The 'E' Type Forum

I have a getrag 5 speed box from a 3.6 1985 XJS.
Anyone know what else (aprt from propshaft) I may need to fit this and if any other mods are needed in order to fit?

Just looking for a bit more relaxed driving whilst touring Europe next year. Incidentally my car is a US import so has quite low ratio diff I think - anyone know if there are any identifying marks anywhere on the diff.?
cheers
Mark

jmgtaylor wrote:I have a getrag 5 speed box from a 3.6 1985 XJS.
Anyone know what else (aprt from propshaft) I may need to fit this and if any other mods are needed in order to fit?

Just looking for a bit more relaxed driving whilst touring Europe next year. Incidentally my car is a US import so has quite low ratio diff I think - anyone know if there are any identifying marks anywhere on the diff.?
cheers
Mark

There should be little tag attached to the diff with two numbers on that when you divide together give you the ratio of the diff. (Number of teeth on the crown wheel and number on the pinion) failing that you'd have to count the teeth yourself. E.g. For the 3.07:1 diff the tag reads 43/14. Most US spec cars come with quite a high diff ratio (3.54) IIRC

jmgtaylor wrote: - anyone know if there are any identifying marks anywhere on the diff.?
cheers
Mark

You shouldn't even need to get under the car. The speedo is marked on the dial, just under the trip digits, to match it to the diff ratio. It should say 1312 to match the 3.54:1 diff that almost all US S2's had. If the car had been ordered with the 3.07:1 the matching speedo would say 1120 or if 3.31:1 it would say 1216.

This assumes that the diff has never been changed during the life of the car of course.

Cheers

Mark

jmgtaylor wrote:I have a getrag 5 speed box from a 3.6 1985 XJS.
Anyone know what else (aprt from propshaft) I may need to fit this and if any other mods are needed in order to fit?

Can't be done, sorry, not even on a 2+2. Is yours a long wheelbase car? 6 or V12? This is the S2 list so I'm assuming it's a six at least.

It can't be done at all on a short wheelbase car using the 265 long tail Getrag you have. Even on a 2+2 or S3 OTS it can't be done without serious tunnel modifications and clutch mechanism mods, depending which engine you have and bell you use. Your problem is the tail is so long the thing projects deep into the closed tunnel and you'd need to cut away the tunnel cross member between the seats, which is structural. Then there's the asymmetric rear mount, which would be a bear to fit to a symmetrical E-type floor, even using the XJ-S offset mount (too bulky for the silencers to fit).

Being a 3.6 box rather than a 3.2 or 4.0L 290 version, you can at least unbolt the bell and buy an adapter ring off eBay to bolt it to a Jag bell. I've got a couple of steel ones - alloy ones aren't tough enough for the threads to stand abuse IMO. Yeah, I know, with a welding torch and big enough saws and hammers, anything is possible. Still, save yourself grief and sell the box to someone with an XJ-S or 87-97 XJ that can use it. You need either the short tail Getrag from a BMW or a T5 that you could get rebuilt to short tail or medium tail by someone like Elite Racing Transmissions in Stoke. I've got both and would only countenance the longer tailed T5 in my V12 XJ, which is a bigger car.

Pete

Pete, is this the type of Getrag you say is suitable?
http://www.ebay.co.uk/itm/BMW-Getrag-5s ... 2ecf679519

If this is and then overhauled by someone like Elite Racing what else is needed to fit it to an S2 FHC or 2+2?

It might help Mark (and maybe me) know whether is worth trying to do the upgrade to a five speed box in a home workshop, or just sending the car to someone and paying them ?5000.

Geoff

Hi Geoff
I have fitted a E Type Fabrications 5 speed gearbox to my Series 2 FHC in my normal garage. Hired an engine hoist to lift out the engine/ gearbox. Swapped the gearbox over, fitted new clutch, put back in. Fairly simple really.
I would suggest that buying a new box with a guarantee is better than buying something unknown and getting it overhauled.
I have had the box in for a couple of years now and am very pleased with it. :D

Gfhug wrote:Pete, is this the type of Getrag you say is suitable?
http://www.ebay.co.uk/itm/BMW-Getrag-5s ... 2ecf679519

The photo is terrible and appears to only show the top half, but no. No Getrag with an integral bell can be used. That looks like the 290. I don't know the exact application of the one that can be used but not only does it have a detachable bell (needing only an adapter to fit it to a Jag bell) but it is also way shorter than the 265/290 fitted to XJ and XJS cars. Even then, you'd need to fabricate a mount, a propshaft, a gear lever remote etc. and relieve the cross member inside the tunnel even then.

Unless you are an expert fabricator it is beyond the average home workshop in my view. If you ARE good enough, you will know my gereralisarion doesn't apply to you, but in that case I sense you wouldn't ask the sort of questions you are asking. So no - either find a used kit or buy one from a known E-type five speed source who should have everything. DIY is feasible with a good kit as Roger said. Inventing and developing parts for a DIY kit isn't. AFAIK, only the MC Wilkinson kit used the short Getrag. It's not that great a box but it's OK. You'll never see one on eBay described as a Jag box as it was used in BMWs not Jags. Elite will sell you a complete kit for less than 5k and you can fit it yourself. Ask for Rob Swift and perhaps he'll remember me.

Pete

Thanks Roger and Pete, pretty much as I had expected, better having a new box than an old one you don't know what sort of boy racer has abused.

Drove a five speed OTS before buying my FHC and it was nice to have that extra gear.

