Porsche Enthusiasts Club Forum

When my transmission is cold the changes are fairly harsh. (mmmmmmmmmmmmTHUDmmmmmmmmmmTHUDmmmmmmmmmmmm)

As soon as the car has been driven a mile or so it becomes just a slur into the next gear, like any auto box.

I've tried full throttle changes (only when fully warmed up of course) and everything is fine there. The previous owner says he recently changed the transmission fluid, and it does look nice and red, and to level.

Could this be something to do with the vacuum modulator? (taking time for the pressure to build up in the vacuum system) Or is the auto box worn.

Hi

Almost always that sharp change problem is caused by LOW AUTO FLUID...

It is an absolute pig to check CORRECTLY....I.E..engine HOT ,put lever through all shifts TWICE (with foot on brake)... all 4 wheels LEVEL then check with engine RUNNING...

Get it checked and I would bet you have low fluid....and if you think checking it is bad, then filling is even worse lol

All the best Brett

Lovely.....I'll get onto that this weekend. I assume it's just regular AT fluid.

Only one other question. Should I do this before or after the worn front shocks, loose electric window, intermittent heater fan, faulty headlamp relay, noisy wheel bearing, leaking condenser, jammed door handle, and inoperative volt meter?

Hi

Loll...well all 928 owners have their "lists" lol....

But the change should be high on it....

All the best Brett

I don't mind the list of snags. I like working on cars. I got fed up with my BMW Z3 2.8 because there was nothing needed doing on it.
How much oil does the transmission hold? Can I not just add some. Say a half litre? The level is half way up the plastic reservoir when the car is sat in the garage stone cold.

Hi

The auto tranny holds 8 ltrs but IF you change the fluid you will only get 6 ltrs in...

You COULD just add some but the excess will blow out....and its not exactly accurate lol..

All the best Brett

Hey Lightning ... I had a 2.8 Z3 as well (in red). Engine dumped the oil out of the air intake one morning though so we fell out!
Regards
Paul

What type of fluid should I use in the auto transmission? I don't know what is in there at the moment, except that the previous owner claimed to have changed it this year.
I have some Renault AT fluid, it says AT2 on the container (which I assume means it is "Dexron 2"). I went to the local motor spares but they offered me "Dexron 2" and "Dexron 3".
Can I put either in? Are they compatible, like DOT 3 and DOT 4 brake fluid?

STOP PRESS...I've just been informed by the previous owner that it was Dexron 2. So I have to use the same for topping up then?

Reversed the car on to some ramps this morning, as my drive is on a slope this meant the car ended up level. Had a look at the transmission and fluid level in resevoir was on "MAX".
Started engine and shifted into gears a couple of times, then back into Park, left engine running and had another look. Level was right down to the bottom of the resevoir tank. Took nearly a litre to bring it up to the "MIN" level on the resevoir.
Put cap back on resevoir and changed gear a few more times. Level ended up just above "MIN" level (with engine running) With engine off the resevoir fills up to the top.
I imagine if you stopped the engine with the cap off after filling it, you would lose a fair bit of fluid.

Hi lightning,

How is the gear change now that you've topped it up ?

The transmission is better. It was always OK when warm, but is now OK when cold too. There also used to be what felt like a bit of slip on the 3-4 change, and this has gone away as well. Also sometimes when changing from 2-3 there was a bit of a judder. That has also cleared up.
The advice about transmission oil level being critical is clearly true.

looks like i need to find some way of getting mine off the ground and level then, think it has most of the problems you had

Hi

You see....sometimes I do actually know what I am talking about...lol


All the best Brett