Diagnosing gearbox issue

[thruflo]

Hi all,

We have a 2000 Bongo V6 automatic, converted in the UK in 2020. I believe it's having gearbox or transmission problems. We're in Europe now and the local mechanics aren't very familiar with Bongos. So I wondered if I could ask for advice on identifying the problem and potential fixes.

Basically symptoms are:

- a persistent electric motor whining noise when driving with the accelerator pressed, especially uphill, stops when you relax the foot off the accelerator, comes back on when you press down again; does go away sometimes, especially after driving for a while
- a feeling like the van isn't as powerful as it used to be -- used to eat up hills, now needs to be kicked down a gear to feel any power
- occasionally also hold coming on and sticking in a low gear when driving down the motorway [not sure if this is related or just a sticky button on the gearstick]

Does this sound like a common problem? Any advice or pointers?

I've seen the FAQ on auto gearbox problems https://www.igmaynard.co.uk/bongo/forum ... hp?t=74445 -- I'm guessing should start with those steps, e.g.: check transmission fluid, drain fuel, check crank shaft sensors, check gearbox plug wiring, but as a car/van maintenance newbie I'd love any pointers or perhaps specific things I can ask a local mechanic to take a look at for us.

Thanks,

James

[g8dhe]

Yes use the checklist in the Factsheets area and make sure you check the ATF the correct way (In gear, running & warmed up) you will need to dip the level several times as its normally splashing around inside. Should be a nice translucent red colour, if its smelling and very dark then as a minimum you need to drop as much ATF as possible (a significant amount will be trapped in the TC).