940 transmission - AW or ZF?

Hi there

My friend and I have checked out a '90 940, with automatic transmission. On
the base of the gear lever, it says: "P R N D 3 2 1". I have a 240 with the
AW 70 3-speed + O/D, and it says "P R N D 2 1" and has the O/D button on the
stick.

Doesn't this 940 have a ZF-transmission since it lacks the O/D button, and
has a "3"? As far as I know, the ZF (which I suspect it to be) isn't nearly
as reliable as the AW (Aisin Warner).

 

This is an AW tranny.
The OD button is located on the front side of the gearshift lever.
BD

 

This 940 has indeed got a ZF4HP22 gearbox. This box is certainly one of the
finest gearboxes made and has absolutely no problems whatsoever unless you are
an American. The Americans cannot fathom the logic behind the design which
leaves the internal pump disconnected in Park. So when revving the engine with
car stationary, the gearbox should ALWAYS be in Neutral, never in Park. Provided
you stick to the recommended ATF change intervals (30,000 miles) there will not
be a problem with this excellent piece of German engineering. I also have a high
opinion of the ZF4HP24 fitted to 400 series cars and the Three-speed ZF fitted
to one of my Lancia HPEs.

Cheers, Peter.

: Hi there
:
: My friend and I have checked out a '90 940, with automatic transmission. On
: the base of the gear lever, it says: "P R N D 3 2 1". I have a 240 with the
: AW 70 3-speed + O/D, and it says "P R N D 2 1" and has the O/D button on the
: stick.
:
: Doesn't this 940 have a ZF-transmission since it lacks the O/D button, and
: has a "3"? As far as I know, the ZF (which I suspect it to be) isn't nearly
: as reliable as the AW (Aisin Warner).
:
: --
: Keep rollin'
: Lars Vestman, Denmark.
: (My '85 Volvo 245: http://www.vestman.subnet.dk/_516019.html - in danish)
:
:

 

That's my understanding of it as well. A dealer should know for sure. If
he buys the car, tell him to NEVER rev the engine with the trans in neutral.


--






http://www.albany.net/~mjc1/index.html

 

Um, revving a car with a ZF4HP22 tranny in park is just as bad as doing
the same in neutral.

There are indeed people who love them, and people who loathe them. In
fact, it seems like many.. most? Saab 9000 owners don't find the ZF boxes
all that great. I believe that there are more issues than just the
revving it out of gear lack of lubrication. Who knows.

You can bag on Americans all you want to, but surely that doesn't make you
right. For what it's worth, the weakness was exposed due to smog testing,
not driving habits.

Indeed, I think the AW box is a terrific piece of engineering. It's
extremely durable, and on top of that it shifts fantastically.

I suppose we should all be greatful it's not a British design.

- alex

'85 244 Turbo
'84 245 Turbo

 

"Michael Cerkowski <mjc1@ albany.net ...

neutral.

OK - I'm a bit puzzled here.

"BD" believes it's an AW.
Peter Milnes believes it's a ZF, that shouldn't be revved in "P".
Alex Zepeda believes revving is just plain bad with a ZF.
And you seem to have the same doubts as I.....

Well, guys. Can I tell one from the other by checking out anything on the
car - oil dipstick?

The ride is very smooth and shifts are very nice. If it's a ZF, it seems in
excellent condition, and the car has done 160.000 mls/250.000 km's. Is
smooth shifting all it takes to buy a ZF and not worrying afterwards?

 

Alex is right. Revving the engine with the shifter in neutral will kill
the ZF transmission just as surely as revving it in park. And now if
you get a replacement box from Volvo (or BMW for that matter) they've
been modified and don't suffer from this problem. Although I've driven
740s with both AW and ZF boxes, and judging only on function the ZFs are
superior. And measured against any other standard the ZF is still very
reliable, it's just that the AW is even better.

 

PRND321 is ZF. PRND21 with OD button is AW. Don't rev ZF in park or
neutral. ZF is still a pretty good transmission, see my other post.

 

Alright. Thanks, Mike.
Say, that the prevous owner mistreated the ZF by revving, how does it act
then? Harsh shifting?
It seems that there is no way at all to test the engine (i.e. a tune up) by
revving it, is that correct?

If someone could share the ZF's actual name or part#, I would surely
appreciate it. Makes it easier to locate a possible exchange unit - if
needed (hope not!).

 

Sorry to be a wet blanket Mike, but it is OK to rev a ZF gearbox in Neutral. The
internal pump is connected in this setting and no problems will be caused. It is
the same for the three-speed ZF gearbox as fitted to one of my Lancias. Volvo
issued a notice to all dealers about this stating that they were not to rev the
engine with the gearbox in Park. I have revved my engine in Neutral many times
particularly for emissions test purposes. Max revs on my car is 5,400 rpm
(diesel). The gearbox has never given trouble when in over 180,000 miles of
driving.

Vestman, if you had read my previous post you would know the type number. For
you I will repeat, it is ZF4HP22. ZF part no. is 1 043 010 151, Volvo part
number is 1 208 301 for B230F and ZF no. 1 043 010 153 or 1 043 010 106 Volvo
no. 1 208 365 or 1 208 390 for D24T USA/Canada. Only a few transmissions have
the 1 208 390 number and some have no Volvo part number. My copy of Green Book
does not give details for B230FT, it is a bit early for that (Nov. 1985 copy).

Cheers, Peter.



