Getrag 232 vs 242: Someone help..

[BVNitta]

Hey guys:

Did the '76 2002 come with Getrag 242's at all ? I have a 232 on mine. What's the difference between the 232 and the 242 ? (If the guibo is a discriminator, mine's a 4-bolt.)

Any help with my questions - greatly appreciated.

By way of explanation - I'm dropping in a 5-spd and selling the 4. The prospective buyer was under the impression this was a 242, and I was not any wiser until I cleaned it up and saw 232xxxxxx at the rear of the bell housing.

BTW, at least two online sources seem to say that the Getrag 4-spd on the '76 '02 is a 232.

http://www.metricmechanic.com/pg51.htm

http://www.rsgear.com/BrgKit02.pdf

Bhima

[Guest Anonymous]

the 232s came on earlier 02s. dont know exact years. they have the crappy porsche type syncros that wear quicly. 242 came later and have borg syncros which are better.

[BVNitta]

It looks like the later 232's came with Borg Warner synchros, according to the Metric Mechanic link above.

The question is, did the 242's ever make it onto 2002's ? Thanks again,

Bhima

[Lupin3]

Bhima, I just got your message you left on my cell - it had died yesterday. I'll call you later today.

It is somewhat confusing as to the history of '02 4 speeds. Metric Mechanic very clearly lists the 232 as being standard on all '02s throughout production, but with Borg Warner synchros on the '71 and later cars.

However, www.bimmers.com/02/ states:

Four Speed Transmissions

Getrag 232, pre-'71 2002 4-speeds with the Porsche style synchros:

1st: 3.835

2nd: 2.053

3rd: 1.345

4th: 1.00

There were several minor changes made to this transmission over its lifespan. Pre-'69 examples came with a 3-bolt output flange, to match the smaller, 6-bolt flex coupling used on the earlier driveshaft. Later cars had a 4-bolt output flange, with an 8-bolt Guibo flex coupling. The selector shaft length was also changed with the flange change, so trying to install a 4-bolt flange on a transmission originally equipped with a 3-bolt will result in a problem of the flex coupling hitting the selector shaft.

Getrag 242, '02s from mid-'71 on, most 320i 4-speeds, Borg-Warner synchros:

1st: 3.764

2nd: 2.02

3rd: 1.32

4th: 1.00

There was also a change made to the output flanges on this transmission. Early examples (pre-'76) were infamous for having the splines on the output shaft and flange wear down, sometimes to the point of shearing off, resulting in a stranded car. The fix came on late '75 cars, with a redesigned shaft and flange featuring finer splines. Most of these transmissions will have exhibited this problem by now and should have been fixed (by updating to the newer style flange and shaft). Occasionally, you can still find one of the rare ones that haven't suffered from the problem. Also, in '78, some internal modifications were made (wider first gear, etc.) to this transmission. It should be noted that the 2002 and 320i versions can be interchanged, although the clutch slave cylinder mounts differently, depending on the version. The 2002 clutch slave cylinder is pressed into a bore cast into the bellhousing, and has an exposed pushrod that pushes towards the rear of the car, while the 320i clutch slave cylinder is bolted into a lug on the side of the bellhousing, with a pushrod that is hidden inside the bellhousing, pushing towards the front of the car.

To confuse matters even further, my mechanic checked his database, which said even pre-'71 cars came with 242s, suggesting they are interchangeable. I know the trans in my '74 is a 242.

However, it does seem as though a 232 could be used, perhaps with some modification, in my '74. Normally, I'd be concerned about the Porsche synchros but, with the recent rebuild on your trans, that seems less of a worry. I wonder if you might have receipts for the trans showing that the synchros were replaced?

I'll continue to look into this, but at this point I don't see any reason not to continue with the purchase. I'll give you a call later this afternoon after I've done some more research.

Thanks for your help on this!

Lupin3 (Matt)

[Lupin3]

Well, I just got off the phone with Jim at Metric Mechanic - a very knowledgable sounding and friendly guy, I might add. He sticks to his story that all 2002s came with Getrag 232s, and that they all had 4 bolt flanges with 8 bolt guibo couplings. He says 242s only came in 320s, from 1977 on, and that they differed externally from 77 on and internally from 78 on.

Since your transmission is clearly marked a '76 and a 232, I think Jim must be right. My mechanic told me my trans was a 242, but I suspect that was because that's what his database told him. As far as I know, my box is original and has never been serviced by my mechanic, so I don't think he's seen the part number.

It's odd, though, that bimmers.org, which seems a very knowledgable site, has such conflicting information in such detail. Just out of curiosity, I'll email Ben Thongsai to see what he says.

Anyway, sorry to have caused such confusion. I got your email this morning and everything seems perfect. I'll call you later this afternoon, and we can proceed with the purchase as planned through the UPS Store. I appreciate you taking the time to follow up so thoroughly with this little mystery!

[BVNitta]

Good work - thanks mate. Talk to you soon.

Bhima