Automatic Transmissions?

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canada karl
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Automatic Transmissions?

Post by canada karl » Thu Jun 25, 2020 6:16 pm

I'm repairing a new to me 77 530i. Is there an easy way to tell if the automatic is a ZF or Borg Warner...markings? Was one considered more trouble free than the other?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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528i-1981
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Re: Automatic Transmissions?

Post by 528i-1981 » Fri Jun 26, 2020 5:45 am

I have no experience, but Andrew Everett's book on 5- and 6-series restoration says the Borg Warner 65 is "crude but super-reliable" and not expensive to rebuild. The 3HP22 is considered by him to be a better unit, and he recommends upgrading to it if you have a troubled BW 65 or older 3HP20 (used in pre-1975 euro-spec E12s and also E3s and E9s).

The BW is reported to have the dipstick on the passenger side, and the ZF 20/22 on the driver's side. I'm not sure about this on the E12, though. There's some useful info for identification on the E9 forum, and that might carry forward for our cars. It looks like the ZF should have a plate riveted on the left-hand side:

https://e9coupe.com/forum/threads/wich- ... box.31361/
(oo=00=oo) Eric
1981 528i Manual

tlake
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Re: Automatic Transmissions?

Post by tlake » Wed Jul 08, 2020 12:58 pm

canada karl wrote:
Thu Jun 25, 2020 6:16 pm
I'm repairing a new to me 77 530i. Is there an easy way to tell if the automatic is a ZF or Borg Warner...markings? Was one considered more trouble free than the other?
Easiest way to tell is the shifter stick, the BW-65 has an old school T-bar handle, the ZF 3HP22 has a rounded handle, like the yellow e12 in this video. So this car has been upgraded to the later type.

upgraded e12

1977 e12s and later used the ZF 3HP22. 1976 was the last year for the BW65 on the e12.

HB528i
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Re: Automatic Transmissions?

Post by HB528i » Wed Jul 08, 2020 5:32 pm

ZF 3HP-22
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keehn
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Re: Automatic Transmissions?

Post by keehn » Thu Jul 09, 2020 7:00 am

Karl,

In my experience throughout the years and various generations of bimmers (E12, E28, E34, E38, E46, E53), I have tried to avoid ZF as much as possible. They seem to enjoy "complicating" parts that have no business being complicated. I have dug through ZF and GM transmissions from my various bimmers and, time and again, ZF has more parts to break, whereas GM keeps everything modular (and cheaper rebuild parts too!). Other manufacturers, such as GM...and yes, Borg-Warner, are legendary for their transmissions, and have kept theirs to KISS-like standards. Also, GM and Borg-Warner are U.S.-based companies, where the GM automatic transmission was born (hydra-matic if I recall correctly....).

There are known truths in the automobile world, such as:

BMW's make great I6 engines (and boxers for beemers).
GM/Borg-Warner make great auto transmissions.
Getrag makes great manual transmissions.
porsche is just a fancy and fast Volkswagen.
Mercedes....um...haul BMWs to the dealership :lol:

Mike

tlake
Posts: 226
Joined: Wed Feb 03, 2010 6:33 pm
Location: WA

Re: Automatic Transmissions?

Post by tlake » Thu Jul 09, 2020 11:20 am

keehn wrote:
Thu Jul 09, 2020 7:00 am
Karl,

In my experience throughout the years and various generations of bimmers (E12, E28, E34, E38, E46, E53), I have tried to avoid ZF as much as possible. They seem to enjoy "complicating" parts that have no business being complicated. I have dug through ZF and GM transmissions from my various bimmers and, time and again, ZF has more parts to break, whereas GM keeps everything modular (and cheaper rebuild parts too!). Other manufacturers, such as GM...and yes, Borg-Warner, are legendary for their transmissions, and have kept theirs to KISS-like standards. Also, GM and Borg-Warner are U.S.-based companies, where the GM automatic transmission was born (hydra-matic if I recall correctly....).

There are known truths in the automobile world, such as:

BMW's make great I6 engines (and boxers for beemers).
GM/Borg-Warner make great auto transmissions.
Getrag makes great manual transmissions.
porsche is just a fancy and fast Volkswagen.
Mercedes....um...haul BMWs to the dealership :lol:

Mike
You're generalizing Mike. :) The Ford C4, Chrysler A904 & 727 Torqueflites, GM THM 350 & 400 were all great, but after that there came a lot of junk. I wouldn't want a car with the THM 700R4, shifts were jerky, and jolty, hunting etc. Once the THM 350 was gone, I would go with the BW T5 manual.
I found the BW65 couldn't handle that much torque, I replaced the one in my '76 with the ZF 3HP22 almost 25 years ago and have had no problems, even with the 3.5L. With the 3.64 diff ratio it works well. The ZF 4HP22 has been a problem for some people because of revving the engine in neutral for emissions testing though. :cry:

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keehn
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Re: Automatic Transmissions?

