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Geezer
7th February 2012, 09:20 PM
Hi all,

I have scoured the intermanet and am no closer to identifying this gearbox, it's installed in a Series III but suspect it is an early Series II gear box.
Casting ID on side of casing
576653CA
LM22W
A
Has Serial No 90128218 and Suffix A stamped near the top RHS.

If it is indeed an early Series II SWB, will the early RR V8 that it is currently attached to destroy it?
As I am doing a ground up rebuild of Series III, I dont want to be pulling the gearbox out after a couple of weeks.
Would I be better off getting an LT95 gearbox, which I have just discovered is suppossed to be the dogs B>>>>X for Series LR's.
Oh and I currently have a Fairey OD fitted to my current box, can this be fitted to the LT95?

Thanks for any advice on this one, I have plenty of time with car repairs and engine rebuilds, so not scared to get hands dirty. This is the problem when you buy a Puma and get the "I want an LR project" bug :o Judging by the time I've spent on this forum, there is no hope for me :eek: so I may as well get on with it :p

Cheers
G

langy
8th February 2012, 01:07 AM
Obviously the V8 has been there a fair while, otherwise you'd have said something. Keep searching about gearbox numbers, as there is a fair amount of info on it. A little refresh of memory indicates that a SII box is not necessarily a problem. ( Which gear is not syncro? It may have been rebuilt to SIII specs.) The V8/series conversion generally twists propshafts.
If the gearbox works Ok, and the oil is good - leave in it a while and stay off the loud pedal. If you want to turn the SIII into a beast, then a LT95 is a good idea - but you may have to alter a crossmember etc. Your Fairey OD won't fit the LT95, but there are a number of OD's for it floating around. Also consider a R380.

JDNSW
8th February 2012, 06:08 AM
I am not up on gearbox numbers, but from the clutch arrangement, it is a Series 3 box (although this is not definitive - the bell housing etc can be swapped with some caveats).

The Series 3 box is usually considered a little more fragile than the later S2a boxes, although late ones are probably not very different.

However, neither of these boxes is usually considered to be strong enough for the V8, and the Fairy overdrive definitely is not, although they will survive given sufficient care in driving.

The LT95 is certainly considered the strongest of the Rover gearboxes, but it is designed for full time four wheel drive, so to use it in a Series Landrover means modifications to the integral transfer case to allow part time four wheel drive or to the front axle and prop shaft to allow full time four wheel drive. It is also a lot bulkier than the Series gearbox, and will involve modification to both cross members and floor/transmission tunnel/seatbox. The Fairey overdrive does not fit the LT95, but there are overdrives made for it. Whether they are necessary is less certain, as there are a variety of different high range gear sets for the LT95.

John

Geezer
8th February 2012, 08:53 AM
Obviously the V8 has been there a fair while, otherwise you'd have said something. Keep searching about gearbox numbers, as there is a fair amount of info on it. A little refresh of memory indicates that a SII box is not necessarily a problem. ( Which gear is not syncro? It may have been rebuilt to SIII specs.) The V8/series conversion generally twists propshafts.


I brought this series III as an unfinished project, actually it was two series III's one complete and the other a restored chassis with all its dis-assembled parts in a pile next to it, except engine & gearbox. I'm hoping to make a good one out of the two.
The complete one is not running as one of the welsh plugs has corroded and coolant pours out of it, plus the starter will not work. I have just removed the starter and about to test its operation on the bench (any suggestions here, most welcome). I have no idea which gears are syncro'd or not, can this be tested without splitting from engine?
It does have a Salisbury diff though, about the only thing I know will be up for the job! Gearbox work is new to me other than replacing a clutch, so please excuse my lack of experience here.

Does the R380 bolt straight on? I have a Lake adaptor plate if that helps.

Geezer
8th February 2012, 09:13 AM
I am not up on gearbox numbers, but from the clutch arrangement, it is a Series 3 box (although this is not definitive - the bell housing etc can be swapped with some caveats).

The Series 3 box is usually considered a little more fragile than the later S2a boxes, although late ones are probably not very different.

However, neither of these boxes is usually considered to be strong enough for the V8, and the Fairy overdrive definitely is not, although they will survive given sufficient care in driving.

The LT95 is certainly considered the strongest of the Rover gearboxes, but it is designed for full time four wheel drive, so to use it in a Series Landrover means modifications to the integral transfer case to allow part time four wheel drive or to the front axle and prop shaft to allow full time four wheel drive. It is also a lot bulkier than the Series gearbox, and will involve modification to both cross members and floor/transmission tunnel/seatbox. The Fairey overdrive does not fit the LT95, but there are overdrives made for it. Whether they are necessary is less certain, as there are a variety of different high range gear sets for the LT95.

John

I thought it was a series III gearbox to start with too, because of the clutch slave cylinder mounted horizontally on passenger side. But like you said the bell housing may have been swapped. I only started to think otherwise by the serial number suffix A which seems to suggest an early series II gearbox. I have only come to this conclusion from unconfirmed info off the net, hence, why I was hoping for help here from those with way much more experience than me:D
The problem with these type of rebuilds, is knowing exactly what parts you have to restore, however, you learn so much in the research trail.....
My last restoration, a mini moke, I didn't have the internet!!

