Series 2a gearbox ID

[Land-lord]

Hi.

Can anyone advise how I can identify a s2a gearbox please?

Differences between the 2 and 1 - when compared to the 2a?

THanks

[JDNSW]

Hi.

Can anyone advise how I can identify a s2a gearbox please?

Differences between the 2 and 1 - when compared to the 2a?

THanks

There were progressive changes that did not occur at either the change 1 to 2 or 2 to 2a, so there is no real answer to your question. The key is the gearbox number suffix, and there are significant changes with each of these changes. All of the changes seem to have been improvements, so you would want to look for the highest letter you can find!

John

[Land-lord]

John,

How do I locate the gearbox serial # from above or below?

The gbox is currently hooked up to engine in normal position.

What numbers indicate a 2a box?

THanks

[JDNSW]

John,

How do I locate the gearbox serial # from above or below?

The gbox is currently hooked up to engine in normal position.

What numbers indicate a 2a box?

THanks

To see the gearbox number you will need to remove the transmission tunnel cover, although you might manage with a mirror from below if it is clean. A 2a box is any one with a letter suffix to the number.

John

[Land-lord]

Thanks Jd.

I have now located the gbox number - thanks.

It reads "90..... A"

Is this a series 2a or 3?

THe reason I ask, because most of the s2a boxes I see being referred to start with "2"..

ANy help appreciated..

[JDNSW]

Thanks Jd.

I have now located the gbox number - thanks.

It reads "90..... A"

Is this a series 2a or 3?

THe reason I ask, because most of the s2a boxes I see being referred to start with "2"..

ANy help appreciated..

I can't find a reference to the actual numbers, but I know the S3 boxes started the letters again, in other words, start from A, but according to my reference the S3 boxes usually have the number on the actual transfer case not the gearbox, on the sloping bit of the flange that joins to the gearbox, with the number running down rather than horizontally and on the gearbox itself. (The use of the word "usually" suggests this may not be quite definitive)

However, unless the front cover and bell housing has been swapped (which is possible) it is easy to tell a S3 box from an S1,2,2a box - the S3 has the clutch slave cylinder on the left side and operating directly on the fork, where the S1,2,2a has the slave cylinder on a bracket on the right side, operating a cross shaft that in turn operates the fork.

John

[Land-lord]

box number = 90141780 A

Can you confirm now?

Did the S3 transfer case also have a 41mm int. shaft?

[Land-lord]

Number is horizontal..

what number range did the s3 gbox start from and what series number range did the s2a end?

is this blister you mentioned before cast into bell housing? If it is then I can see soemthing poking out LHS cast into housing...

[JDNSW]

Number is horizontal..

what number range did the s3 gbox start from and what series number range did the s2a end?

is this blister you mentioned before cast into bell housing? If it is then I can see soemthing poking out LHS cast into housing...

I can't tell you what the number sequences are - they are not given in the parts books, generally only talks about the letter suffix, although the S3 parts book does give a couple of numbers, showing that there are at least two sequences for the S3 box, one starting with 36, the other with 90. I have not found any indication of numbers in the S2a parts book, but I think all the boxes I have start with 2 - but that doesn't mean there are not other sequences.

The attached picture shows the distinctive mount for the slave cylinder on the S3 box - this does not exist on the S2a box, but instead has a hole in the bell housing on the opposite side through which is a shaft from the slave cylinder to the release mechanism.

John

[isuzurover]

box number = 90141780 A


That is a Series III Suffix A (first of the series 3 boxes). Should have synchromesh on 1st and 2nd. It is however, probably the weakest of all the SIII boxes, as the later ones introduced updates to the gears, synchro rings, etc. However, the seriel number of gearboxes is (unwisely) stamped on the part that is easiest to swap, so you don't really know what the box is or if it has been rebuilt with updated internals.

[Land-lord]

Hells Bells!

Another variable to consider...name plate changes...:o

[Land-lord]

Can I gut my S3 "A" box and bot stronger internals in?

If so, what should I change?

I will throw the other S3 box out to tip!

[isuzurover]

IMO the SIIA box is stronger than the SIII, but there doesn't seem to be a lot in it. SIIA boxes tend to snap layshafts (- but mine has the late model (properly radiused) layshaft in it, and has broken everything but), whereas SIII boxes tend to have problems with the 1st & 2nd synchro rings, which makes them jump out going down hills offroad - which is never fun. SIII boxes have also been known to break mainshafts.

You can AFAIK pull the whole internals out of your suffix A box, and put all new internals in, but you will be looking at anywhere between $500 and a few $000 depending on if you use new or 2nd hand gears and shafts, and how friendly you are with your parts dealer.

NB - it is impossible to get new genuine gears and shafts for series boxes (but some parts like bearings and thrust washers are still available genuine). Because of this, you have to be sure you are buying good quality parts. I once had an almost new layshaft first gear lose 3 teeth - including the roots - becaus the gear was made from a blank that was too soft, and then had been case hardened too much to compensate.

[isuzurover]

Can I gut my S3 "A" box and bot stronger internals in?

If so, what should I change?

I will throw the other S3 box out to tip!

Why are you throwing out your other box? Is either box fitted to a vehicle, or do you know if they work OK?

[Blknight.aus]

you sure can, if you want you can put the stronger internals in a 2a box, all you need to do is have the bearing journals enlarged...

the potential gearbox guts combinations are literally staggering.

then theres the tcase options :)

[JDNSW]

you sure can, if you want you can put the stronger internals in a 2a box, all you need to do is have the bearing journals enlarged...

the potential gearbox guts combinations are literally staggering.

then theres the tcase options :)

.......and heaven help anyone trying to find the right parts to fix it in future!

John

[crossy]

Hells Bells!

Another variable to consider...name plate changes...:o


LOL - welcome to rover.

[Land-lord]

Looks like I have been gutted.

No s2a box in my nest...:mad:

Here's the G O....

My plan is to build a 86" 1954 SWB from scratch.

I have a complete 88" 1957 SWB as my donor Landy right next to it..

This 88" has the S3 gbox linked to a hodlen 186.

I want to put transfer this motor/box into the 86" - for starters..

I was sold S3 box after being told it was the S2a box. Sucked in!

THoughts

[isuzurover]

What engine are you planning to use?

[Land-lord]

red 186

[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

[JDNSW]

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.Chassis_Numbers.suffix.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

[isuzurover]

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.

[JDNSW]

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

[isuzurover]

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.

[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

[JDNSW]

"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

[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

[JDNSW]

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

[isuzurover]

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

The High Ratio T-case conversion is more than just changing gears. The way the Series t-case is constructed (3 gears in-line (output, intermediate, and High Range)), you can change to any possible combination of the size of those 3 gears, and you will still have the same high range ratio. The conversions get around that by modifying the case to move the intermediate shaft to a new location. The conversion replaces ALL GEARS - including intermediate and low AFAIK.

Mal Story told me that when he designed his conversion - the most common one AFAIK - he made low range as low as he possibly could (without further case modifications). But this means about 39:1 with a standard box (slightly higher than stock).

So you can't have both unfortunately.

[JDNSW]

Thanks for the explanation - I suspected something like that.

John