I am in the process of restoring my S Type. Shell is stripped and engine out. I have no idea of the condition of the DG250 autobox, apart from the fact that it drove into my shed under its own power, and was last on the road in 2014 I think. Oh and it's leaking fluid!
I would like to have it refurbished before refitting but cannot find anybody here in Ireland who will do it. There is a very good transmission specialist very near me who I have spoken to. He says that DG250 parts are just not available if he finds anything that needs to be replaced, but there is a company in the UK that will refurbish it, but they won't supply parts to anyone else. The cost of this is however prohibitive for me. If I had a BW35 my local guy would be happy to take on the refurb and the cost would be manageable. In fact a look on the interweb reveals many rebuilt BW35's available at a reasonable cost...although I have found none specifically for a 3.4 S Type.
My question is can I fit a BW35 to my S Type? Is it a straight swap?

 

don't know about the BW35 but if a BW66 can be adapted to a XK engine, chances are the BW35 can be too.

In the US there are a number of DG250 rebuilders and some parts suppliers. Search for "DG250 USA" in any search engine. or try "Detroit Gear transmission"

The DG250 was used in 1950's to 1960's Studebakers and then Jaguars started using them. It is a pretty reliable transmission though it leaks when they are 50 years old. But what doesn't? Try new gaskets.

my S type has one and it shifts fine. It also has the "Second Gear Hold" which works well in slow traffic. Just don't forget to turn it OFF after 30 mph.

 

I would go for the BW66 from a Series III XJ6 if you can. Certainly the gear changes will be smoother. GW Whitehouse makes a conversion using the 4 speed ZF 4HP22, but it's a very expensive conversion. They can rebuild your DG250, but again probably not cheap. No automatic rebuild is cheap, simply due to the labour involved. It's not a terribly complicated transmission if you have time and want to try a DIY rebuild.

 

The BW35 will go in to the 3.4s as I have it but it is standard on my S Type being a Sept 67 car.
The differences between the DG250 and BW35 are the inhibitor switch is on the side of the gearbox whereas on the DG it is under the dash. Simple matter of extending the wiring.
On my BW35 there is no speed hold.
On the BW35 there is an oil cooler that runs two pipes from the right side of the gearbox to an oil cooler in the bottom of the radiator. Not sure that the DG250 has got this. You can plug the holes and remove the pipes so the cooler is not required.
I am not entirely sure but I think the kick down mechanism is different. The BW35 uses a cable for the kickdown and the DG250 has a set of solid rods. Please correct me if I am wrong.

Fitting the BW66 has been done but as far as I am aware the BW66 was a floor change not a column change so that has to be taken into consideration.

Personally I would have the DG250 repaired with new seals and the leaks will go away (all 50 year old gearboxes will leak) and you do not have to make lots of alterations to make another gearbox fit.

 

A BW35 would be nice but there are column & linkage changes required & a Bowden cable IIRC. Certainly doable.

From a highly respected member of the S Type Register, Orlando.

"All DG250s leak, unless they have been sealed by a specialist. They leak particularly after standing a while, because the ATF drains out of the torque convertor and raises the level in the gearbox to the point where it is above things that were never sealed - eg speedo drive. You'll know if it's ATF leaking because it is red.

Secondly, the DG box has a rough change from Low (1) to Intermediate (2) and a very smooth change from Intermediate (2) to Direct (3). It's just how they are. My wife laughed at that too, but you get used to it. And, if you're gentle on the throttle, it's not so bad.

The world authority on these boxes is Graham Whitehouse at GW Autos of Halesowen, England and if you call him, he will happily give you chapter and verse on why they are how they are. He will recondition the box happily."



GUV 807C is Orlando's DG250 fitted car. They did his transmission rebuild.

 

Cass no oil cooler in the S type, DG250 is not as smooth as the BW66 but it moves the car from point A to point B. It is after all, a primitive 1950's design.

I actually like it. Having both a 1965 S type and a 1984 XJ-6, I do prefer the 3rd gear of the DG250 because it performs almost like a 4th gear. The 3rd gear of the BW66 keeps the rpm's of the 4.2 engine higher than the 3rd gear of the 3.8 engine at highway speeds.