Hi,

Not sure about the Early cars, but you can fit a long Getrag 5-speed to a Series 3 - I know because I have done it, including making my own gear-lever and linkage to allow the lever to come out in the correct location, using an original manual gearbox style centre console. No gear tunnel modifications were necessary; just to be clear, I was converting an Auto car and I believe there may be differences in the tunnel of six cylinder cars, but possibly not the V12. I also used the original gearbox tunnel cover (from my auto, but cut and welded to clear the new linkage). This of course is a modification to the metalwork, but since it is a bolt on part, I don't count it as a full blown tunnel modification.

I didn't use a kit, but was lucky to find a V12 bell housing for the V12 to Getrag that did not require an adapter plate - they are out there but hard to find. everything else was home build.

However, common opinion is that the Getrag is not particularly suited to the Six cylinder, but is OK for the V12.

Regards,

Interesting. Was it a TWR bell from a converted V12? What did you use at the back?

Yes an auto tunnel (i.e. long wheelbase car) is easier and ultimately anything is possible, especially if you find a trick bell housing but how did you organise the clutch hydraulics? Presumably you couldn't use V12 parts and went for a concentric hydraulic throw out? Or did the bell have provision for a forward-pointing cylinder like Getrag bells do but on the wrong (left) side?

The gearbox mount on a long Getrag is different and several inches off centre. Didn't that cause fouling problems as well as having to make up a plate and drill the floor?

How did you do the propshaft? Was it shortened and with a spline fitting direct to the tail housing, or with a flanged output adapter for a normal four bolt fitting? If the latter, how did you connect the four bolts if the joint was inside the tunnel?

Congrats on the work. The box was only ever fitted by Jag to sixes not V12 a except a handful of special TWR XJRS collaborations. The AJ6/AJ16 engines were slightly different in torque characteristics than the XK but I don't understand the comment about not being suited to sixes when that's all they were fitted to? Probably by BMW as well with different bell pattern?

Pete

Hi Pete,
I posted several pictures of the gearbox conversion here:

viewtopic.php?t=1472&start=10&sid=3883c ... 2fb46e0c57

I've not had much joy locating another DJB bell housing, one was advertised on eBay back in 2011 (http://www.ebay.co.uk/itm/Jaguar-V12-Ge ... 0841970258) The link is very old and no photos. Mine also came off eBay in about 2004 for around 700 quid, complete with the gearbox, new flywheel, new clutch and a clutch cylinder plus an old XJS propshaft which I didn't try to use or convert.

I haven't really looked that hard as I already have one, but I am interested in finding out about it. It seems likely it was offered for kit cars, particularly the Cobra replica with a V12.

The guy who sold it to me said that SNG had something to do with it and I got the rear mount from them a couple of days later(just for the gearbox - not the cross member, which I bought from Stoneleigh years later - mine was missing) . They used to do a conversion using the Getrag, but haven't offered it for some time now. As you can see, the rear mount picks up on the threaded holes at the top of the rear extension casting. The mount was un-drilled below and I just trial fitted, marked the location and drilled myself, then used a completely normal V12 rear cross member, plus the standard manual spring, bolt and rubber cups. The mount proved to be a little long and fouled the tunnel when pushed down - it would have been forever impacting the strengthener under the prop shaft, but was easily trimmed short.



You can see the slave cylinder, I have no idea where it came from, but it looks similar to those I have seen fitted to XJS AJ6 cars, which is where I am told my 'box originated.

Some more shots:

Propshaft:



The prop shaft was custom made, after a trial fit of the rear suspension, engine and gearbox. I measured it and took the measurements in to Bailey Morris in Cambridgeshire who gave a fantastic, quick and reasonably priced service, manufacturing a completely new shaft in about 2 days from ordering.

From beneath:



An early view of the prototype gear lever linkage:



Tunnel Cover:



If I had known there would be as much interest as there has been I would have taken more photos. As to the comment about six cylinder cars, I am just repeating the commonly stated idea that the Getrag is not suited to the XK 6 cylinder engines - I am sure I read it on this forum in one of the many 5-speed debates. It certainly seems to suit the V12.

The installation was not without problem, I had to remove the unit after first engine start as the back face of the clutch plate was fouling the forward end of the tube around the gearbox input shaft, only lightly but enough to cause a squealing noise. Sorry, I took no photos, though I wish I had as it is hard to explain. A small amount of the tube had to be removed. This tube is the assembly along which the clutch release bearing unit slides. When I took the 'box out for this, my initial thought was that the noise was somehow related to the release bearing, so I replaced that too, only to find the one fitted was a very unusual dimension. I eventually modified the bearing carrier to take a more common size of release bearing. However,apart from the modified Auto tunnel cover, there was no modification required to the car metalwork at all. It's a bit of a squeeze but has done a few thousand miles now.

Regards,

My Series 2 FHC has a 5 speed Getrag. I have been told it is a 265. It was fitted during a nut and bolt restoration by a previous owner in the mid 90s and as pete said involved a serious amount of metal fabrication in the tunnel area.
I think a replacement that just slots in is a great idea and would recommend that now but i guess it was not around then.

Curiouser and curiouser. I can't confirm 100% without a measurement but that looks different (significantly shorter) than an XJ40/XJ-S box and unless there was a large chunk sawn off the base, the rear mount area look like a different casting.

265 refers to the main body I think, because both the short box I used in my SWB car and the much longer XJ40 ones were marked 265. So yours could be a 265 of intermediate length. Did it have 'Jaguar' cast in the side anywhere? Jag ones do.

Yes the back of the bell looks like it uses Getrag lever and slave mech and yes the release bearing is a bit wierd. In fact the whole bell looks pure Getrag except for the block mounting flange, so it must have been some kind of 'special', probably moulded from a Getrag bell with an adapter flange fixed to the front face. Very neat and strong.

First gear is a bit low for an XK unless it has a tall diff ratio (in which case it's ideal) but otherwise the ratios aren't bad for a six.