two ZF 4HP22 repairs

[winfred]

i took a few pics of core tranny parts to give a strong idea on how to repare this common defect, this tranny is in m20 bimmers, m30 bimmers after about 84, volvo 740 without overdrive non turbo, peugot and jag don't know which. this is how to repare the main problem with the tranny, when the car will only move in reverse and in extream cases not move at all.

this is the cause of the problem, these steel seals leak and send pressure to the 1st gear clutch pack and burn it up
http://members.cox.net/wdixon27/tranny/seals
these are the bolts to take out to remove the bellhousing and pump as a unit, unless you need to replace the converter bushing you do not need to take the pump apart or off of the bellhousing (i will describe the proceedure for that and why at the end of the post)
http://members.cox.net/wdixon27/tranny/bellh%20bolts
heres the bh/pump assy off
http://members.cox.net/wdixon27/tranny/bell%20pump
heres the front of the rest of the tranny and case
http://members.cox.net/wdixon27/tranny/front%20of%20tranny
grab the a-clutch basket and yank it out of the bh/pump assy
http://members.cox.net/wdixon27/tranny/aclutch
heres the back side of the a-clutch basket, theres a steel bearing surface missing in this pic that you will have, between all rotating parts theres a bearing race (looks like a washer) flat roller bearing and another race
http://members.cox.net/wdixon27/tranny/back%20of%20aclutch
you can leave the shaft in a-clutch basket or pop it out so the basket will sit flat on a bench, of you can just leave the whole thing in the bh/pump assy while you do the clutches. theres a spring clip that holds the basket together that you remove with a screwdriver or pick
http://members.cox.net/wdixon27/tranny/spring%20clip
inspect the basket for cracks, i've found a few blown up from people who didn't take no for a answer, also look at the grove the spring clip was in, those ears can break
http://members.cox.net/wdixon27/tranny/abasket
heres the pack of disks and plates, theres a black wavy disk on the top and bottom of the pack that you reuse
http://members.cox.net/wdixon27/tranny/aclutches
this pressure plate is under all of the clutches, you can see some of the burnt clutch on it, clean that off and clean under it
http://members.cox.net/wdixon27/tranny/pressureplate
heres a new disc and steel, soak the discs in fresh atf a few minutes before installing
http://members.cox.net/wdixon27/tranny/clutchpplate
with the teflon seals there should be a drill bit and a sandpaper flap drill thingie, i've never drilled the hole in the 25-30 trannys i've done, it's up to you, it's to releve any future leak pressure, i've been doing these for over 5 years and have yet to have one of my repares fail. the sandpaper drill thingie is used to knock down any burrs left from the steel seals here
http://members.cox.net/wdixon27/tranny/pump%20bore
seals
http://members.cox.net/wdixon27/tranny/teflon%20seals
and where they go
http://members.cox.net/wdixon27/tranny/seals
after cleaning the bore from honing it, stick the input shaft back in the a-clutch basket (if you removed it) lube the seals and bore with atf, make sure the three pieces of the bearing are inplace and slide the a-clutch assy back into the bh/pump assy, it will seat with a thunk and spin freely
put this bearing race on the of the input shaft/a-clutch assy, then the bearing and last the other race, it will be the smallest of all the races
http://members.cox.net/wdixon27/tranny/bearing%20cap
then insert this gear into the a-clutch assy
http://members.cox.net/wdixon27/tranny/gear
till it's bottomed out in the clutch pack
http://members.cox.net/wdixon27/tranny/gear%20installed.
if you didn't break the paper gasket that seals the pump to the tranny you can reuse it, a new one is a bitch to fit onto the pump without ripping it, all that's left is to reinstall the bh/pump assy into the tranny, get comfy this can be fun sometimes, what the object is is to slip the fingers on the back of the a-clutch into the slots of the 2nd gear clutches in the tranny case, twisting the input shaft helps you gotta feal your way in, there will be no gap between the pump and tranny case when seated, tighten the 17mm bolts in a cross pattern, and you are done.
take your time, look carefuly at how everything came apart, if in doubt dump atf all over it if it's inside of the tranny, the bently manual has a exploded view of the tranny if i remember right, when installing the converter make sure it's all the way in, if the tranny and motor won't go together find out why, don't pull it together with the bolts, you can destroy the pump and converter.

