Re: Life of a Shogun?


"Tim.." <the.farm.no@xxxxxxxxxxxxxxxxxxx> wrote in message
news:W8qdndMc7v_uVFfbnZ2dnUVZ8q6unZ2d@xxxxxxxxx

"Dave Plowman (News)" <dave@xxxxxxxxxxxxxxx> wrote in message
news:4f15ce0a1cdave@xxxxxxxxxxxxxxxxxx
In article <Xns999376E8FAD21adrianachapmanfreeis@xxxxxxxxxxxxxxx>,
Adrian <toomany2cvs@xxxxxxxxx> wrote:
A *good* slushbox will have a very long life. Trouble is knowing which
ones are good - and it doesn't just go by maker.

Indeed. It seems to be all about the detail design of the installation -
some installations get the cooling and/or service intervals badly
wrong, resulting in predictably short lives. Even those can often be
prolonged by ignoring the fluid change intervals and changing more
regularly - every engine oil change, p'raps.

Cooling certainly is important. I'm not convinced that regular fluid
changes would help - the fluid shouldn't get contaminated. Once that
starts the box is failing. The other thing is you can't easily change all
the fluid as the torque convertor can't be drained and holds something
like half the total.
If you have an external cooler you can sort of flush through all the
fluid by bleeding it out with the engine running while introducing new -
but that's a pretty expensive method. On 'lifetime fill' boxes probably
worth doing at about 80,000 miles.

Fresh fluid is important in my experience- the anti wear and friction
reducers etc etc of the fluid break down with time, and especially heat.

I deal with many comercial and agricultural TC 'boxes, and those that have
been run hot (typically silage pit work etc) and where cooling is marginal
always die first. Anything over prolonged 80deg C work kills them. In many
cases the brake bands are glued and much hotter than this and they start
to un-glue themselves!

Tim..

Yes, spot on. It doesn't matter that only a proportion is changed because
that is factored into the interval. The reason for changing is indeed to top
up the additive that gives the total fluid its various qualities. And yes
heat kills the linings which are mostly a thin cardboard laminated onto
steel backing. Wet brakes can be killed almost within a minute or so if
starved of cooling oil.

Huw


.