Thread: What happened to your D3/D4 today?

There is actually a very specific drive cycle that is meant to be followed when resetting the gearbox adaptions to help it relearn a lot quicker.

Varies between ZF models but typically with the transmission warm at 60degC you apply the reset program then in drive (not sport) accelerate gently through the gears (~20-25% throttle) to 6th gear then with light brake application slowly decelerate to a stop. Wait 10secs and repeat cycle for 9 times.

Some transmission programs have a second procedure which involves repeated gentle acceleration and deceleration at speed with the transmission held in manual in 5th and 6th. This is done by accelerating with light throttle and then coasting without applying brakes from 60-90-60 kph in 5th for 4 times, then from 70-100-70 kph in 6th for 4 times, then slow down go back to 4th and repeat this cycle 5 times.

Then finally at a standstill shift between N to D to N to R to N waiting 5 seconds between each shift and repeat 5 times.

It varies between cars and the specific software program in use, plus the number of cycles for the first pattern can be different, but this is the general pattern for the 6HP26 transmissions in BMW’s from the same era as recommended by ZF.

Probably just adds 5-10km when new from the factory if the specific procedure is followed. Most new cars have 15-50km already driven when first delivered.

If there is a particular change which is still not smooth after doing the above then just do gentle changes in that gear in drive with ~20% throttle and it should relearn the correct solenoid settings after repeat shifts.

Originally Posted by Tombie

Pro gear 75-90 for the front Jeff ☺️
GL5 for the rear if you have an e-locker.

Given the small volume in the front I’d want the higher viscosity oil up front!

——-
thank you Tombie.
I will do the Front Diff again with the Pro Gear 75W-90.

WRT the D4 Rear Diff, mine is NOT an e-diff. Is the Penrite Pro Gear 75W-90 suitable for this version please?
thank you.
Best. Jeff.

Originally Posted by Jeffoir

——-
thank you Tombie.
I will do the Front Diff again with the Pro Gear 75W-90.

WRT the D4 Rear Diff, mine is NOT an e-diff. Is the Penrite Pro Gear 75W-90 suitable for this version please?
thank you.
Best. Jeff.

Yep 75-90 front and rear without eDiff

Busy night last night finishing off the front brakes.

HEL lines fitted, new 360mm rotors (mines 2.7 so normally 320mm) and callipers to suit.

Just cleaning up the workshop a bit today before I start the bleeding process and replace all the fluid in the system.

Few more things to do….

Originally Posted by DiscoDB

There is actually a very specific drive cycle that is meant to be followed when resetting the gearbox adaptions to help it relearn a lot quicker.

Varies between ZF models but typically with the transmission warm at 60degC you apply the reset program then in drive (not sport) accelerate gently through the gears (~20-25% throttle) to 6th gear then with light brake application slowly decelerate to a stop. Wait 10secs and repeat cycle for 5 times.

Some transmission programs have a second procedure which involves repeated gentle acceleration and deceleration at speed with the transmission held in manual in 5th and 6th. This is done by accelerating with light throttle and then coasting without applying brakes from 60-90-60 kph in 5th for 4 times, then from 70-100-70 kph in 6th for 4 times, then slow down go back to 4th and repeat this cycle 5 times.

Then finally at a standstill shift between N to D to N to R to N waiting 5 seconds between each shift and repeat 5 times.

It varies between cars and the specific software program in use, plus the number of cycles for the first pattern can be increased, but this is the general pattern for the 6HP26 transmissions in BMW’s from the same era as recommended by ZF.

Probably just adds 5-10km when new from the factory if the specific procedure is followed. Most new cars have 15-50km already driven when first delivered.

If there is a particular change which is still not smooth after doing the above then just do gentle changes in that gear in drive with ~20% throttle and it should relearn the correct solenoid settings after repeat shifts.

So if all this is required for a new transmission to work properly and all the electronics to work properly it should be completed by the mechanic doing the work as part of the job and part of the final test drive before hand over
how can any mechanic assure the work carried out is not correct without doing all of it?
simply he can not so therefore has not done the job in it’s entirety and to say it just neeeds to bed I is a lie and incorrect as I stated

Originally Posted by discomatt69

So if all this is required for a new transmission to work properly and all the electronics to work properly it should be completed by the mechanic doing the work as part of the job and part of the final test drive before hand over
how can any mechanic assure the work carried out is not correct without doing all of it?
simply he can not so therefore has not done the job in it’s entirety and to say it just neeeds to bed I is a lie and incorrect as I stated

Unfortunately neither JLR nor ZF have published a specific procedure for the D3/D4/RRS, and it doesn’t even get mentioned in the workshop manual, and so the only available published advise is to follow the IID gap tool procedure which is to just drive the vehicle normally after the adaptions have been reset and it will relearn over a longer distance. Just needs to be driven further and takes longer to fully relearn.

The BMW procedure published by ZF is here:

https://www.bimmerfest.com/attachmen...e-pdf.1086434/

And a nice picture of the first part which is common to all:

When I put the Gen zip kit through and replaced all solenoids, pump seals, new fluid etc, the Sonnax info provided in the kit gave similar guidelines.

I have very little experience with ZF 6hp tuning..... However...

As far as I'm aware with the Auto stuff I've personally done, adaptions work both ways.

If your box is worn, the adaptions will calculate slip time and correct it as best it can.

If the box suddenly improves (rebuild) it will also adapt back the other way.

If you get your box rebuilt, the mech should probably reset the adaptions, it will POSSIBLY be quicker to get adjusted to where it is needing to be.

If this is done, he should really test drive it for you for a couple hours @ $200 per HR, so that it's adjusted correctly when you get it back.

Not many owners would want to pay that, but realistically (literally) it's the only way to re learn.

If he doesn't reset it and doesn't drive it much, it'll be up to the owner to simply drive it and let it re learn.

That's how it's designed to operate.

Personally I'd possibly get the adaptions reset, but I wouldn't pay $400 to get it driven around.

Cheers
James