Post by keehn » Thu Jul 09, 2020 12:23 pm

tlake wrote:
Thu Jul 09, 2020 11:20 am
keehn wrote:
Thu Jul 09, 2020 7:00 am
Karl,

In my experience throughout the years and various generations of bimmers (E12, E28, E34, E38, E46, E53), I have tried to avoid ZF as much as possible. They seem to enjoy "complicating" parts that have no business being complicated. I have dug through ZF and GM transmissions from my various bimmers and, time and again, ZF has more parts to break, whereas GM keeps everything modular (and cheaper rebuild parts too!). Other manufacturers, such as GM...and yes, Borg-Warner, are legendary for their transmissions, and have kept theirs to KISS-like standards. Also, GM and Borg-Warner are U.S.-based companies, where the GM automatic transmission was born (hydra-matic if I recall correctly....).

There are known truths in the automobile world, such as:

BMW's make great I6 engines (and boxers for beemers).
GM/Borg-Warner make great auto transmissions.
Getrag makes great manual transmissions.
porsche is just a fancy and fast Volkswagen.
Mercedes....um...haul BMWs to the dealership :lol:

Mike
You're generalizing Mike. :) The Ford C4, Chrysler A904 & 727 Torqueflites, GM THM 350 & 400 were all great, but after that there came a lot of junk. I wouldn't want a car with the THM 700R4, shifts were jerky, and jolty, hunting etc. Once the THM 350 was gone, I would go with the BW T5 manual.
I found the BW65 couldn't handle that much torque, I replaced the one in my '76 with the ZF 3HP22 almost 25 years ago and have had no problems, even with the 3.5L. With the 3.64 diff ratio it works well. The ZF 4HP22 has been a problem for some people because of revving the engine in neutral for emissions testing though. :cry:
Tlake,

Of course I'm generalizing :lol: Case in point: I had to order a master rebuild kit with steels for my 2013 Buick Enclave due to the radiator/trans cooler leaking together, so no, GM has some turds in their portfolio as well. But whatever magic BMW endows upon the GM's that it selects, they seem (generally, of course) to perform better than ZF counterparts.

However, I also have experience tearing into ZF transmissions and have found they are generally more complicated than their GM counterparts. I have my old ATSG manuals on both the GM and ZF trans for the E38 class somewhere in my clutter that I read cover to cover, remarking at the stark comparisons between the two machines. I remember mildly annoying my wife and amusing my kids when I would point out the differences while watching TV on the couch! :lol: At one of my old duty stations (San DIego - GREAT weather, but PRICY!) I owned a 98 E38 that had the ZF trans. Well, it broke down on me, and I went to one of the many pick-and-pulls in the area and sourced the GM equivalent. I don't remember the specifics, but all I had to do with that trans was remove ALL of the fluid, refill with filter, and bolt it back in. Yes, of course I put a new torque converter in. I was pleasantly surprised when I didn't have to use WinKFP to re-code the new transmission; it just bolted up and ran well. Unfortunately, I sold the girl when I PCS'd to my next duty station, as was the way of things when I was still in the Navy :cry:

Mike

tlake
Posts: 226
Joined: Wed Feb 03, 2010 6:33 pm
Location: WA

Re: Automatic Transmissions?

Post by tlake » Thu Jul 09, 2020 2:56 pm

keehn wrote:
Thu Jul 09, 2020 12:23 pm
tlake wrote:
Thu Jul 09, 2020 11:20 am
keehn wrote:
Thu Jul 09, 2020 7:00 am
Karl,

In my experience throughout the years and various generations of bimmers (E12, E28, E34, E38, E46, E53), I have tried to avoid ZF as much as possible. They seem to enjoy "complicating" parts that have no business being complicated. I have dug through ZF and GM transmissions from my various bimmers and, time and again, ZF has more parts to break, whereas GM keeps everything modular (and cheaper rebuild parts too!). Other manufacturers, such as GM...and yes, Borg-Warner, are legendary for their transmissions, and have kept theirs to KISS-like standards. Also, GM and Borg-Warner are U.S.-based companies, where the GM automatic transmission was born (hydra-matic if I recall correctly....).

