I already know to drop the pan and drain the torque converter. But, how to best open up the fluid circuit to completely drain all the fluid before a fill? I prefer not to do a pressure flush. Is it possible to also open the line at some point and gravity will finish a fluid drain? Thanks

Mike
1986.5 with auto trans

 

Unless your fluid has been contaminated by major transmission failure, the amount left in the lines will be inconsequential.

 

If you drain the pan and converter..the lines gravity drain already...

 

well since your not asking about the torque converter,
you should know that the TC has a drain plug on it ,
and its removed through the grate at the bottom of the transmission,

its best to have a helper spot this drain plug as someone else slowly turns the crankshaft,
once the drain plug is removed you can count on about 5 QTS coming out of the TC
you should have 10 QTS on hand for the refill and to top up your powersteering

 

You can disconnect the hose which goes to the front of the car, on the right side, and blow air through the line, if you are really concerned. (Before you plug up the converter and the oil pan.)
This will push all of the fluid out of the front cooler and the lines.
(If the fluid isn't burned or crazy dirty, this is not generally required.)

 

Everyone; from my experience with filling the transmission case after servicing:
don’t use the filler bowl for fluid filling purposes. The transmission filler bowl is close in proximity to an exhaust that gets hotter as the filling progresses (the engine is running at least during the top-off part). Connect a fluid pump Tube to the nipple At the lower Passenger side front of the transmission. Just unscrew the cap on the Nipple and press the pump’s tube well onto the nipple. Then just pump the fluid in, while watching the filler bowl level. Some pumps attach directly to quart or gallon bottles.

 

Just was going through some forums to try and find one that was closest. I am going to service the auto trans on both my 1987 S4 and 1986.5 S2, Very similar boxes obviously but there seems to be no pictorial or video step by step that i can find. I want to do the torque converter, box and rear final drive and know that I can do all these whilst im in there. Both of these have been sitting for over 10 years so I need to tick the box on both of these. Neither is leaking and Roger has sent kits out to me. to do the job. I want to do these on my own as opposed to having to rely on very limited resources here in the South Island of NZ. I have access to our workshop and hoists at work here and will be having help from my usual mechanic who is a total euro nerd and loves this kind of stuff, Can anyone point me in the direction of a good tutorial ( pictorial or video ) that I have missed that is useful please ?. Ive got the workshop manual but it seems a bit vague...unless it really is simple and im trying to over complicate things??? Lastly, I get a slight clunk when going from forward to reverse and vice versa, Ive been reading the forums from ages ago that suggest the torque converter plate is held together with rivets that Porsche say should be replaced with bolts as they wear. My S4 has 127000 kms and the S2 has 178000 kms so im thinking this might be worth checking. So is this something that's easy to check like the front flex plate ?...ii would be nice to achieve this whilst its up on the hoist doing the trans service with out taking everything apart, can anyone enlighten me as to where this might have been covered as Ive been searching for that too. I appreciate it would be easier done if everything was being taken apart but im trying to avoid it. Cheers. AL

 

Oilystair,
whereabouts in southern NZ are you?
Changing the fluid in the auto box is reasonably straight forward, slightly more complicate if you replace the filter at the same time (recommended). A new sump gasket will be required also.
Changing the diif oil is also relatively easy. The critical thing is to loosen the FILL bung before draining the oil out. (Some have been caught by not being able to undo the fill bung after emptying the diff).
The clunk could be the rear half shafts. Often the boots are torn and they could do with repacking. Swapping side to side can help extend life once the maintenance has been completed. Trick here is to make sure the bolts onto the diff are tight or are physically restrained from backing out.
The flex plate ( at the rear of the engine) is held on by rivets. These often cause a rattling sound if loose and can be replaced by bolts.
The rear driveshaft clamp could also be loose and should be checked periodically. A new bolt should be used.

Myles

 

Hi Myles,

Its nice to see another South Islander !!!, Im in Nelson and am lucky enough to work for our Lexus / Toyota agency who also own Mag & Turbo here, so we have some excellent resources and knowledge...but some of it is so specific on the 928. One of our guys is a BMW, and Mercedes specialist, especially older stuff so he is super useful...but he just left :-( I have a auto service kit for both of mine from Roger Tyson at 928srus who I currently get all my bits from and that includes, filter, gasket and crush rings, so im all sorted on that front. I see youre in Cromwell which will no doubt mean the guys at Autothority ( who really know their 928 stuff ) will be looking after you but its a bit far for me, especially as my 928s is non running at moment..Il try to pool my resources here and see how I get on, I reckon im over thinking it. Good advice re the drive shafts and everything else. I should give you a call as it would be nice to speak to another person with one who is at least in the same country !. Cheers. AL

 

AL,
never dealt with Autothority as they are a very quick 3 1/2 hrs away (5hrs legally).
I tend to do 90% of my own work and deal with Roger a lot, but have also used the other providers in the USA.
Most of the jobs are easily accomplished with a bit of care and some basic tools. Torque wrenches are probably the most specialised to deal with the tasks above.
Will PM you a contact.

Myles

 

You should find most of what you need on Tony's site. His transmission fluid change page is here: https://members.rennlist.com/v1uhoh/transmis.htm

If you scroll down his main page (near the bottom), you'll find "Routine Checks and Maintenance" and "Non-Routine Checks and Maintenance - bigger stuff" drop down menus: https://members.rennlist.com/v1uhoh/