Transmission leak
 

It has been dripping for some time but recently got a few more extra drops than in the past. Wondering what is the most common leak on the 1997 XJ6L. It is dripping off the pan so could be anything. I just hope it is a pan leak and not a transmission seal leak. Changing the pan gasket is an easy one. Any of the seals......$$$$ I am sure. If that is the case....nothing a good peanut can not take care of.

Pan gasket would be top of the list for sure, but those ZF units are oil tight as a rule.

Seals, doubtful.

Dipstick tube flare nut, had a couple over the years, idiot wrenchers from a previous time usually.

Trans cooler lines, only seen one.

The short tubes om the oil filter housing has o - rings that go bad

https://www.jaguarclassicparts.com/u...-3-2-4-0-litre

The oil dipstick pulls out with a yank with some safety wire . Bolt on the top of the stick . Easy to get on from underneath . 8 or 10 mm ratchet , O - ring on the bottom of tube if I recall not shown in parts pic

https://www.jaguarclassicparts.com/u...-3-2-4-0-litre

Engine coolant from the water rail gasket , under the intake manifold

https://www.jaguarclassicparts.com/u...-3-2-4-0-litre

You have covered the cam cover rear seal area

Um, I think the ask was for Transmission Fluid leaking??????, or have I missed something?????

That is correct...the Transmission. I guess I will try the pan first. Seems to be the easiest to tackle. Just need to find the torque rating on the bolts before I give it a shot. The part number for the gasket would be cool if anyone has it handy. Otherwise, I will look it up

I use aftermarket Trans Service Kits, and they include all that is needed to do a trans filter/fluid change, except the fluid and the labour.

Torque settings, NO idea, just nice and firm, based on common sense, as versus Gorilla tight stupidity.

8 NM or 71 inch pounds ref page 137 of the XJ6 - XJ12 Vehicle Service Manual on the X300 ZF transmission pan

No star Torque pattern given but I recommend

I have considered myself blasting and spraying the pan once off as it looks scary

See also

http://www.jagrepair.com/images/TSB/...ellhousing.pdf

Well, I got it up on the rack and it is not good news....I think....The mechanic said it was a rear transmission seal but at the same time, he found a rear differential leak and a power steering leak. Power steering probably could fix. Everything else I guess I will have to continue to experiment with the mechanics in my area. I am not taking it to Jag unless I win the lotto tonight. I was also told that the rear diff is not an easy job and it is hit and miss with finding the right seals.

Did you look into the differential breather plug being clogged causing heated air pressure in the housing pushing oil past the seals , common

New diff oil rejuvenates the seals up to a point that they don't have to be addressed sometimes

Same with the transmission fluid but no breather plug that I'm aware of

Powerball is $ 281 million tonight

That is yes on both exhaust manifolds PM me on details

So I went underneath to clean the breather plug and noticed that a bolt holding the differential looked like it was not in all the way. So first cleaned the plug and went to feel the bolt and it was hand loose Tighten as much as I could with my hand then went to hit it with a socket. First turn of the wrench and I could tell it was stripped. Got the bolt out. Put in a tap and rethreaded. Took a bolt from my donor car put in the bolt in and got it in a little further before it stripped again. So what next. Loctite another recommendation I think the loose bolt allowed my differential to move and may be the cause of my leak.

It happens in alot of differet applications

Depending on if there is a helicoil in there to begin with that would have to be removed and go a size up

In this application you want the 2 castings to clamp together with a pinch for sealing so the helicoil would have to seat in the intercasting only and not come out to be flush with the outer surface of the plate


If there was a helicoil installed in the first place usually the whole helicoil comes out and the whole thing is on your bolt and not just shavings

You can take a clean bolt to the auto parts store and they have a size mandrel to know what you're dealing with

the stripped off material if still kept would be a clue if it's a soft metal like a naked casting metal or a stainless steal material of a helicoil

I have not put one in in this differential but there should be a max torque value so this doesn't happen and will look for it in the Jaguar documents

