Gearbox problems, slipping out of top gear when hot

[alan.c.hughes]

Hi All, Not sure if anyone will read this now as I'm sure your all having a great time at the bongo bash (we're planning to come sunday for the day hopefully !)

Anyway my Bongo runs great and drives great while it's cold but when it gets hot after 20 miles or so it seems to slip out of top gear when I'm cruising along the motorway for no reason. It's like it kicks down. Looked at some posts and I don't think my speedo has been chipped as the ODO is still in KM so I guess it's had a new face put on the speedo (?).

Is this a common problem, any ideas ??

Thanks for any help.....

[missfixit70]

Have you checked the level in the prescribed manner & is the ATF looking & smelling ok? Has it been renewd to your knowledge? if not it may be worthwhile draining, cleaning the filter & refilling, that seems to have solved a few autobox problems.

[astrobyker]

When this happens do you get a flashing Hold Light?

Jes

[Steve L]

Alan,
Is your Bongo performing well? I drove mine at around 60 to 65mph since I got it for the sake of fuel consumption so didn't notice any drop in performance. Then mine started changing down for no reason. I floored the accellerator but could not get any more than 70 to 80mph out of it. I changed my fuel filter and cleaned the gauze filter under the banjo bolt on the fuel pump and it solved the problem. Now performs better than ever.
My theory is that this behaviour is nothing to do with the gearbox itself, but a problem of fuel starvation. If the filters are blocked then you need to press the accellerator down further than you normally need, to get the required amount of fuel to the engine. This makes the gearbox think its in kickdown mode and so changes down.
I'd check the gauze filter first (cos its the cheapest).
But check the auto box fluid just in case.

[alan.c.hughes]

Thanks for your suggestions. I've not noticed the hold light flickering and certianly the performance seems excellent in accelleration (and she starts first turn every time), cruising is OK at 70-80 and my wife reckons it goes up to 90 OK .
It needs a service soon so I'll get them to check the ATF and filters (I think it's had a new fuel filter recently). Hopefully it sounds like nothig too serious (famous last words !!).

Cheers,

Al