Hi steve
Lexus technition did say its the first he had seen, the only thing i can think of is about 18 months ago i went thru a flood and may have picked up grit, he also said that they do need to be blown out regular,
I did try and get the driveshaft reconedtioned but they sent it back saying that they had not seen one like this before that you could not strip down and reconditioned, i also tried to get ABS ring as they are only sweeted on but no joy, also tried CV joints off e bay gave them my engine/ vin/ and id/ and reg, had 2 sets which i still have stating they are for my car but they where to small, also bought 2 driveshaft off a scrappy but they was as bad as mine was? and still have those in my shed,at the end after months of trying and money waisted had new driveshaft fitted by LEXUS £580.
I drove around for months as it was on traditional brakes, all i can say to all reading is- when i braked it was fine but when coming to the final stop the ABS under bonnet was clicking like a relay clicking and no lights on dash, it was only when i took it for a service at my local garage and ased them to check it out for me which they must have made it worse as that it when the lights on dash came on, and this is when i waisted my time and money on trying to relace parts, LEXUS technition did say also that the mk1 and mk3 most parts are serviceable unlike the mk2 most parts are LEXUS only, i hope this post will help someone as i spent money waisted- secondhand driveshafts £100/ 2sets of cv jounts £120/ as i have said these parts i still have which i need to try and get rid of