P38A Gearbox question

Hello all,
I haven't been on for a while, seems that the old girl is behaving well at the moment (shouldn't have said that...)
I have a question regarding the gearbox. I have been trying to check the level of fluid in it but I cannot get a good reading no matter what I do.
I have just had to make a trip to Cornwall for a funeral and went to check all levels, as you do! I firstly just tried the dipstick without the engine running and there was nothing on the end of it. I then did the normal check as per the book, no matter how many times I tried the fluid was about 7 inches above the full mark. Stopped the engine again and checked and again no fluid showing. The fluid on the stick when running is still as pink as the day it went in about 9 months ago so no burning is present. The box works fine with no warnings, it works fine in sport mode. I have just done the round trip and accumulated 300 miles trouble free (including the EAS, which is a miracle on its own) The oil is still pink and the tranny worked flawlessly so I am at a loss as to the inability to get a good reading as there is obviously fluid in there. The one thing I always had since I have owned the car (5 years) was fluid escaping from the filler, I put tape on the dipstick a few years back which stopped it (I had a minor fire from the oil dripping on the manifold) Any ideas, as I mentioned, all functions fine and the fluid is pink.
The old girl is a 97 4.6 Gems HSE
Cheers

Sounds like it's overfilled.

Most boxes with dipsticks have a cold and hot mark, what does yours have?

I presume you have the correct dipstick for your box.

Ideal test is hot, (40 deg) run gears slowly through PRND321 and back before checking dipstick, clean it first then dip.

It does have a hot and cold mark, which makes it more strange that there is no fluid showing when cold, I would have thought that if it was overfilled it would at least show on the lower line. It is the original dipstick and when I did the check as per the "book" it was up to temperature and I cycled through the gears as you have mentioned. A bit of a strange one I think, if it was really low I would have thought I would have had issues by now and the fluid would be burnt and the box would over heat.

The book RAVE, for the GEMS, says check it cold! The marks on the stick are Max and Min- not hot and cold.

NOTE: Check the fluid level only when the
engine and gearbox are cold.
1. Ensure vehicle is level, then select ’P’ (park) and
start the engine.
2. With the engine running at idle speed and both
footbrake and hand brake applied, move the
selector lever to position ’1’ and then back to
position ’P’.
3. Still with the engine running remove dipstick,
wipe using lint free cloth.
4. Reinsert the dipstick fully and withdraw again to
check the level.
5. Check fluid level registers between MAX and
MIN marking on dipstick. For fluid
recommendations. See LUBRICANTS, FLUIDS
AND CAPACITIES, Information.

Hi Orange,
I have done the above with the same outcome, with engine off no fluid registers, when checking by the above process the fluid is halfway up the dipstick about 7 inches above the max mark. It is as clean as a whistle I am baffled, I am wondering if the box is pressurising and blowing the fluid up the fill tube? The fluid line that is showing is not very visible though, Everything works fine with the box.

Cheers anyway

Misinformation kinda does work,
thanks Orange for providing the correct info.

Cornish, as I read it you must start the engine from cold, also cold gearbox, move gear lever through the gears slowly a couple of times, put it in park,(engine still running) then get out, pull the dipstick, wipe clean and re-insert, now remove it to give you your true reading, halfway between the low and high marks is the ideal level.

If you did this and it's still high then I'd remove some oil.

cornishboater said:

Hi Orange,
I have done the above with the same outcome, with engine off no fluid registers, when checking by the above process the fluid is halfway up the dipstick about 7 inches above the max mark. It is as clean as a whistle I am baffled, I am wondering if the box is pressurising and blowing the fluid up the fill tube? The fluid line that is showing is not very visible though, Everything works fine with the box.

Cheers anyway

Click to expand...

they are difficult to check level once egines run as oil does splash up the tube you need to wait awhile and dip several times to get a decent reading on the stick

This is actually quite annoying that gearbox dipsticks are not accurate. I definitely have overfilled mine slightly it has not made any difference to how it drives. I suggest you put 1/4 l in then drive for a few days then recheck. With the car running and cold you want a fill to the mark or halfway(when level)

Sorry just re read your post. Don't put any more in! It's easy to drop some out to. Remove the Allen bolt and catch oil with a container . Removed enough then finger over hole work bolt back in you will get a bit of atf on you but the holes small so easy. If there's a bit to much in it'll be fine way to much don't know probably spurt out the breather if it gets hot when towing.

Cornishboat- you say right at the top:
"The one thing I always had since I have owned the car (5 years) was fluid escaping from the filler, I put tape on the dipstick a few years back which stopped it".
If you've never changed the fluid or had to top it up or anything, I'd say that your problem above was actually related to the gearbox being overfull ever since you've had it!
At 7" above max on the stick (when checked according to RAVE procs) I'd say that it's still very overfull.
After 5 years a partial fluid change will probably be beneficial. In theory you'll get around 4L changed.
My suggestion- drain it, refill with new DEX 3 to halfway between min and max mark- measured according to the RAVE process I've shown above.
Out of interest, compare what quantity you've had to put in with what you've drained out.

I had the transmission filter changed about 3 years ago and as far as I know the correct amount was put back in. As a matter of interest has anyone tested their level with the engine off? It just seems strange that if it is showing overfull with the RAVE process that there would be no sign at the tip when not running....
I shall probably take the advice re draining and refilling, it aint going to hurt it
Where does the breather end up, maybe it is blocked somewhere?

Don't fixate on reading it with the engine off, the procedure for the box is with the engine running, and therefore the gbox pump running and the galleries filling, and the non returns working, it's not necessarily like an engine where you can read it with engine off.

If the oil was changed by someone else and they put in the correct amount for an empty box then I suspect is over full. When you drain it you only get about half the oil out