i get most of my parts from these guys, but theres almost always a tranny parts place or two in town
http://members.cox.net/wdixon27/tranny/atc%20book

new problem
the converter seal is leaking you just replaced it and it's leaking again, the bushing behind the seal has walked forward and is blocking the drain, time for a new bushing
http://members.cox.net/wdixon27/tranny/bushing
it's hiding here
http://members.cox.net/wdixon27/tranny/pump%20bushing
take the bellhousing pump assy off as seen in the a-clutch repair and take the rest of the bolts out of it and separate the pump from the bell housing and take the bolts out of the back of the pump, then you can strip the pump all the way down and press the new bushing in, reassebly is covered in the a-clutch repair

[winfred]

god i need a beer after all that! somebody grab this and host it for the board please, it may be useful

[warton]

i took a few pics of core tranny parts to give a strong idea on how to repare this common defect, this tranny is in m20 bimmers, m30 bimmers after about 84, volvo 740 without overdrive non turbo, peugot and jag don't know which. this is how to repare the main problem with the tranny, when the car will only move in reverse and in extream cases not move at all.


Though I will never attempt any tranny repair in my life (okay, MAYBE a clutch if I ever get a manual again), that doesn't stop from appreciating your post! Thanks for your efforts.

Oh, and enjoy that beer. ;-)
Peter

[George M]

ever read on the board. Hats off! Excellent review of a common and expensive failure for ZF autobox owners like me. As to drilling the little relief hole...I am right with you. Best to not drill the hole. No less an expert than Kirt Koeller does not drill a relief hole in any of these transmissions he rebuilds either and he does a lot of them.
A question...if I were to run into this failure...do you now take on these repairs from forum members? Is so, what would be your price less shipping
for a standard rebuild of clutches and seals?
Many Thanks for your contribution Winfred...really good stuff.
George
90 735iL/149k...original ZF 4HP 22EH that still shifts like new..but for how
long?

[sbcncsu]

Great job Winfred!!! Kudos to you!

Transmissions are just mechanical things. If you are new, looking at the insides of a transmission for the first time, it looks foreign and undaunting. But, when you have seen their inards and begin to understand how and why they work, they are no longer as difficult as they seemed at first. This repair I would liken to the 4L30E Intermediate Housing Gasket Failure repair. In that repair, you remove the bell housing, pump and all, the overdrive housing and there the gaskets are. They are easy to get to. From my experience the 4L30E is a great, strong transmission, the hard parts in mine were perfect, heck even the clutches were nice and thick and not glazed at all!


And I see you get your parts from my supplier, ATC! They have been really good to work with. I used them for the rebuild kit for my 4L30E and for a buddy's Dodge A618. BTW, their rebuilt torque converters are excellent quality, I would recommend them.

[winfred]

not sure i want to ship in tranny jobs, sounds like something that could bite me in the ass, i've gotten a few in that were screwed royaly and i didn't want to mess with, and at the moment i am not comfortable with full rebuilds and or valve body work. one of my favorite ones was a 85 528e, he brought me the tranny and on inspection the whole a-clutch basket was blown apart, i repared it with used hard parts, a week later the car comes in on the hook, i tear it down and a-clutch is blown up again, it turns out he had the throttle blocked open to mask a running problem and the car was idling at about 2500, so every time he put it in gear it was like a neutral drop chirping the tires

[G Feller]

In a good way of course. Perhaps that's what it takes to become a motor master?

Some of us can only dream.

