cav551:
The most common problem I recall was the high/low range synchroniser would break one of the pegs, after that it would be that it simply wore out so that there was a loud crashing on engagement, if that was left too long then the auxiliary drive gear’s ■■■■■ pegs got burred over. Only other fault was the already mentioned bolts or circlip. The odd one that had a ham- fisted driver would burr the dog clutches making it a bit of a ■■■■■ to change gear cleanly.The Roadranger was a really good box which gave little trouble, which was more than could be said for the early Twin Splitters and the SAMT… modifications and problems with yes/no valves.
That’s jogged the old memory cells Cav, the boxes were stripped to replace the High/Low synchromesh. Also it reminds me that the Foden six wheeler I had would jump out of range laden on a hill, it was a reconditioned box from Smiths at Albrighton and they had it back under warranty. Interestingly they couldn’t replicate the fault unladen so accused me of not changing gear properly…whatever they eventually found cured it though 
Always the driver’s fault eh! 
The original box that it replaced would stay in gear even with the lever in neutral, scary at times when parking on the weighbridge etc! 
Pete.