Hi Guys

The Limited Slip rear diff on my 2003 4.8 is shuddering/scraping when turning. I've done lots of research but now am confused by the varying info available. After reading lots of info I currently have a bottle of engine flush in there which I'll leave for a while and then replace with the correct oil. The problem is, what is the correct oil and how much do I need? According to the VIN plate, it is a HG35 diff. I've read that I need 140 LSD oil, but it's nearly impossible it get it here in the UK. The best alternative is 75-140.... Is that ok? and if so, which one? http://www.opieoils.co.uk/c-970-limited-slip-diff.aspx
And how many litres do I need for a limited slip HG35?

Many thanks in advance!

Nick