[George M]

who did the neutral slams. See what you mean. Tranny work is tough...both in pulling the trans, repairing them and then seeing if they stay together after the fact....why Kirt Koeller bought a dyno for his shop so he could test everything he rebuilt...a lot of steps involved...best to check one's work if possible and a dyno helps.
Have you ever had the autobox apart on your 535i?
George

[George M]

further commentary on tranny work. In some ways tranny work reminds me of suspension work. The issue of piece mealing or patch working a repair comes to mind.
Because it is such a big cost to pull a trans out...may make more sense to have an entire rebuild...a bit more of an insurance...there are no guarantees...more likely however that a rebuild will go longer than a patch worked fix...say just the A-clutch replaced. The $64K question always is...WHAT are you getting with a rebuild..how many parts are replaced etc....new pump...all new seals?...new stator shaft?...new solenoids?...new valve body?....or only a patch worked tranny put back together from a generic core of unknown past under the guise of a fully rebuilt trans...that is the daunting question whenever biting the bullet for a so called "fresh" rebuild autobox.
Comes down to dollars and cents. If the patch work is much less cheaper than a full rebuild..may be the way to go...still begs the question...what are you getting with a full rebuild...all new or mostly new internals?...unlikely...or a warmed over patch work trans that works ok for the time being.
George

[ryan roopnarine]

commenting on my driveshaft posting below? thanks.

[Joe]

Thanks.

Most helpful, got my haynes manual in the post, so as soon as it arrives we begin!

Thanks again.

[MicahO]

Great post - incredible information. I don't think I'll ever venture in there, but for anyone who is getting screwed by a tranny shop - here's the guide!

Wrong tranny, but about 2 weeks ago, the tranny on my former 525iT went out. I've avoided talking to anyone bimmer related for a while, I had this crazy though of buying the car back (sold it to my neice's fiancee) and sending it out to Brett Anderson. I really didn't need any of you merry band of misfits convincing me that it would be a great idea!!!


;)


--Micah

[winfred]

i was lucky on my 535, it has a factory reman in it that's not even dirty yet, if i had to guess it has 50-60k on it (i've put about 26k in two years), if i have it long enough ill get into it, they never put the improved seals in the factory trannys (if you order a rebuild kit it comes with the steel seals) the sweetest zf i've driven is in moms 80k mile 90 325isa, if your easy on the throttle you don't even feel it shift, if you ass down on it, it chirps 2nd and down shifts nicely. as for rebuilds all but the best shops are going to reuse a lot of the hard parts, which is not too bad, but the best shops are going to charge about the same $ as the dealer for a zf reman which id rather have, we got one for a friend of the shop for his e32 735, if i remember right it was about $1200


who did the neutral slams. See what you mean. Tranny work is tough...both in pulling the trans, repairing them and then seeing if they stay together after the fact....why Kirt Koeller bought a dyno for his shop so he could test everything he rebuilt...a lot of steps involved...best to check one's work if possible and a dyno helps.
Have you ever had the autobox apart on your 535i?
George

[Unregistered]

My '89 525iA (224,000 km) has been sitting motionless since early Dec 2003 with tranny problems. Can you comment on my symptoms matching your fix? I drove the car about 20 miles around town, then at the bottom of a gully with steep climbs either way out it stopped making headway. Having heard of this problem with the early E34's I coasted backwards up a driveway and turned around thinking that I could drive the remaining half-mile home in reverse. However, left it parked there because reverse was like driving with the hand brake on. Lots of resistance, whereas forward just didn't grab at all. I left it there for four days until I could borrow a 4wd truck on the weekend. When I went back for the car it drove fine again, at least the last half-mile back home. Reversing it up my driveway it again developed the heavy resistance after reversing about 30 feet.

It's the problem in reverse that has me worried that the standard fix, your beautifully documented procedure, isn't going to go deep enough to get me back on the road again.

Thanks for your feedback...

Bill K. in Sydney, Australia

[winfred]

could be a fluid problem, like a clogged filter. generally when the clutches crap, it's toast

[George M]

so you are saying Winfred that for your money you would prefer a factory remanufactured ZF tranny sold from a BMW dealership? versus a trans from a good rebuilder...because the no. of parts changed/seals replaced etc. will be greater with a remanufactured trans?
Thanks,
George

[TimGinCentralNJ]

...in the ZF's beginning in around mid/late-'88 in the ZF-HP422E (I believe was the model). The story I read indicated BMW (although never admitting this issue was worthy of a full "recall", of course) came up with a retrofit valve of some sort to allieviate the well-known blown clutch pack issue occuring when the tranny was revved for extended periods in "N" or "P". This valve was later incorporated into the '88 and later ZF-HP line of trannies.

