Series III transmissions

[msggunny]

Are there better years/suffix's for the SIII transmissions?

I have 2 right now, one from a 72 (NADA) and one from a 77.

Con: The 77 has a clacking noise in reverse so i am assuming i have a chipped tooth on the reverse gear. Nothing horrible but noticeable.

Pro: the 72 is attached to the Tcase and in the galvi chassis i am using so it will be less work to just keep it all together and only have to swap the engine out.

Con: i have no idea on the actual condition of the 72. The PO said it was fine when he parked it 8 years ago and it doesnt drive now.

Pro: the 77 has a new 3/4th gear in it.

How hard is it to replace the reverse gear?

Thanks.

[yorker]

What is the suffix on them?

[msggunny]

What is the suffix on them?

Ha, i was trying to not have to find it.

Will let you all know when i get around to it. The 72 is torn apart so thats not an issue, the 77 is under a cover at the moment so maybe next weekend.

[yorker]

Well FWIW the first all syncro Series III transmissions weren't the strongest and are probably where the old "IIa transmissions are stronger than series III transmissions are" myth came from. I'm not really sure what improvements they had made by '77 though.

[yorker]

http://forum.landrovernet.com/showthread.php/202289-Series-III-Gearboxes-Which-Suffix-is-Best


Re: Series III Gearboxes, Which Suffix is 'Best'
The Camino web browser won't let me see the photos in full size - the page gets darkened, but the photo box doesn't open, so I can't see the detail of your pictures.

Suffix D and later boxes are the best. Most Sffix A gear boxes rebuilt by LR would have been rebuilt to later spec, mine being rebuilt to Suffix E. The way you can tell is by looking at the lay shaft and the 3rd and 4th gear synchro teeth.

Suffix C and later gear boxes have a "C" stamped on the lay shaft and have a radiused step near the aft bearing. Suffix D and later boxes have coffin shaped teeth on the 3rd/4th synchro hub and the corresponding teeth inside the 3rd gear and primary pinion have recessed sides, while C and earlier boxes have plain teeth on the hub, gear and pinion.

Suffix A boxes had the worst of the revers idlers. They were redesigned for later suffixes, but that involved changing the dimensions of the idler shaft and thus its holes in the casing, so it's not possible to fit later suffix reverse gears and shafts to a Suffix A box, but the gear was redesigned for reconditioning of Suffix A boxes to last longer. It still uses a plain bush rather than needle bearings, but gets around the worst of the wear, so rebuilding a Suffix A box is still a reasonable proposition if most of the parts are good. www.nickslandrover.co.uk