Lotz-A-Landies
8th February 2012, 01:24 PM
Firstly a 9 prefix sequence number (8 digits) is SIII and SII gearbox numbers will have 9 digits and no suffix.
Secondly it has a SIII bellhousing, so while they can be fitted to SIIa boxes they can only be fitted to suffix B or later layshafts.
It is very easy to tell, drive it down the driveway and if it's synchromesh in 1st and 2nd its SIII.

The Suffix D series box is stronger than the rest of the S1 and SII gearbox because of the shouldered layshaft, larger layshaft bearings and larger intermediate shaft in the transfer box, but, of course, some (not all) of these modifications were in earlier suffixes.

The SIII layshaft cluster is stronger than the SII/SIIa splined layshaft, but the Suffix A SIII had a reputation of throwing the reverse idler through the case and all SIII boxes suffer from the very narrow size of the 1st and 2nd mainshaft gears.

The R380 has various models, assuming yours is a 4cyl, it is likely that you could get the short bellhousing R380 from a 200TDi Defender to fit in the space, but you either need to replace centre diff with the Santana or Ashcroft 2WD conversion or fit Stage 1 CVs to the front axle assembly.

Davo
8th February 2012, 01:53 PM
If you used any later gearbox, it will be meant for full-time 4wd. You don't just put Stage I CVs in the front axle, but you have to change the whole front axle to one from a Stage I, which is an easy swap, but expensive if you need to rebuild it. (I know - I did it on my SIIA.) A 2WD drive conversion would be easier.

If I were you, I'd do the basics to get the car actually driveable, and then see what you want to do with it. It's too easy to rebuild a car on the theory of what you think it will be like, and then not like it when it's done. (I know - I did that on my SIIA, too!) And then you start converting things, it can get really complicated. (I know - I'm doing that at the moment with my SIIA.) The V8 was used quite happily with Series gearboxes in the olden days, but with a very light right foot!

Lotz-A-Landies
8th February 2012, 02:12 PM
If you used any later gearbox, it will be meant for full-time 4wd. You don't just put Stage I CVs in the front axle, but you have to change the whole front axle to one from a Stage I, which is an easy swap, but expensive if you need to rebuild it. (I know - I did it on my SIIA.) A 2WD drive conversion would be easier. ... que?

Yes to fit the Stage 1 CVs you have to fit the stage 1 chrome swivel balls and Stage 1 stub axles. .

But you don't have to fit the 3.54:1 diffs, you don't have to fit the Stage 1 3" wide 11" brakes (same as 6 cyl), you can use the same swivel housing as on any SIIa or SIII front end and you don't have to use the Stage 1 diff housing.

I know because I converted a SIIB to stage I CVs and swivels

Davo
8th February 2012, 05:38 PM
All true, but since we're talking about a full-time 4wd gearbox that would lead to the use of a Stage I front axle, I would be inclined to use the axle housing that points the diff nose up at the gearbox, and to use the double-cardon joint on the front driveshaft as well. I think it's one area where the factory really put the effort into getting it right instead of just changing a few bits and putting up with the subsequent vibrations from the full-time drive.

Also, if you're replacing the stub axles to suit the CVs, then you're going to replace the hubs to suit the stub axles, since they are the later ones with both inner and outer wheelbearing the same. (And if you're going to do that, then you should get some oil catchers and put them in - I did, and they do the trick when a hub leaks.)

But with a V8 you'd probably want the 3:54 diff anyway. And an upgrade to the brakes to what the factory did with the last of the 88" SIIIs, though, if it's a SII we're starting with, then with the later hubs with the bigger wheel studs they'll need the SIII drums anyway.

P.S. No, there's no hope for you, Geezer! Not if you've already restored a Moke. :p

Geezer
6th March 2012, 09:26 AM
Thanks all for your help and advice here, although a little confused :p
I haven't had chance to do any work on it lately to see exactly what I have to play with, and what may need to be identified and possibly upgraded. A part of me agree's with the put it back together with what I have and see how it goes, but I dont want to pulling it apart again in a month because the parts I've got don't match, wasting cash and time, both of which I'm poor.
I did get the v8 engine running though with some minor temp repairs to see what condition the engine was in after sitting still for several years in someones shed.
It blew no smoke and was very quiet much to my surprise :o although there is oil all over the engine so will probably have to strip down and replace gaskets and seals etc.. but hopefully no major ticket item costs.

Lotz-A-Landies
6th March 2012, 09:54 AM
Hi geezer

The box you have has a SIII number, so likely a SIII box.

The SIII a suffix were the weakest of the SIII boxes, especially in the case over the reverse idler.

I ran a 253 V8 on a suffix H SIIa gearbox for a number of years without any breakages. Probably because in the V8 you can idle up obstacles that others have to put the boot in and that is when you break things.

In a SIII box the 1st and 2nd gear are quite narrow and therefore susceptable to failure, so if that's what you have drive carefully in 1st and 2nd gear. In fact there may be times when its preferable to use 3rd and 4th low range instead of 1st and 2nd hi range.

Diana