Hi All,

MY 2007 TDV8 has done 75K so when I first got it I had the garage do an oil flush on the ZF gearbox.

I did not drive it much before this so have no point of reference. The gear box seems to change smoothly however I have noticed that going from 3rd to 4th seems to take a little longer then 1st>2nd>3rd.... I would say the others are about one second to change whilst 3rd to 4th seems to take a little longer (perhaps 2 seconds) is this an indication of wear or is this normal.

I am thinking I might change the sump and filter myself. Also if there oil had been overfilled would this cause an issue (I only ask because I found that they had overfilled the engine oil by about a litre)... L322 2007 TDV8 3.6

So I checked with the garage who did the oil flush and they use Rockoil ATF D6 oil. Is this suitable for the ZF box ? L322 2007 TDV8 3.6

This is not the correct oil. I used genuine zf oil in mine. Not massively more expensive but it’s guaranteed to be right.

Thanks Wk52RR. L322 2007 TDV8 3.6

Chris1573 wrote:

So I checked with the garage who did the oil flush and they use Rockoil ATF D6 oil. Is this suitable for the ZF box ?

Did they also change the valve body seal?

Obvious things are to ensure the filter is changed, there is not too little or too much oil, correct grade of oil and the valve body seal is replaced (along with the mechatromic sleeve) and also add an additive such as LubeGuard. So long as the oil used complies with 1375.4 or is classified as a Lifeguard 6 oil then, it really doesn't matter which you use - that's the whole reason oil standards exist.

The above should smooth out most common issues with a first gen 6HP26. You can also meter and induce the gear changes yourself - if you back off the throttle momentarily, you will trigger the gearbox to change.

You'll know if it's not right or not, as you're the one driving the car. The cars are ageing now and mieages creeping up and, worn valves and solenoids are to be expected.

If it's only a minor thing then, it's likely the gearbox will outlive other major components. If you know it's not right, take a look at this forum page on any partial re-build you may need. It's on a BMW but, it's a 6HP26 gearbox. Don't be afraid of any work that may be needed - replacing the mechatronics pack will solve most people's issues and is an easy job or, you can perform a partial re-build and save a load of cash.

https://www.bimmerfest.com/threads/zf-6hp-...y.1341849/

My car has done 150k. All gear changes are nice and quick. I was sometimes getting the odd harsh change - an oil and filter change and additive stopped that.

“ Did they also change the valve body seal? ”

Which seal are you referring to Gary?. L322 2007 TDV8 3.6

There is only one valve body seal. It's inside the gearbox above the mechatromics pack. It looks like this:

OK Did the filter and oil change and it does feel a bit better, took over 5 litres of the lifeguard 6 oil.

Plan is to get the seal kit and do this in a few hundred miles along with another oil change...

Oil pan was clean with just a slight amount of grey sludge on the magnets. L322 2007 TDV8 3.6

Worst case, you're looking at a mechatronics pack repair or replacement. Neither are expensive to do.