SLROC Forum

Hi Everyone,

I am just about to embark on putting a series 2A gear box into my Series 3 Diesel 88 but before I go to the effort of stripping the 2A gearbox I want to make sure I know what I am getting into. So I would be grateful for answers to the following questions:

1. Putting a series 2A gear box into a series 3 seems to be a popular option and I have read and been told it is because "they are stronger" - but no one is able to tell me in what way they are stronger. So, is this urban myth- how are the 2A boxes stronger than the series 3 boxes?

2. On the 2A boxes there is no syncro mesh on first and second gear. How will this effect my driving, how would I need to approach changing gear as opposed to when using a fully syncroed box?

3. Are the bell housing the same or will I have to swap them - will the series 3 housing fit onto the 2A box?

4. Presumably, if I swap bell housing I will have to change something re the clutch or can I stick to the series 3 clutch?

5. From the manual it appears that the ratios are not exactly the same. Will I notice any difference in top road speed or accelaeration in other gears?

6. Finally are there any pitfalls anyone, who has done this before, can tell me about!. The current box is jumping out of gear and does funny things off road so my plan is to strip and check everything on the 2A box and do the swap before the Series 3  box gives up totally. I presume, with a manual to hand, that stripping, checking, and replacing parts on these boxes is pretty straight forward?

Thanking folk in advance.

Stephen

Stephen,

I did this with my old series 3 maybe 16 or so years ago so i'm answering from memory.

1, there is no syncro so 1st and 2nd gears are thicker.

2, double clutch, you'll get it no time. I still find myself double clutching now just out of habit and my Ser3 went in 1996.

3, 2a box and bell housing will fit, straight swap.

4, I think i just replaced the ser3 clutch at the same time. I'm not sure if it was any different to a 2a clutch. I remember changing the clutch cylinder push rod for some reason but it might have just been due to wear.

5, I can't remember the ratios being different, or noticing any effect.

6, I had no probelms at all, can't remember any pitfalls.

Cheers, G

Many thanks Growlz -that has given me the confidence to just crack on with it- hey -maybe I'll pass on  advice from my experience of this onto someone in 2027!

cheers 

Stephen

Just get a late S3 box, they were strengthened over the lifespan of the model and the last boxes were much much better than the early ones. You will need to google fr the suffix letters that will tell you it is a late box.

Series 2a boxes have stronger lay shafts and because they dont have syncros in first and second they have thicker gears.

Double clutching is a little tricky to get a hand at it but once you get it is stays for life. ( http://www.youtube.com/watch?v=pI3cHXnGEx4 )

I had troubles fitting a series 3 box into my 2a, but I have heard people having no issues doing it so I must of just had a bitsa. One thing you need to remember is that the slave cylinders are different and the throwout mechanism is totally different but it will work with the series 3 clutch. You will also need a new pipe from the master cylinder as the slave cylinder sits in a different place on the bell housing.

To swap the bellhousing is not just as easy as you think. you pretty much have to pull the whole front off the gearbox to replace the bell housing. in the end i just took it to a transmission shop to get it swapped over as i wasn't going to stuff around with it.

The ratios wont really be an issue as the changes are very minor.

hope that helps a little
chris