Is my info way off base? Are we talking about the same problem? (I haven't had coffee yet--pls be gentle with me.)

Thanks for posting this info...always wanted to see the "inner-workings" of this issue...and having it well-narrated helps tremendously, too.

Rgds,
Tim G.
'91 535iM
ex-'91 535iA with ZF-HP422 (stolen, recovered & scrapped)

[George M]

follow up question...you show the A-clutch pack repair/replacement...how about the other 3 clutch packs? In your experience, do these ever seem to fail or is it almost always the infamous A-clutch and the other clutches never experience any overpressurization and therefore by comparison go much bigger miles?
Thanks,
George

[winfred]

if they fixed it, i've not seen it i have done them through the last of the zf's on 92-93 m30s, and if you get the big rebuild kit it comes with the steel seals, the teflon seals are a aftermarket thing. as for rebuilds, for the same money ill take a factory reman over a indy, unless the indy is something special, i look at it like ac compressors, a good 1/2 of the remans on the market are not worth the box they came in, but factory units have the best record for out living the warranty by a good amount.
one quick and ugly test i do, get the back of the car off the ground and let it run in neutral, see if the tires spin more then a little, a real good one won't, a avarage one barly spins, and a turd hauls ass and is hard to stop with your hand

[winfred]

george i forgot your 2nd q, i've gone past 2nd a few times looking around and the clutches are hardly touched, and are still a light tan, when 1st blows up bad ill toss some 2nd clutches in for safety, because 1st gets real hot. i think a-clutch soaks up all of the abuse and saves the rest of the unit, about the only other failure i happen upon some abused trannys will cough up their planitary gears, at which point i sell them a used tranny or if i have a good case (from 2nd back) build that

[DrewZ]

I think a straight-up 5-speed swap might not even need a visit to OH. Maybe my local guy that works for $50-ish/hour could do it . . .


Great post - incredible information. I don't think I'll ever venture in there, but for anyone who is getting screwed by a tranny shop - here's the guide!

Wrong tranny, but about 2 weeks ago, the tranny on my former 525iT went out. I've avoided talking to anyone bimmer related for a while, I had this crazy though of buying the car back (sold it to my neice's fiancee) and sending it out to Brett Anderson. I really didn't need any of you merry band of misfits convincing me that it would be a great idea!!!


;)


--Micah

[George M]

I haven't performed that test yet on my car but my car in neutral shows no sign of initiating the A-clutch to move the car forward...YET!...hehe.
Of course that is pushing on the whole car. With the car in the air and just pushing on the rotational inertia of the driveline...your test is the proof of the pudding.
All great input Winfred...Thanks,
George

[MicahO]

pppplease stop tempting me.....

;)

[George M]

Based upon install of a B or 2nd gear clutch pack Winfred...is it that much more effort/deeper dive into the trans?...can you get to the B pack from the front?
Thanks,
George

[MicahO]

I still have to work out where the replies get inserted - this was for Drew :)

[Scott H]

BTW that was for YOU DREW ;)

[winfred]

in the pic of the rest of the tranny you are looking at the b-clutch


Based upon install of a B or 2nd gear clutch pack Winfred...is it that much more effort/deeper dive into the trans?...can you get to the B pack from the front?
Thanks,
George

[George M]

thanks brother.

[DrewZ]

$6k for an extra 130hp . . .
http://www.esstuning.com/img/mvc-220.jpg


BTW that was for YOU DREW ;)

[DrewZ]

You know you want to do it. :p


pppplease stop tempting me.....

;)

[rickm]

Two ZF 4HP22 repairs (http://www.bimmer.info/forum/showthread.php?p=4611#post4611)

(pictures now at bimmer.info so Winfred can reclaim some of his webspace.)

[winfred]

ill bump it once then clear out my space

[Paul in NZ]

and a turd hauls ass and is hard to stop with your hand

[winfred]

that fart had a bump in it

[George M]

darn...trans link pics wouldn't load. Winfred must have pulled them off this site. Will try to find out where the pics are let the board know.
George

[winfred]

post #31 has the link

[Bill R.]

