5 Speed Gearbox Installation Questions

Michael Kaye

Michael Kaye

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Hi all.

I’ve finally got hold of a good 5 speed Gearbox and Bell Housing from E23 728i for installation in my E9.

I have the transmission mounting kit from CoupeKing and a hard to find seal/gasket.

My car is a 74 and now that my mechanic is investigating installation, he has some questions. Could someone in the know maybe help me give him the answers.

His Questions:

1. Can the existing four speed shifter tower be shortened to fit the five speed box or are they so different we need to find a 528 E12 shifter assembly? What is the best approach?

2. Do we need a E21 shift lever, and if so why?

3. I believe I also need a release bearing and release fork/arm, should these be from E12 or later only? Or if not what is needed.

4. Is there anything else/parts we need to consider?

Thanks in advance!

Michael
 
1. I suppose you could fabricate the 262 bracket but it is easier to just get an existing bracket which fits perfectly.
2. You don't need one, but it provides a slightly shorter throw.
3. You'll need those and the later slave cylinder too. Repace the plastic release lever bushing in the bell housing with a metal one. Stock clutch kit will have the release bearing, may as well put a new clutch in.
4. Check out my thread on linkage etc:

5 speed shift linkage bushing replacement

In preparation for my Getrag 5 speed install I have been preparing the short throw shift linkage and was not satisfied with the crappy plastic bushings that came in the new rod joint or the used 320i lever. BMW does not sell replacements for these. So I measured the size of the bores and it is...
e9coupe.com e9coupe.com
 
Hey Steve. Thanks for the reply. Couple of follow questions if I can.

Stevehose said:
1. I suppose you could fabricate the 262 bracket but it is easier to just get an existing bracket which fits perfectly.
Click to expand...

Do you know what models I should be looking to source this from?

Stevehose said:
3. You'll need those and the later slave cylinder too.
Click to expand...

Ok so if I understand correctly I need the release bearing, fork arm and slave cylinder. Again where do I source these?

Thank you, I will do.
 
I am in the middle of having this done and the shift tower listed in that thread is NLA.
5 shift platform 25-11-1-205-386
We are having the shift tower and selector rod shortened for the 5-speed.
 
halboyles said:
I am in the middle of having this done and the shift tower listed in that thread is NLA.
5 shift platform 25-11-1-205-386
We are having the shift tower and selector rod shortened for the 5-speed.
Click to expand...

You mean the original shift tower and selector rod for the 4 speed are being shortened?
 
Michael Kaye said:
Thanks. Read that doc but assumed that those part numbers just referred to the parts - didn’t realise they were still available to order.

I was assuming I would have to find second hand.
Click to expand...

Hi Michael - as Don says, you can get then new or used. If you want to hunt for used parts, which is what I did, you can use the part numbers from the Carl Nelson notes and then make a list of cars they were used on to help with the search.
 
On the shift rod, you probably or might want to buy an aftermarket one, I will try and find the brand and size if you need it, you need to get the one that is straight
 
that is a bit strange, the link to ebay is to what is 'normally' called the platform, the rod is what connects the stick you move in the car to the transmission
 
bmw30cs.blogspot.com

5 Speed Conversion

CS REGISTER - Five Speed Conversion for CS - Carl O. Nelson Many times in the past I have been asked about the difficulty of installi...
bmw30cs.blogspot.com bmw30cs.blogspot.com

BMW E9 Auto to 5SPD manual Conversion

Hi. I thought I would document the 5SPD manual conversion I am performing on my 1971 BMW 2800CS. This is intended as a reference only, please only work on you vehicle if you are confident and able, I assume no responsibility for anyones actions. BMW Parts: Transmission: Getrag 265 5SPD...
e9coupe.com e9coupe.com
 
mark99 said:
that is a bit strange, the link to ebay is to what is 'normally' called the platform, the rod is what connects the stick you move in the car to the transmission
Click to expand...

that’s what’s confusing me too. Or should I say trying to use the correct term is confusing me.

my mechanic keeps speaking about a shifter mechanism - I’m not clear whether he’s referring to the rod or the platform or something else!
 
if you look at the RealOEM for the manual 4 speed, they call the sheet metal part #6 'shifting arm', it is also called platform, which makes a little more sense, never a rod, the ebay listing is wrong, the rod at 14 and 15 on RealOEM are called selector rod
The part you move, in the car is called 'shift lever'
The 5 speed transmission is longer, they just added an extra housing to the end, so you have to get a shorter platform and selector rod to match so your shift lever will be in the right location
An FYI, there are at least 2 platforms used with the BMW 5 speed, different lengths, you have to get the right one
The platform on the 4 speed bolts only to the transmission, with the 5 speed, BMW attached the aft end to the car body, the transmission tunnel
The 4 speed way seems like a much better idea, the Coupe King kit supplies a connecting rod to attache the platform the the transmission so you don't need to attach it to the transmission tunnel

RealOEM.com - Online BMW Parts Catalog

BMW parts 2.5CS-3.0CSL 3.0CS Getrag 262 housing+attaching parts
www.realoem.com
 
Yes, the shift lever or "shifter" is the part you actually grab and manipulate to change gears. The shift platform is mounted to the transmission and must be sized to both the transmission and the opening in the floor of the car because it contains the pivot point for the shift lever. The shift rod or selector rod attaches to the transmission, and to the bottom end of the shift lever. When you move the shift lever, it pivots in the platform, moves the selector rod, which changes the gears.

I used an e21 shift lever, and find it to be a nice throw, but shift throws are a matter of personal preference. I'm pretty sure that there are numerous BMW shift levers that could be used, but I've not seen here where people have posted comparisons so I just went with what Carl recommended. I know other BMW people have done comparisons for other cars; I captured a couple of these when modifying my e39 years ago. Here is an example from the e39 guys:

Shift z43-0.jpg


I also used the shift rod Carl recommended, but if I were looking at this now, I would strongly consider the aftermarket version Stevehose used.
 
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