Noisy Differential + Fuel Economy

[ruston_pj]

Hi All,

I'm a new Previa owner, but not new to Toyota (have a Carina E as well).

Really pleased with the Previa we have just bought - 92 J plate, but the differential is noisy. A mechanic friend suggested Molyslip, which I have bought, but the packet says don't use it on a slip-differential.

My question is: does the Previa have a slip-diff?

My mate says that the diff is unlikely to fail - it will just stay noisy, or maybe get worse. Anyone changed one of these, and is it a hard/long job?

Fuel economy - we're getting about 26mpg on a run - which I think is about par for the course, but I'm wondering if anyone has improved it using Greased Lightning, Slick50 or other additives?

Cheers in advance for any help.