Then you can look at the procedure in the TIS under Service/automatic transmission/240387000/ service action... Its virtually the same procedure there.








darn...trans link pics wouldn't load. Winfred must have pulled them off this site. Will try to find out where the pics are let the board know.
George

[George M]

thanks bro...saw Rick had hosted your link after I posted...sorry for the mis-cue. Am having a good discussion with Kirt Koeller relative to what should be changed if/when one goes into one of these 4HP 22's. Have used your excellent link for insight. Will let you know what he thinks are "typical" critical parts to change.
George

[rickm]

Geo - let us know so I can add Kirt's comments to the page. PMing works better for the time being as I'm freaking swamped at work.

[George M]

Thank you Bill.

[George M]

Will do Rick...Kirt's initial response is one of taking exception to replacing the A-clutch without going through the trans. So I asked him the bottom line question...what constitutes a bonefide rebuild?...what parts does he "always" replace?...a general rule or more likely based on "specific condition of a particular trans core."
Believe his response will be the latter...I am sure not unlike what Winfred does...he goes by what the failure mode is and how it looks when he tears into it.
Kirt as a professional rebuilder may have a defined procedure for determining what parts need to be replaced as opposed to what parts are elective. Will let you know what he says...may be good supplemental info to Winfred's excellent link.
George

[George M]

need for detail :D
I believe it is an excellent addition to Winfred's review and puts into perspective the judgement call made by an expert as to what needs to be replaced versus what doesn't when rebuilding one of these transmissions.
George

Kirt Koeller's words:
I have to be honest in the fact I do not know what ZF does when it remanufactures a 4HP22 anymore. I have seen some 4HP22 with the ZF reman sticker and they were still installing the steel rings on the input shaft.

Here is what I do everyday:
Start with a core and do a visual inspection of the converter (gets replaced but might be a cause of a failure so you look at it) and the case itself. Now it gets completly torn down, valve body go to another table for later work. I now put on another table what I am going to replace on EVERY 4HP22 tranny. Starts with a paper and rubber kit (gaskets seals and o-rings) steel kit (which not only has steels but also the pressure plates) friction kit (steel and friction kits will differ between differant applications of the unit) and a solinoid kit (if electronic) and speed sensor. I get the case clean and dry and take a straight edge to check the case for warpage at the vavle body mating surface. Then I start with the pump, some need new pumps some don't judgement call here. All the rubber is replaced and a new bushing is installed most of the time another judgement call but most of the time it gets replaced (with a 4HP24 bushing it works better) Then I clean all the hard parts that are not clutch drums and use my judgement if I can reuse it or need new example is the planetary I usally reuse this as I never see them go bad unless they are in a Rover application. Look at all of the needle bearings sometimes they are fine and some need to be replaced. Then I move on to the clutch pack drums. This is where I take extra care making sure the drums themselves are in really good shape or I will get another one no real room for errors here. Replace all the frictions and steels and replace the pistons o-rings. Once all the drums are done you move on to the valve body at another bench. Same procedure here as with the tranny. Visual look, tear down, clean, inspect and reassemble put new solinoids on and a new speed sensor. Now you are ready to reassemble the whole unit. When done put reman converter in it and dyno it and send her to her new home. As you are aware there is a lot of grey area on what hard parts need to be replaced and that is where you seperate the men from the boys so-to-speak. I have been doing this for a while now and I have seen other peoples work from mom and pop places to the big reman places and seen good and bad from both. There is no real industry standard when it comes to what does make a reman unit vs. a rebuilt unit Too many grey areas to make a clear cut call on that. Remember that this is in no way a complete idea on what I do to every unit somethings are just to time consuming to go into and some are just my trade secrets I'd share them but you know I'd have to kill ya!(j/k) I know that what ever I do the tranny has to last for years to come so that is always in the back of my mind and I look at it as if it was my personal tranny. Kinda corny but thats how I feel. I will tell you this if a rebuild shop (or reman factory) tells you they replace everything with new they are lying through there teeth. I priced it on a 4hp22 with ALL new parts and it was a price that not many could afford (I belive it was 8 or 9K).

