Thread: Series 2a gearbox ID

Originally Posted by Land-lord

See link:
http://www.lrfaq.org/Series/FAQ.S.Ch...uffix.IIA.html

Apart from suffix B, it seems the suffix changed on the 2a box when other non-related mods occurred to vehicle during it's life....

Is this correct?

If so, then can I assume that the s2a box did change post Suffix B after remaining life?

THanks

Link is corrupted - I assume it is http://www.lrfaq.org/Series/FAQ.S.Ch...uffix.IIA.html - I looked at the site, I think I found what you are referring to.
The suffix number on the box changed only when changes were made to the box, and not just because the chassis number changed - and there are significant differences between B & C suffix - for example, gear ratios changed.

John

John is correct:

Suffix A - small t-case intermediate shaft (everything basically same as SI and SII)
Suffix B - larger intermediate shaft, but still 2.89:1 low range and tall main gearbox gears.
Suffix C - 2.35:1 low range and lower gearbox gears (overall low range ratio stayed the same)
Suffix D-E - not sure exactly, but somewhere along the way the layshaft was changed to an improved design with properly radiused section changes which made it much stronger, plus a few other minor updates.

Incidentally, many people (myself included) have fitted suffix B low range and intermediate transfer gears to our t-cases. This drops 1st low from 40:1 to 49:1.

Originally Posted by isuzurover

Incidentally, many people (myself included) have fitted suffix B low range and intermediate transfer gears to our t-cases. This drops 1st low from 40:1 to 49:1.

I've thought about it, but not actually done it!

John

Originally Posted by JDNSW

I've thought about it, but not actually done it!

John

Definitely worth the effort. Cost me about $300 for the two gears brand new.

"Incidentally, many people (myself included) have fitted suffix B low range and intermediate transfer gears to our t-cases. This drops 1st low from 40:1 to 49:1."

Is this hard?

I reckon that's a great idea! Best of both worlds then...

Just out of curiosity - I understand that initial S3 boxes are weaker - but I thought as years go by, technology woudl improve and better components, material, etc.. Why did LR go backwards for a while there with these early S3boxes?

THanks

Originally Posted by Land-lord

"Incidentally, many people (myself included) have fitted suffix B low range and intermediate transfer gears to our t-cases. This drops 1st low from 40:1 to 49:1."

*Is this hard?

I reckon that's a great idea! Best of both worlds then...

**Just out of curiosity - I understand that initial S3 boxes are weaker - but I thought as years go by, technology woudl improve and better components, material, etc.. Why did LR go backwards for a while there with these early S3boxes?

THanks

* Involves pretty much complete disassembly of the transfer case to replace two gears. Of course, while at it you would replace anything else that needed it and probably replace all seals, bearings, gaskets and O-rings as a matter of course. According to the manual this can be done without removing the transfer case. Not a very small job but not really very hard either.

**The reason the S3 box was a new design, was to extend synchromesh to all forward gears. (The original Landrover gearbox I believe first appeared in 1932 in Rover cars, when synchromesh on ANY gears was considered an innovation.) To avoid making changes to the rest of the vehicle, and remembering that the all synchro box was phased in during the last of the 2a production, the dimensions had to be kept exactly the same, otherwise you would be looking at different prop shafts, gearbox mounts on the chassis and so on. This meant that more works had to be fitted in the same space (changing first to constant mesh and adding synchro clutches to it and second), and it is hardly surprising that the box was found to be a bit wanting. Also, remember that by then the 2a box had been modified with over twenty years of experience in Landrovers alone, fixing weaknesses as they showed up. The works of the S3 box were all new, so it is hardly surprising that weaknesses showed up.

John

Excellent point and explanation. thanks.

I will have the transer case on a bench - so it may a good time to perform this mod -

Do u think I can also perform the ratio converison as well as the 1st gear stuff at same time?

Thanks

Originally Posted by Land-lord

Excellent point and explanation. thanks.

I will have the transer case on a bench - so it may a good time to perform this mod -

Do u think I can also perform the ratio converison as well as the 1st gear stuff at same time?

Thanks

If I understand your question correctly, I don't think you can fit both the high ratio transfer gears and the suffix B low range to the same box - because both may involve a replacement intermediate gear, which is, I suspect, only available for the most common transfer box, suffix C. This intermediate gear actually has two gears on the one piece of metal, one used in both ranges, the other only in low range. It may be possible, but I don't have full details of the high range conversion. If the high range conversion includes a replacement of the intermediate gear, it can't be done.

John