So the gearing must be different? I have no clue.

A firm in Texas called John's Cars sells a kit to fit a 4-speed GM 700r auto transmission which are abundant and cheap in USA salvage yards. It fits 3.4, 3.8, and 4.2 engines. Lots of MK-2, MK-X, 420, and XJ-6 have these installed.

the problem for me is that I am not a rocket scientist and with any conversion a good number of issues have to be resolved and dealt with before you have a smooth running classic car.


.

 

There was a thread on the install of one of these kits recently on the XJS forum. I was surprised at how far from a bolt in it is, and after seeing the photos of the modifications the person had to do, I would not want to install one. The GM transmission is far from trouble free too, depending on the amount of power you want to put through them. Get the TV cable adjustment wrong and the transmission will be completely burned up in 3 miles.

OP is in the UK, so a 700R4 would be a rare thing. I'm in Canada and most of the cars that would have had a 700R4 are gone, long since rusted and crushed. Production usage ceased 30 years ago, so they are not very common anymore.

 

Sorry Jose there is an oil cooler. It is not for the engine though it is to cool the gearbox oil on the BW35. There are two pipes that run from the right side of the gearbox to the bottom of the radiator. The radiator is split with the water cooler at the top 7/8 and the bottom 1/8 is a cooler for the gearbox. They were only fitted for the BW35 so you will not find it on the DG250 cars.


These are the cooler pipes coming out of the right side of the gearbox on the BW35.

This shows my engine ready to be fitted with the gearbox attached and the copper pipes can clearly be seen running from the gearbox to where they would attached to the bottom of the radiator.

This is the bottom of the radiator with the water outlet to the right and the two pipes to its left which are for the gearbox cooler in the base of the radiator.

 

that is what I mean Cass, no oil cooler in the DG250.

 

Thanks for the responses.. I am in Eire not the UK so any work by a specialist in the UK will involve shipping or delivery of the unit. I have had a response from one company in the UK so far, Borg Warner Specialist, in Leeds;

The Borg Warner Model DG transmissions are one of the earliest automatic transmissions, and they are much more complex than the BW35. Parts are more expensive and labour hours are significantly more involved pushing up costs. Our standard cost for a BW Model DG recondition is approx £2,600 if there is no major hard parts failure. If there is further problems and hard parts need replacing this could add approx £500. In most cases, it’s just friction material that fails, which can be picked up in the standard recondition cost of £2,600. The Jaguar S Type did fit the BW35 in later models, therefore it is possible to fit this gearbox in your vehicle. The cost to recondition a BW35 is £495, significantly less than the model DG. Now changing from your DG to a 35 will not be straight forward. You will need to make modifications for; gearbox mount, selector mechanism, throttle linkage / kickdown cable mechanism and propshaft. We do have the parts available to make this swap. This includes, BW35 S Type Gearbox, Converter, Bell-housing and kickdown cable. You will have to make the other modifications yourself. We will require your DG gearbox and converter in exchange to avoid a surcharge.

 

right, there nust be a reason they want your DG250, they can probably sell it for a lot of dinero.

 

Ouch! I would still speak to Graham Whitehouse but while scribes vary on date. Taylor says "during 66 & others say in September 1967 Ambla replaced leather in the [S Type] interior along with cheaper carpets and the Borg Warner Type 35 supplanted the DG as the automatic transmission".

I would be looking for an ultra cheap bashed up or rusted donor car with a BW 35 fitted so you can just move the entire column & linkages/cables, mounts & propshaft across to your car & have the BW 35 reconditioned.

I ended up with 2 donor S Types (one incomplete) & a Mk2 shell as a package deal for peanuts. The sale of one IRS to a kit car guy more than covered my expenditure on the whole lot.

 

compare prices with Charlie Tranny

https://www.charlietranny.com/Automa...for%20Sale.htm

 

Graham Whitehouse will not be cheap, but his work is excellent.

Though I prefer a 6 (or more) speed ZF over any manual or automatic, for the sort of auto boxes that can reasonably be fitted to our cars, I'd go for a manual. And if my left leg wasn't up to operating the clutch, I'd fit a servo.

 

sorry ~ wrong thread! Provided by PM.