My 1999 XKR developed a gearbox fluid leak, from the usual electrical connector on the MB box. So, fully armed with all the necessary information from this forum and the MB forum, I fixed it! - However........ I have no idea how much fluid I lost, so purchased the appropriate (722.6) MB pattern gearbox dipstick on Ebay.
So far so good! - but I'm finding the instructions a bit unclear; I understand that, when hot, the "hot" level is checked when running at idle: but to get it hot, a long-ish drive is needed.
Ok, then I want to make sure I have enough fluid in the box before I start, so I should check the low temperature level............. I guess this should also be done in Park and at idle: - or should it be checked cold and not running at all??
- I did say this was a silly question!

 

Using your purchased dipstick, make sure the level is at the lower mark on the stick, when cold at idle. You should have already run the trans through it's gears one at a time using the gear lever to be sure all circuits are flooded with fluid. As the trans warms up, the fluid level will rise quite a bit. Final level check is done at normal operating temperature, idling, in park.

 

My experience has been that if the level is correct cold, it will be correct at temperature also, but you have to check. One thing to be careful of is the dipstick I bought on ebay wouldn't go all the way through to the bottom of the pan until I filed off the two plastic nubs on the bottom of the dipstick.

 

Thanks for the replies folks, one thing though - I thought that the diamond shape at the top of the plastic section on the dipstick was the stop; do you really take that off and go all the way through?
Cheers,
John

 

Yes, the dipstick has to hit the bottom of the transmission pan. I don't know why they put that diamond on there. Maybe when these transmissions are used in a Mercedes, they use a larger dipstick tube.

Brett

 

No, don't take the diamond shape off, it must stop there indeed as you say! Otherwise you risk a lower oil level then required.

 

According to the jtis (307-01B), the tip of the dipstick must contact the fluid pan. Maybe the actual Jaguar dipstick will pass through the dipstick tube, but the Mercedes tube will not.

Brett

 

I meant to say the Mercedes dipstick will not pass through the Jaguar dipstick tube.

Brett

 

Jaguar is using a different style dipstick, hard to use, the Mercedes version is much easier to bring down.

Its the oil level that is important for the gearbox (the high point must be measured), so you are good using mercedes dipstick with the diamond stop!

 

Thanks for the information folks, I don't feel so bad about being confused now - there seems to be plenty of opportunity to confuse oneself!

Cheers,
John

 

Well, I would really like to get to the bottom of this. If what Avos says is right, then I am running my trans low on fluid.

When I got the dipstick, I had the pan off and I put the dipstick in. It did not protrude out of the dipstick tube. I referenced the JTIS, and this post from another thread by a certified tech, who says you could use a piece of flex cable: Obviously, the flex cable would not have the ears, so it would bottom on the pan. So is there anyone out there who can give a definitive answer?

Brett

 

One more thing I would add to this: On the conductor plate, there is a float that I assume would trigger an error message if the fluid were too low. which mine would be if I was wrong to take off the ears. I do not have that message. But if the fluid were too high, which I think would happen if you used the dipstick as is, there isn't anything to send a warning.

Brett

 

You would have noticed if the oil level would be TO low, you could get sometimes slipping under certain driving conditions, a little low doesn’t have to manifest itself so quickly.

I am not aware of an oil level sensor, and there are no code for that either, so I don't think the unit has one.

Now ask yourself, would Mercedes be wrong with the millions of transmission units out there and their dipstick (the unit in Jaguar is not different, other then maybe different clutches or so)?

 

As much as it pains me to admit it, I was wrong about the dipstick. I have been researching the mb forums, and the dipstick is not supposed to touch the bottom of the pan.

There is only 5mm difference between the bottom of the pan and stopping where the diamond holds the stick, so even with the ears filed off it is still in the range.

So, Frozennorth, you should use the dipstick as you bought it.

As for the fluid level sensor, it is right on top of the conductor plate, as in this photo. In Mercedes, there would be a notice on the dash if the fluid were low. I don't know if jags do this also, but I think they probably do.

 

Thanks for the information, it does seem that there is quite a bit of confusion over this! I have discovered that, with a bit of a push, I can make my Ebay dipstick go past some kind of restriction in the tube, which I originally thought was the stop: - it then travels a good bit further until it stops on something (bottom of the pan or a stop in the tube; I don't know yet). It's enough that the difference in reading goes from nothing on the stick to bang-on midway on the high temperature range after a 15 mile drive...
I've just been looking at the Jaguar workshop manual, which says "insert the dipstick (special tool 307-379) until it stops (tip contact with the fluid pan)"; the illustration in the manual looks very similar to the Ebay dipstick, at least the end and the diamond, temperature levels etc. does - the handle is a bit different.
I think I'll thread something thin enough to get to the pan down the tube and see how far it goes, and compare it to the distance the dipstick goes in; at least I'll be able to figure out how close the dipstick gets to the bottom: at the moment I'm not convinced that it's going as far as it should.
Sealed for life gearbox; who's daft idea was that??

Cheers,
John

 

The information in the Jaguar manual and the uncertainty of the dipstick position is why I filed the diamond off of mine. With the ears filed off, it goes to the bottom of the pan easily and without question.

Since my research on the mercedes forums tells me there is only supposed to be 5mm difference between the dipstick being held by the stop and hitting the bottom of the pan, all I have to do is add 5mm to the marks on the stick for a correct reading.

BTW, right in the middle of the high marks after 15 miles driving sounds perfect.

Brett

 

yep, that's what I found when I probed the tube with a length of wire: there is an obstruction of some kind near the bottom of the tube, but pushing past it with the wire till it reaches the bottom gives a measured length which is about 5mm longer than the dipstick goes when pushed through till it finally stops. I've now marked the point on the dipstick which corresponds with the top of the tube when it's fully home, so should be good from now on. Not that I want to make this a regular occurrence, hopefully there won't be any more leaks!
Thanks for all the help,
John