Thread: advice to drain atf via cooler pipes?

Originally Posted by OffTrack

SiddersC the issue is neglected changes rather than age of the transmission. The auto is designed to have the oil changed every 40K km or possibly even 20K Km if you assume the service schedule's arduous usage "transmission oils" category covers the auto. It seems that problems post-change occur when fluids changes are not done regularly.

Haydent, did you do the filter when you did the last fluid change? I'd be very tempted to do the filter again even if you did it last change.

I would say that since the oil was black on the initial change, that the change intervals have been neglected?

Originally Posted by haydent

I did change the filter the first time, I'll do it again as they are cheap. Whether a box is roached or not there is allot off people saying changing old oil all of as sudden is as risk and is say it's likely this happened to me but I do agree I think the box had been cooked at some stage but there where no symptoms till I changed the oil filter for it first time...

The problem is letting the fluid get too old/dirty in the first place. The new fluid contains detergents which can loosen sediments and particles which have the potential to clog the passageways and valves in the auto.

In theory it is possible to overhaul the valve block, and this would be very likely to solve the issue. RAVE actually details removal/refit of the valve block but not overhaul.

From what I can gather on BMW forums it is possible to order all the parts required to do the valve block overhaul. I guess it is just filed under "too hard" for most people.

[ame=http://www.youtube.com/watch?v=iRN1jwEkydg]BMW E32 valve body rebuild - YouTube[/ame]

cheers
Paul

Originally Posted by SiddersC

I would say that since the oil was black on the initial change, that the change intervals have been neglected?

Defintely a good indicator. Problem is that the first most owners of second or third hand D2's know of the lack of servicing is when the fluid is drained.

99% of valve body overhaul is just a clean and make sure that the valves are free. Not sure about ZF's but I have overhauled a lot of the old Borg Warner three speed autos and a few Ford C4's. With the BW auto there are no parts needed for the valve body and the C4 has two rubber balls and from memory a gasket for the two halves.

Anyone who is mechanically minded could easily do this. It is just a case of having a very clean work environment.

Can in get the valve block out with the tranny still in ?

Yes. It's procedure 44.40.01 in RAVE. I've attached the relevant pages.

As I mentioned previously there is a surprising amount of work that can be done on the Auto without dropping the transmission.


BMW used the 4HP22EH on the E28 at least so there is a bit of information floating about on BMW forums and sites.

This isn't necessarily for the 4HP22 but is a useful looking guide to what is involved in overhauling a valve body:
http://www.e38.org/e32/e32%20transmission%20valve.pdf

This pdf contains an article on things to look out for when working on the 4hp22:
http://e28-535i.com/524td/TransTec%2...ZF%204HP22.pdf

Great thanks. I'll definitely follow this up when I've got the dump off to change the filter and oil.

looks easy !

from pdf:

As for my BMW, it has never shifted smoother. My problem of the
transmission not going into reverse and of hard shifts when going from Drive to Fourth
are a thing of the past.