An example of a repair kit at Home Depot ( not the specific size ) in the below link before the video

https://www.homedepot.com/p/E-Z-LOK-E-Z-Coil-Thread-Repair-Kit-Standard-4-40-tpi-17-in-Installed-Length-SK20215/304617854? cm_mmc=Shopping%7CG%7CBase%7CD25H%7CMulti%7CNA%7CP LA%7c71700000032394431%7c58700003837562549%7c92700 030712663209&gclid=EAIaIQobChMI3Jy3m8-z3wIVyrrACh0qbQy_EAQYAyABEgLyuvD_BwE&gclsrc=aw.ds :icon_dance-disco:

and

https://cimg2.ibsrv.net/gimg/www.jag...f75e6ee355.png

Original document torque value of X on page 183 of Jaguar JJM 1004 12 / 50

trying to link it to you but is to large a file / maybe this link will work for you

https://www.carmanualsonline.info/ja...orkshop-manual :icon_dance-disco:

This may have changed in a later TSB

Here is one for your ZF 4HP24 transmission :

https://www.scribd.com/document/3477...ertrain-zf-pdf :icon_dance-disco:

I have a transmission part # list on my laptop for your rear seal if needed

SO let me see if I understand how this works. So it is an M20 bolt. I put one of these in and then go a size smaller? The bolt I pulled off the donor is fine. I used a tap already and it goes in fine but when I put the bolt in it is a little loose. So I would put that in and then go a size smaller.


After seeing the video I think I get it. But since I really can't see the hole due to the frame not sure I want to go that route. Either that or let someone else try it. Not sure I feel comfortable with the process.

So I did a little more research and was going to give it a try but it appears that the kit for this bolt is hard to come by and I found two 0ne at $100 and another at $256. Looks like the companies know what they have here. M20 X 1.25

Hi cdma, there is a breather for the auto transmission and it's right at the back on the top and will blow out a bit of fluid especially if you overfill it, you can guess how I know that, and it can look like a failed output seal, its very hard to see even under the car, it looks like a while plastic nut, it's normal to get some residue around this.

Hi Phil,

I'm curious to know which bolt on your differential is stripped. If the size is M20 or similar, that sounds like the fill plug. I can't think of any other bolts on the diff that would be anywhere near that large on their threaded shafts. If it's the fill plug, then it's probably a tapered pipe thread (e.g. NPT), not a metric thread. In that case, it doesn't need to be torqued very high and some thread sealant on the threads may be all you need to make it seal well enough. If its one of the diff mounting bolts, you may be able to tap the hole for the next larger bolt (the next larger SAE/Imperial bolt may require the least enlargement of the hole and therefore the least risk of creating an even bigger problem).

Could you possibly post photos of the bolt and the spot on the differential where it threads in?

Cheers,

Don

If you look at the picture you will see a bolt that does not look seated all the way. That is the bolt. It holds the diff to the frame.

Here is the picture. Not sure why it did not post

https://cimg2.ibsrv.net/gimg/www.jag...3b53662e16.png


I'm seeing it as the center one in the pic as the one cleaned of the grease

May be only the subframe plate has to be removed to put a helicoil into it

This makes it a structural load bolt

Rear mounting bracket to differential bolt torque of 85 - 105 NM ref page 183 for the original bolt size

This would have to be double checked by someone else

The helicoil chosen does not have to match the metric size and pitch of the original but maybe a more common and cheaper even English as long as it's a course thread

https://www.jaguarclassicparts.com/u...e-carrier-rear

The good news is you have a good angle on it

Hi Phil,

I'm certain those screws do not have M20 shafts, and I don't recall them having M20 heads either. Try a 19mm socket on the head and see if it fits securely. My guess is that the threaded shaft is 10mm standard pitch (1.50). If I recall correctly, the pair of more rearward bolts are fine thread (1.25?).

I don't think you would need to remove the subframe to install a helicoil, but assuming those screws are 10mm, another option would be to tap the hole for a new 7/16-14 or 7/16-20 screw. 10 mm equals 0.394 inches; 7/16 is just a little larger at 0.4375 inches; and 12 mm is even larger at 0.472 inches.

I'm away from my reference library and laptop so I can't tell you the torque spec for those screws but I'll try to check when we get back home.

Cheers,

Don