the necessary length to connect the XJ speedometer sensor unit. The gear ratio for the Getrag is slightly different from the BW, and the speedo reads about 4% low, but I recently saw a device for correcting motorcycle electronic speedometers that I think will work for me. I'll order one and see if it works.
As it turns out, the Getrag pilot shaft spline accepts the standard Jaguar clutch disk, but the pilot shaft is only 12mm in diameter, smaller than the Jaguar standard, so I had a pilot shaft bushing made to fit I was unable to use the MK II clutch master cylinder, because it was just too tall. I trimmed down the mounting boss on the pedal box as much as I dared, and the top of the master cylinder (which by the way is where the outlet connection is), was conflicting with the bonnet. My plan was to drill a hole into the inner part of the bonnet to give me space, but second thoughts sent me back to the E-Type and I used a master cylinder from that. Down side is that a remote reservoir is necessary, but I worked that out also.
The rear transmission mount is a puzzle with the Getrag. There are support flanges about mid way down the body on either side, and one on the right hand side rear. What I ended up doing was using parts of the Jaguar mount and parts of the BMW mount. I disassembled the Jaguar mount and used only the front part of it. I welded a nut onto it that would accept the BMW mount and screwed them together. This aligned with the rear mounting tab on the Getrag, and seems to be adequate for the way that I drive the car. I am closely watching this as I put on a few miles to see if I need to make changes here. In the final picture, we have the rear of the gear selector lever. I used a rubber mount similar to, but much smaller than, the transmission mount to attach this to a hole that I drilled into the transmission tunnel just to the rear of the access plate.
The shifter was the next challenge. The XJ has a removable access plate in the top of the transmission tunnel. By removing this, one can gain access to the area where the shifter mounts to the transmission. I trimmed 2.5 inches from the shifter plate and the shifter rod, to move the shifter forward. BTW, it looks as though I actually should have taken 3 inches, because the shifter is still a bit too far to the rear. I would be fine if the shifter came straight up from it's pivot, but the shifter is actually bent back toward the rear of the car. I considered trying to straighten this, but at the time I didn't know exactly where things were going to fit when I put it all back together, so I left the bend in. If I had it to do over, I would straighten the shifter. Once I had this all together, all I had to do was cut a hole in the access plate and reassemble everything using the BMW foam and rubber seals from the 528i.
Then it was down to the shifter itself. I wanted the nice thin shifter and the knob like the E-Type uses. The BMW shifter is a hollow shaft that fits onto a couple rubber bushings that are themselves slid over the shifter shaft seen in the previous set of pics. The E-Type shifter is a solid shaft. What I did was cut both of the shifters to give me the length I wanted when I used the lower part of the BMW shifter and the upper part of the Jaguar shifter. I then threaded the inside of the hollow lower part of the BMW shifter, and cut the bottom of the upper part of the Jaguar shifter down to where I could put threads on it that would fit into the newly threaded BMW part. I then screwed the two pieces together with a bit of Loc-tite, and had myself a Jaguar shifter that would fit onto the Getrag shifter stub.
The ski-slope is next. I was thinking that this was going to be a bit of trial and error, and for my first try, I cut a piece of aluminum to fill the rear part of the slot where the automatic shifter lived, and attached it with JB-Weld. Then I covered the lower part of the ski-slope with black vinyl. Turns out the first try did the trick
I found a black vinyl door edge trim to go around the shifter opening and pushed it over the edges of the glued in E-Type shifter gaiter for a nice finishing touch.
I have a couple problems that are worth mentioning. First is the starter. Because I was using a 3.8 flywheel/ring gear with the 4.2 bellhousing, I had a problem with the larger diameter 3.8 starter gear meshing with the flywheel. The difference in diameter of the 3.8 starter gear and the smaller 4.2 starter gear means that the starter is actually mounted closer to the ring-gear on the 4.2. To compensate for this, I had a new plate made for the starter that would move the starter further up the ring-gear to the point where it would properly mesh. I knew there was a difference in these starters and the bellhousings, I just let it slip through the net.
Second, my new clutch pedal was too long, and would contact the floor carpet before it would fully disengage the clutch. I just trimmed of the bottom edge of the pedal and it works well now
Third, the shifter is too far back toward the cubby box on the console. I need to move the shifter plate further forward, and shorten the shifter rod a bit more. I think just shortening the rod might do the trick, so I will try that first. This tranny also has the famous Getrag slop in the shifter. I have seen aftermarket repairs for this for the BMW's. I can probably use one of them to solve this problem. In the mean time, it is more than adequate as it is, and quite enjoyable to drive.
Special thanks to:
Art Ford and Charlie Mitchell for
machine work most excellent,
and the folks at
Carolina Drive Line, Spartanburg SC, for a drive shaft that fit perfectly and ran true.
In the US the Jaguar Sedans are known for their comfort, speed (not too quickly though) and unreliability. Elsewhere they are also known for their sportier side. As a luxury sedan the automatic transmission is something of a given, but as a sports sedan, the 5-Speed is far more acceptable and some cars were built with factory 5-Speeds. I had to take matters into my own hands though and the results are documented here. I have been driving the car with the 5-Speed since 2010 and have covered nearly 70,000 miles. There have been a few hiccups along the way, the only one worth a mention is the throw-out bearing, but otherwise it has been reliable and a pleasure to drive.