Re: Life of a Shogun?

Dave Plowman (News) (dave@xxxxxxxxxxxxxxx) gurgled happily, sounding much
like they were saying :

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.

It gets cooked, and the lubricity breaks down.

The ZF 4HP18 in the Cit XM is a classic example - change the fluid
according to Cit's 36k recommendation using the drain hole (which only gets
one litre or so out), and wait for the box to die at 120k, regular as
clockwork.

Change it every 9k with the engine oil, or disconnect the cooler hoses to
get the lot out instead of just a bit, and it'll live damn near forever.

On 'lifetime fill' boxes probably worth doing at about 80,000 miles.

Indeed - Cit replaced the 4HP18 with a different box in the later 24v XMs -
"Sealed for life". They die at about 100k unless you change the fluid
regularly...
.