Harsh downshifts

You need to see whether your transmission is of the "lifetime fill" or regular variety. However, in any case, there have been service updates published by both ZF and Mercedes (the two main auto transmission manufactuers along with GM), that an oil change is recomended at around 60k miles or 100k km for the lifetime fill varieties. This recommendation is due to the carbon particles leaching out of the (now, non-asbestos) brake bands and somewhat contaminating the oil.

I might be inclinded to see if there's any change in reverting back to the original ECU chips. There is supposed to be communication between the engine and gearbox with signals to momentarily reduce engine power during gear-changes.

However, given the mileage, I would not discount the possibility that a gearbox overhaul may be required.

Oil in 4HP boxes needs to be changed every 2nd inspection 2
This means that in general an exchange occurs between 50 and 60k mls

5HP boxes in the M60/62 and M73 are different... or so they say. Those, according to BMW, need no regular flush within a "lifetime", only they forgot to tell what their definition of lifetime is. ZF the manufacturer recommends changing the ATF fluid around 150k kms or 90k mls.

Cheers
Reinhard

Hi Nick,

I don't understand what you mean by 'down shift'.

My solution to this it to try not to back off until the transmission have shifted. When you shift while applying throttle, the ECU takes the ignition back a bit giving you a smoother shift. When you change the throttle position, this is harder / cannot be done in the time it shifts, and therefore you get a hard clunk.

My 2 cents.

I have changed all of the fluids in mine and particularly the gear box irrispective of the recomendations.

I seem to remember a hard kick up under accelaration back off - slightly miss timed - I have not installed Wokke Chips yet and so I have no opinion about them.

I would suggest an oil change as it never does any harm, and see how it goes

My 2c

Whilst not exactly the same problem, I thought it might be appropriate to post it here as it relates to the StepTronic gearbox.

I have an E53 4.4i Sports. This has a similar engine and gearbox to the E31. I am finding that in Sports mode, the gearbox doesn't automatically change up a gear when the revs have hit maximum (which it does do in the E31and should do in the E53).

After a reasonable length run, I am also finding it stays in the lower gear and won't change up when in auto mode. So I am doing 30 mph at 4,000 revs.

I'm hoping (fingers crossed) that it's something like "change the oil", rather than your gearbox is "fu**ed"!

Any ideas, guys?

On the facelift 740i E38 (which has the same drivetrain), this can be caused by a faulty camshaft sensor - yes, I know it sounds strange, but that is the usual cause! I would suggest diagnostics on the box and engine to start with (INPA is good for this).

Hi Tim,
Where's the best source for getting hold of INPA?

I can't find bmwteq on Ebay now, he was offering the kit and would also talk you through the installation - still, there are loads of other sellers on there. You will also need the OBDII to round-BMW connector adaptor. Something like this should do:

http://www.ebay.co.uk/itm/BMW-…m19c8b11b2a#ht_2028wt_829

Hi Timm,

I was checking out the BMW INPA EDIABAS INTERFACE INC FULL SOFTWARE FROM UK your link takes you to. So, for £25 and a laptop, you have diagnostic capabilities? Seems to ggod to be true?

Ivan

Zitat von IvanT;92428

I was checking out the BMW INPA EDIABAS INTERFACE INC FULL SOFTWARE FROM UK your link takes you to. So, for £25 and a laptop, you have diagnostic capabilities? Seems to ggod to be true?

BMW applications like DIS and Ediabas/INPA are not available to end users. It's quite safe to say that every copy you see for sale or for download is illegal...