There are known truths in the automobile world, such as:

BMW's make great I6 engines (and boxers for beemers).
GM/Borg-Warner make great auto transmissions.
Getrag makes great manual transmissions.
porsche is just a fancy and fast Volkswagen.
Mercedes....um...haul BMWs to the dealership :lol:

Mike
You're generalizing Mike. :) The Ford C4, Chrysler A904 & 727 Torqueflites, GM THM 350 & 400 were all great, but after that there came a lot of junk. I wouldn't want a car with the THM 700R4, shifts were jerky, and jolty, hunting etc. Once the THM 350 was gone, I would go with the BW T5 manual.
I found the BW65 couldn't handle that much torque, I replaced the one in my '76 with the ZF 3HP22 almost 25 years ago and have had no problems, even with the 3.5L. With the 3.64 diff ratio it works well. The ZF 4HP22 has been a problem for some people because of revving the engine in neutral for emissions testing though. :cry:
Tlake,

Of course I'm generalizing :lol: Case in point: I had to order a master rebuild kit with steels for my 2013 Buick Enclave due to the radiator/trans cooler leaking together, so no, GM has some turds in their portfolio as well. But whatever magic BMW endows upon the GM's that it selects, they seem (generally, of course) to perform better than ZF counterparts.

However, I also have experience tearing into ZF transmissions and have found they are generally more complicated than their GM counterparts. I have my old ATSG manuals on both the GM and ZF trans for the E38 class somewhere in my clutter that I read cover to cover, remarking at the stark comparisons between the two machines. I remember mildly annoying my wife and amusing my kids when I would point out the differences while watching TV on the couch! :lol: At one of my old duty stations (San DIego - GREAT weather, but PRICY!) I owned a 98 E38 that had the ZF trans. Well, it broke down on me, and I went to one of the many pick-and-pulls in the area and sourced the GM equivalent. I don't remember the specifics, but all I had to do with that trans was remove ALL of the fluid, refill with filter, and bolt it back in. Yes, of course I put a new torque converter in. I was pleasantly surprised when I didn't have to use WinKFP to re-code the new transmission; it just bolted up and ran well. Unfortunately, I sold the girl when I PCS'd to my next duty station, as was the way of things when I was still in the Navy :cry:

Mike
By the time the V8 7 series came around they were on the 5HP 22, or later? Those are really a generation beyond. The old BW-65 and the earlier ZF 3HP 20 used old fashioned brake bands, that could stretch. The 3HP 22 used a Simpson gearset and clutches, which was US practice, and this was definitely better. I heard they beefed up the 3HP 22 for the M90 and M102 engines, but never did find out what changes they made.

I know the old ZF 3HP 20 had a bad rep. Road & Track said their publisher bought a 1969 2800 and the magazine said it was their worst experience with an automatic ever. That said, they had tried this gearbox in the 1800s and 2002 and in those tests they said it worked well. So maybe it was a case of adjustment :?:

Later on in a UK magazine, maybe Autoweek, they were trying the Corvette with the new LT1 engine and I think the car's 4L60 gearbox was anything but smooth, whereas the Jag XJS' GM THM 400 was ultra smooth. Jaguar kept using that THM 400 right to the end of the XJS's life. The only reason GM stopped using it, apart from lack of an overdrive ratio, was because it clashed with the catalytic converter. :cry:

canada karl
Posts: 737
Joined: Tue Jan 06, 2009 3:50 pm

Re: Automatic Transmissions?

Post by canada karl » Thu Jul 09, 2020 4:39 pm

In any event the Getrag 265 5 speed is the best gearbox for an E12. More fun to drive and better gas mileage. IMHO :)
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

tlake
Posts: 226
Joined: Wed Feb 03, 2010 6:33 pm
Location: WA

Re: Automatic Transmissions?

Post by tlake » Fri Jul 10, 2020 1:59 pm

canada karl wrote:
Thu Jul 09, 2020 4:39 pm
In any event the Getrag 265 5 speed is the best gearbox for an E12. More fun to drive and better gas mileage. IMHO :)
I know a lot of people get bugged by the highway cruising, but the old Getrag 262 4 speed was nice. The earlier ZF (it had BW synchronizers) 4 speed had a lighter feel, but the 2nd gear synchro got worn with the 2.8L, so for 1972 the 4 speed got beefed up for the new 3 liter.

By late 1971 ZF was more than half owned by Borg-Warner.

I think unless you live on the German autobahn, you need a 3.64 or 3.45 diff ratio with the overdrive 5 speed. To think in Europe you could get the overdrive 5 speed with the 3.07 diff :!: :shock:

If you do a lot of stop start town, suburban driving, a Euro 3.5 and auto could help. In the lighter 5er it does a lot better than even in the 6 series. :)

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