Page 1 of 2

Auto transmission shift linkage

Posted: Tue Nov 19, 2024 3:09 am
by RollyTG
I need some help in regard to how the original transmission shift linkage in my 1965 S-type worked. Does the cable connect to the box from inside the firewall or from outside? My car had been retrofitted with a BW8 transmission and the shift cable is entirely outside of the firewall but I suspect that the original (for the DG250) passed through the side of the transmission tunnel to the shift lever on the side of the box. Could someone who has an early automatic car set me straight on this? The only example I have access to is a manual. Thanks.

Re: Auto transmission shift linkage

Posted: Sat Nov 23, 2024 11:36 pm
by jerry_hoback
I know its been a few days, sorry. My car has the DG250, its gearshift is a bar running next to the steering column through the firewall where it connects to a ball & socket joint at the top of the cable.

Re: Auto transmission shift linkage

Posted: Sun Nov 24, 2024 1:56 pm
by RollyTG
Thanks Jerry. That sounds exactly like what I had with the BW8 setup. The cable went down from the ball joint just a couple of inches outside the firewall and then to the shift lever on the drivers side of the box. It operated the lever horizontally. Is that how yours goes? I have never seen a DG250 so I am in the dark a bit. Would a picture be possible? Thanks.

Re: Auto transmission shift linkage

Posted: Tue Nov 26, 2024 1:18 am
by jerry_hoback
I have not successfully uploaded a picture to this site yet, but lets have a try-
left side of DG250, gear selector arm at right
left side of DG250, gear selector arm at right
IMG_4287.jpeg (2.91 MiB) Viewed 2134 times
At this point I was removing the gearbox to replace the Large oring sealing the front pump. Gear selector is at right.

Re: Auto transmission shift linkage

Posted: Wed Feb 19, 2025 5:17 pm
by RollyTG
Hi Jerry - I am getting back to the issue of my auto transmission linkage. The problem is that mine and yours bear zero resemblance to what is pictured in the Workshop manuals and parts catalogues for S-type or for 420. Maybe someone with greater knowledge than I can shed some light on this because I am mystified. The books all show a linkage and cable that connects to the shifter near the top of the steering column and passes through the firewall on its way to the transmission. Can someone help out here?

Re: Auto transmission shift linkage

Posted: Fri Feb 21, 2025 10:24 pm
by jerry_hoback
For clarification- do you have the DG250 with a different linkage? Do you have a different transmission? I suppose its possible that at this age a later trans could have been swapped in -in any case maybe you could post a pic or a link to a pic of what you are dealing with. Good luck.

Re: Auto transmission shift linkage

Posted: Sat Feb 22, 2025 10:06 am
by cass3958
Rolly the 420 will not look the same as it was fitted with a Model 8 auto box. The S Type was fitted with either the DG250 which is what Jerry has shown or from around Sept 1967 they fitted the BW35 gear box.
I have the BW35 but I have right hand drive so the set up would be different for the DG250 but for the BW35 it should be the same. There is a linkage under the dash which is adjustable but there is a cable that attaches behind the dash and runs through the fire wall down to a lever on the side of the gear box. The set up should be the same for RHD and LHD as it is just a cable with no bars running down the side of the steering column. I checked through my photos and I do not have a photo of the underside of the dash showing the linkage but I have attached a photo similar to Jerrys showing the side of the gear box on the BW35. The wiring block you can see is the immobiliser switch which on the DG250 is under the dash.
Gearbox ID tag.jpg
Gearbox ID tag.jpg (1.18 MiB) Viewed 1303 times

Re: Auto transmission shift linkage

Posted: Mon Feb 24, 2025 2:15 pm
by RollyTG
Thanks Jerry and Cass. Some clarification. My car had been fitted with a BW8 replacing the original DG250. It appears that when that was done a completely different shifter linkage was installed. But it seems to be the same as what Jerry has with his DG250, which in turn is very different from what is shown in the books. The photo shows where the linkage cable connects to the straight shaft which runs alongside the steering column. It comes out through a crudely hacked hole in the firewall. Definitely not standard. The BW8 transmission is out while my engine is being rebuilt. It did work but leaked badly and was deficient in other ways - no cooler, no kickdown in particular. My intention is to replace it with a GM transmission using the kit from John's Cars. That kit is supplied with controls compatible with specific models of classic Jaguars but that will be an issue because I don't have the shifter that the car should have. I don't want to be fabricating a custom linkage to allow the GM transmission to work. That's my dilemma. That and the fact that Jerry's linkage is also apparently non-stock.

Re: Auto transmission shift linkage

Posted: Mon Feb 24, 2025 6:21 pm
by cass3958
Woh that hole is going to let a lot of engine fumes into the cabin and noise.

Re: Auto transmission shift linkage

Posted: Mon Feb 24, 2025 7:00 pm
by RollyTG
True - but that's about the least of the problems at this stage.