: Alex Zepeda wrote:
: >
: > On Tue, 7 Oct 2003 00:16:51 +0000 (UTC), Peter Milnes
: >
: > >This 940 has indeed got a ZF4HP22 gearbox. This box is certainly one of the
: > >finest gearboxes made and has absolutely no problems whatsoever unless you
are
: > >an American. The Americans cannot fathom the logic behind the design which
: > >leaves the internal pump disconnected in Park. So when revving the engine
with
: > >car stationary, the gearbox should ALWAYS be in Neutral, never in Park.
Provided
: > >you stick to the recommended ATF change intervals (30,000 miles) there will
not
: > >be a problem with this excellent piece of German engineering. I also have a
high
: > >opinion of the ZF4HP24 fitted to 400 series cars and the Three-speed ZF
fitted
: > >to one of my Lancia HPEs.
: >
: > Um, revving a car with a ZF4HP22 tranny in park is just as bad as doing
: > the same in neutral.
: >
: > There are indeed people who love them, and people who loathe them. In
: > fact, it seems like many.. most? Saab 9000 owners don't find the ZF boxes
: > all that great. I believe that there are more issues than just the
: > revving it out of gear lack of lubrication. Who knows.
: >
: > You can bag on Americans all you want to, but surely that doesn't make you
: > right. For what it's worth, the weakness was exposed due to smog testing,
: > not driving habits.
: >
: > Indeed, I think the AW box is a terrific piece of engineering. It's
: > extremely durable, and on top of that it shifts fantastically.
: >
: > I suppose we should all be greatful it's not a British design.
: >
: > - alex
: >
: > '85 244 Turbo
: > '84 245 Turbo
:
: Alex is right. Revving the engine with the shifter in neutral will kill
: the ZF transmission just as surely as revving it in park. And now if
: you get a replacement box from Volvo (or BMW for that matter) they've
: been modified and don't suffer from this problem. Although I've driven
: 740s with both AW and ZF boxes, and judging only on function the ZFs are
: superior. And measured against any other standard the ZF is still very
: reliable, it's just that the AW is even better.
:
: --
: Mike F.
: Thornhill (near Toronto), Ont.
:
: Change cant to ca and remove parentheses to email me directly.

 

OK, I'll wait and see which one of you wins this discussion ;o)

copy).

Oops, didn't notice all the details. I've saved your data in case my friend
buys the car.

Thnx, Peter.

 

Well the service manager bulletin group 25, number 25, says to warm the
engine by driving, and goes on to say in bold type, "Do not warm the
engine by raising the RPM above idle while the transmission is in park
or neutral."

Then for the actual test:
"After the engine reaches normal operating temperature, place the
transmission into park and switch the ignition off for 30 seconds.
Restart engine. After the engine is started to not move the gear
selector through the forward or reverse gears before of during the test
sequence. DO NOT EXCEED 2000 RPM.
First stage: High Idle 1850 (+/- 150rpm) for 30 seconds
Second stage: Idle RPM (see standards for max.) for 30 seconds.

Notice there's no distinction between park and neutral. If you or
anybody else would like a PDF of this bulletin, send me an email.

 

No it burns out a clutch pack, so there's no drive or lots of slipping.
See:

http://www.swedishbricks.net/700900FAQ/Transmission-Auto1.html#ZF22
Damage in Park

 

The best use for a ZF trans is as a boat anchor.

 

I am sorry if I confused you about emissions checks, I was using the data for
diesel engine emissions testing which is different from petrol engines. Diesel
testing requires six run-ups to max rpm (set at 5400 rpm on fuel pump) holding
max for three seconds, then allowing rpm to drop to idle. The average of these
runs should be less than 3% for diesel and less than 3.5% for turbodiesel. These
values are for UK MOT test.

Cheers, Peter.

: Vestman wrote:
: >
: > OK, I'll wait and see which one of you wins this discussion ;o)
: >
: > --
: > Keep rollin'
: > Lars Vestman, Denmark.
: > (My '85 Volvo 245: http://www.vestman.subnet.dk/_516019.html - in danish)
:
: Well the service manager bulletin group 25, number 25, says to warm the
: engine by driving, and goes on to say in bold type, "Do not warm the
: engine by raising the RPM above idle while the transmission is in park
: or neutral."
:
: Then for the actual test:
: "After the engine reaches normal operating temperature, place the
: transmission into park and switch the ignition off for 30 seconds.
: Restart engine. After the engine is started to not move the gear
: selector through the forward or reverse gears before of during the test
: sequence. DO NOT EXCEED 2000 RPM.
: First stage: High Idle 1850 (+/- 150rpm) for 30 seconds
: Second stage: Idle RPM (see standards for max.) for 30 seconds.
:
: Notice there's no distinction between park and neutral. If you or
: anybody else would like a PDF of this bulletin, send me an email.
:
: --
: Mike F.
: Thornhill (near Toronto), Ont.
:
: Change cant to ca and remove parentheses to email me directly.

 

Failure from revving is nearly instant from what I've heard.

And yes, revving it in neutral will cause problems.

Here's a better description of the problem:

http://member.rivernet.com.au/btaylor/BMWText/technical/AutoGearboxZF4HP22.html

Really, unless you absolutely had to have a ZF transmission,
you might as well just replace it with an AW when the ZF fails.

- alex

 

Regardless of all this, the ZF trannies can easily be killed, whether by
ignorance or misuse or otherwise, while the AW's are virtually
indestructible, I've driven both and didn't notice much difference and
therefore if I was forced to have an automatic then the AW would be an
obvious choice. That said, I hate driving either one, fortunatly it's fairly
easy to convert to an M46.