On my 1966 3.8 S I'm looking at a John's Cars switch to the 700R4 transmission. As it sits the car's DG250 leaks like mad, the inter. speed hold is toast and I don't even know if the transmission is good at all. Considering the cost of the solenoid and the R/R of the part and these other factors the swap looks good, BUT. . . the car has AC and one more cooling coil in front of the condenser and the radiator won't help. So electric fans? Oh, wait now I need more juice than I think the generator is up to. So an alternator? Oh, poop there goes the power steering pump . . . how about a junkyard Prius EPS? MORE juice . . . And please keep in mind that I ain't rich and to me, this car might be beginning to resemble a DeLorean.

 

Wonder if you can do a 4L60E. Gets rid of the cable.

 

actually want to install a floor mounted shifter ie Lokar

 

The intermediate speed hold is probably just the belows that have failed, its easy to change and can be done with the box in situ. When they go fluid just pours out uncontrolably.

Personally I like the DG250 and unless you really want to change it or use the car a lot I would just reseal it all (new seals, bellows and gaskets), they do always leak a little but mine has had new seals and gaskets and it doesn't drop any more than a car of its age should, the one in my last 3.8 S-Type had failed belows and leaked like the Exon Valdez until I changed it.

 

I've considered that and so had the PO which is why the ISH solenoid was trashed and the terminal end was hammered out and bogded with silicon to forever stop the leak. I'm hoping that the pool of ATF is from a crapped out pan gasket. Homer, any comments on this solenoid? A Youtube video and some posts show it works for a while then leaks appear again. Also the tail piece of the DG must be removed to install. I'm not committed to the mods, in fact, I prefer stock even if it's antiquated. That's the point of having an old car, isn't it? However, I will be replacing the dinky electric fan that the aftermarket AC installers put in, with a high CFM/low amp modern one.

https://www.sngbarratt.com/us/?gclid....8%20%26%20340

 

Im afraid I've only ever used the original solenoid which have always seemed to work well and not leak (once new belows are fitted).

I would jetwash the transmission, let it dry and then run the car for a short test drive and see if you can find the leak.

if it's a huge amount then I would think bellows (or the bodged silicon on the solenoid), the seal on the torque converter, the output shaft seal or the oil pan in that order would be prime suspects.

I do have the original manual for these if you need any pages copying, I used it to rebuild mine and it was great.

best of luck.

 

thanks will bookmark the post

 

I have a MK-1 with 3.8 and the good ol B&W three speed It works great, the whole car has been rarely use for decades other than to drive around the block every so often, I'd like to upgrade the AT to a OD box, maybe even a 5 speed od. the question is: what is easiest as far as screwing onto the engine--the rest is just metal~~Did Jaguar ever upgrade?

Cheers;
Michael

 

https://www.johnscars.com/mark/markqb.html

no upgrade as far as i know, this is also the only reputable kit

 

with John's Cars kit you will need a different Starter too.

I know of a complete DG250 for $800. plus shipping. (assuming it has not been sold).

Also I have an XJ-6 Series 2 center console shifter assembly wirh cable, as well as an S type center console Panel with the oval hole for a manual transmission shifter, if you decide to go with John's Cars kit.

If it was me, I would repair what needs repair.