I've joined this forum in the hope that someone can help. We have a Thwaites Alldrive articulated 4X4 dumper, powerd by a 3 cylinder Lister electric start engine. We've always believed it to be a 7000 series, but when enquiring about gearbox parts from David Cornwallis, he reckons it's older than that as it is fitted with a Newage F4R2, 4 speed (Forward and reverse) gearbox. This is the type with 2 gear levers. It runs a Disc transmission brake. David sent me an exploded diagram of a box fitted to a Thwaites 6000Mk2, but this is not the gearbox as ours has a full size removable "lid" and runs a drum brake. When questioned, David said that it's "even older than he thought" and that he was unable to supply any parts. We are looking to find all bearings and seals in order to rebuild this box, but would consider a second hand box if one were available, as our has a couple of gears that are in poor condition. The plate on the lid of the box says Newage F4R2, s/no 3458, (there could be an extra figure at the start of the S/No as the plate is damaged). Embossed on the box lid is : F4R102. Has anyone got any suggestions where to try? Anyone have an exploded diagram of this box?
We are also looking to replace the "articulation" pivot pins/bearings. In order to identify the model of the dumper I will take some photos of the entire machine in the next few days. Now to try and upload photos of the gearbox casing!
my suggestion would be that bearings and seals would be available from a local bearing/drives supplier; bearings are usually pretty much standard 'off the shelf' items as are seals, simply take your worn part along as a sample and where possible if the bearings/seals have disintegrated altogether take the bore size and the outer diameter size they should be able to fix you up with something. 