[mamilapon]

Hi Winfred, I drive a 535is manual E34 1990, but because my wife does not want to drive manual I am now looking at selling it and buying an auto probably 1992-93. What I have been hearing about 4HP22EH's freaks me out! I could use some good advice.What should I do? Leister,Sydney OZ

[winfred]

it's not a bad tranny as a matter of fact i am in care of 3 of them, one in my 535, one in moms turbo diesel volvo and one in her current daily driver a 90 325is, in general they perform well and last a good while, it's a plentiful tranny so most transmition shops should know their way around it, all bimmers from 84-90 a lot of 7 series volvos and peugot's and i am willing to bet several other euro market cars that are running around. a quick and dirty test is jack up the rear end and watch the rear wheels with the car idling in neutral and warmed up the wheels shouldn't turn, if they do then only just barly when revved lightly, it's ok if they spin when the car is warmed up like the car is in gear it's only a matter of time till it's needs a a-clutch rebuild like i described, this test is not guaranteed to sniff out a dieing tranny


Hi Winfred, I drive a 535is manual E34 1990, but because my wife does not want to drive manual I am now looking at selling it and buying an auto probably 1992-93. What I have been hearing about 4HP22EH's freaks me out! I could use some good advice.What should I do? Leister,Sydney OZ

[mamilapon]

it's not a bad tranny as a matter of fact i am in care of 3 of them, one in my 535, one in moms turbo diesel volvo and one in her current daily driver a 90 325is, in general they perform well and last a good while, it's a plentiful tranny so most transmition shops should know their way around it, all bimmers from 84-90 a lot of 7 series volvos and peugot's and i am willing to bet several other euro market cars that are running around. a quick and dirty test is jack up the rear end and watch the rear wheels with the car idling in neutral and warmed up the wheels shouldn't turn, if they do then only just barly when revved lightly, it's ok if they spin when the car is warmed up like the car is in gear it's only a matter of time till it's needs a a-clutch rebuild like i described, this test is not guaranteed to sniff out a dieing tranny

[mamilapon]

You mentioned Bimmers between '84-90, would a 535i 1992/93 model have the same problem?

[winfred]

later 535s included, the dohc motor cars started using the gm (chevy) tranny, id be happyer with the 4hp22, less problems


You mentioned Bimmers between '84-90, would a 535i 1992/93 model have the same problem?

[mamilapon]

Thanks mate, all the best from down under!!

[Bimmer Nut Ed]

also see
http://www.bimmer.info/~rickm/trannyrepairs.htm


Thanks mate, all the best from down under!!

[shogun]

Link updated now here http://bmwe32.masscom.net/moswald/zf4hp22_rebuild/zf4hp22_rebuild.html

Selector Shaft Seal Replacement http://bmwe32.masscom.net/dutch740/selectorshaft/selectorshaft.htm

Driveline & Transmission Gearbox Replacement http://bmwe32.masscom.net/johan/gearbox_swap/gearbox_swap.html

Gearbox Rear Seal Replacement http://bmwe32.masscom.net/johan/gearbox_seal/gearbox_seal.html

[shogun]

additional for the collection of info
Automatic transmission, output shaft seal replacement http://www.nmia.com/~dgnrg/page_23.htm
pics: ZF4HP22, ZF4HP24, Stator Shaft Cross Leak Kit (Superior) (1984-Up) (K4HP22) https://cobratransmission.com/zf4hp22-zf4hp24-stator-shaft-cross-leak-kit-3006097-1
http://transmissiontechnologies.com/Kit-Shaft-Stator-Cross-Leak-ZF4HP22-ZF4HP24-ZF-Group-84-UP.aspx
Problem Solver, * Helps correct burned forward clutches, slipping in drive, reverse only, creeping in neutral, short life rebuilds. * Kit includes the no go tool to test stator support condition. Custom composite teflon stator rings. Buffer wheel and forward clutch piston modification information with drill bit.

