limited slip diff - working?

[andycook]

Wondering if the limited slip diff is working on my 30 TD 4runner.
It defintely has one, as when I jack-up the back axle and turn one wheel, the other rotates the same way.
But, when on wet tarmac and in 2WD and turning sharply into a junction, or going round mini-roundabout, there is some slip at back end, not sure if its wheel spin, but feels like a bit of sideways action.
The tyres are huge 255/75 r15's - with a chunky off-road tread, more aggressive than the BFGoodrich all-terrain TA, like mud-tyres

I am guessing its just a combination of non-suitable tyres and a heavy vehicle as I am more used to driving a subaru.
but I am also wondering if the incorrect oil has been put in the rear diff at some point

any feedback welcome

[Koi]

Wondering if the limited slip diff is working on my 30 TD 4runner.
It defintely has one, as when I jack-up the back axle and turn one wheel, the other rotates the same way.
But, when on wet tarmac and in 2WD and turning sharply into a junction, or going round mini-roundabout, there is some slip at back end, not sure if its wheel spin, but feels like a bit of sideways action.
The tyres are huge 255/75 r15's - with a chunky off-road tread, more aggressive than the BFGoodrich all-terrain TA, like mud-tyres

I am guessing its just a combination of non-suitable tyres and a heavy vehicle as I am more used to driving a subaru.
but I am also wondering if the incorrect oil has been put in the rear diff at some point

any feedback welcome

It will be the rear end slipping. Trouble is we have all been spoilt with front wheel drive motors, these motors do handle well but need respect.
When cornering keep it all smooth, don't lift off or push down the loud pedal, keep the steering smooth and clean. Don't suddenly turn in harder or alter the steering during the corner, keep it smooth and they are fine.
I have a Surf with 31 x 10.5 x 15 BFG MT's & a Runner with 275 x 60 x 17
General grabber AW, both handle fine if treated with respect as should all rear wheel drive motors. Drive and old Capri or the old 3.0 Granada then you will know about losing the back end.

[Elvz]

The clutch packs in Toyota LSD's only last about 50,000Km even if you service the diff regularly.

[Cmar]

190,000k on mine ('98 3.0 td intercooled) the diff dosent look like it's ever been apart and it's still working fine!

Nothing quite like the feeling of powersliding a Surf off a wet roundabout...

[TonyN]

A slippy back end is a sign the LSD is working. With an open diff, one wheel spins, and the other coasts, not driving but giving lateral stability as its not spinning and holding the truck straight.

A tight LSD will spin both wheels when given to much welly, it both rears are spinning, you'll get little side to side grip.