Teflon seals replacement, Converter seal replacement https://web.archive.org/web/20130612220634/http://www.disgruntledgoat.com/content/vehicles/dakar/ZF4HP22.php
text copied:
'A' clutch burnout - Teflon Seal replacement
I took a few pics of core tranny parts to give a strong idea on how to repair this common defect, this tranny is in m20 bimmers, m30 bimmers after about 84, volvo 740 without overdrive non turbo, Peugeot and jag don't know which. this is how to repair the main problem with the tranny, when the car will only move in reverse and in extreme cases not move at all.

This is the cause of the problem, these steel seals leak and send pressure to the 1st gear clutch pack and burn it up. Teflon seal locations

These are the bolts to take out to remove the bell housing and pump as a unit, unless you need to replace the converter bushing you do not need to take the pump apart or off of the bell housing (I will describe the procedure for that and why at the end of the post). Bellhousing bolt locations

Here's the bell housing / pump assembly off:
Here's the front of the rest of the tranny and case:
Grab the A-clutch basket and yank it out of the bellhousing / pump assembly:
Here's the back side of the A-clutch basket, there's a steel bearing surface missing in this pic that you will have - between all rotating parts there's a bearing race (looks like a washer), flat roller bearing and another race:
You can leave the shaft in the A-clutch basket or pop it out so the basket will sit flat on a bench; or you can just leave the whole thing in the bellhousing / pump assembly while you do the clutches. There's a spring clip that holds the basket together that you remove with a screwdriver:
Inspect the basket for cracks, I've found a few blown up from people who didn't take no for an answer. Also inspect the groove the spring clip was in: those ears can snap off:
Here's the pack of disks and plates - there's a black wavy disk on the top and bottom of the pack that you re-use:
This pressure plate is under all of the clutches, you can see some of the burnt clutch on it, clean that off and clean under it:
Here's a new disc and steel - soak the discs in fresh ATF for a few minutes before installing
With the teflon seals there should be a drill bit and a sandpaper flap drill thingie - I've never drilled the hole in the 25-30 trannys I've done, it's up to you. It is done to relieve any future leak pressure, I've been doing these for over 5 years and have yet to have one of my repairs fail. The sandpaper drill thingie is used to knock down any burrs left from the steel seals here:
Seals...and where they go:
After cleaning the bore by honing it, stick the input shaft back in the A-clutch basket (if you removed it) and lube the seals and bore with ATF. Make sure the three pieces of the bearing are in place and slide the A-clutch assembly back into the bellhousing / pump assembly. It will seat with a thunk and spin freely.
Put this bearing race on the of the input shaft/a-clutch assembly, then the bearing and last the other race, it will be the smallest of all the races:
Then insert this gear into the A-clutch assembly......until it's bottomed out in the clutch pack:
If you didn't break the paper gasket that seals the pump to the tranny you can reuse it as a new one is a bitch to fit onto the pump without ripping it.

All that's left is to reinstall the bellhousing / pump assembly into the tranny - get comfy as this can be fun sometimes! The object is to slip the fingers on the back of the A-clutch into the slots of the 2nd gear clutches in the tranny case. Twisting the input shaft helps - you have to 'feel' your way in. There will be no gap between the pump and tranny case when seated. Tighten the 17mm bolts in a cross pattern, and you are done.

Take your time: look carefully at how everything came apart, and if in doubt dump ATF all over it if it's inside of the tranny! The Bentley manual has an exploded view of the tranny if I remember right.
When installing the torque converter, make sure it's all the way in: If the tranny and motor won't go together find out why, don't pull it together with the bolts as you can destroy the pump and converter.
I get most of my parts from these guys, but there's almost always a tranny parts place or two in town.
Converter oil seal
If the converter seal you just replaced is leaking again, the bushing behind the seal has walked forward and is blocking the drain: Time for a new bushing! It's hiding here:
Take the bell housing pump assembly off as seen in the a-clutch repair and take the rest of the bolts out of it and separate the pump from the bell housing and take the bolts out of the back of the pump - you can thenstrip the pump all the way down and press the new bushing in. Reassembly is covered in the A-clutch repair.

http://bmwe32.masscom.net/moswald/zf4hp22_rebuild/zf4hp22_rebuild.html

[shogun]

ZF 4HP 22 transmission service manual for download http://gershon.ucoz.com/ZF/powertrain-zf.pdf