Tiptronic hard shift

[Najarro]

I have an Audi a8 with tiptronic gearbox (zf 6hp26) which had torque converter shudder. I updated the software and changed to the green atf used in Zf8hp gearbox and that problem is solved.
However, once I have changed the atf, I have a jerk shift from 1 to 2 and from 3 to 2 always when hot. When cold it is fine. Now in summer the shift is still worst.
I have been thinking in using lubegard atf protectant (red) which seems to be good for heat problems. I'm also thinking in improving the atf cooling, but don't know how to perform it. It has a small cooler which uses engine coolant.
Do you have any ideas or possible solutions for this problem?
Thanks

 

[Greasymechtech]

Recheck ATF level.

How many miles on new fluid?

Change engine thermostat and coolant.

 

[Olas]

To better control the harshness of shifting and selecting gears, you need a car with a manual gearbox and clutch pedal.

Left foot finesse makes for the smoothest drive known to man.

 

[Najarro]

Originally Posted By: Greasymechtech
Recheck ATF level.

How many miles on new fluid?

Change engine thermostat and coolant.


New fluid has 6000 miles

 

[Peter_M]

Originally Posted By: Najarro
I have an Audi a8 with tiptronic gearbox (zf 6hp26) which had torque converter shudder. I updated the software and changed to the green atf used in Zf8hp gearbox and that problem is solved.
However, once I have changed the atf, I have a jerk shift from 1 to 2 and from 3 to 2 always when hot. When cold it is fine. Now in summer the shift is still worst.
I have been thinking in using lubegard atf protectant (red) which seems to be good for heat problems. I'm also thinking in improving the atf cooling, but don't know how to perform it. It has a small cooler which uses engine coolant.
Do you have any ideas or possible solutions for this problem?
Thanks


Najarro,

Have you used the correct fluid? Isn't that fluid just for the W12 engine cars using that transmission?

http://www.zf.com/global/media/en_us/lubricantslists/TE-ML_11.pdf

Since the shift quality seems to deteriorate with temperature, it seems to viscosity related and may warrant a full flush with the correct fluid.

 

[Najarro]

[/quote]

Najarro,

Have you used the correct fluid? Isn't that fluid just for the W12 engine cars using that transmission?

http://www.zf.com/global/media/en_us/lubricantslists/TE-ML_11.pdf

Since the shift quality seems to deteriorate with temperature, it seems to viscosity related and may warrant a full flush with the correct fluid. [/quote]

There is a Technical service bulletin from audi which regards to use lifeguard 8 instead of lifeguard 6 when torque converter shudder happens, and performing an update for gearbox software. Here it is the TSB http://uberlame.com/a6_tsb/Transmission/Chirping,%20hooting,%20squeaking%20noise%20when%20shifting%20between%203-4.pdf

 

[BowNisPar]

Any chance of getting it in front of an Audi dealer to get their diagnosis/recommendation?

 

[Greasymechtech]

6k miles is enough for the transmission to adapt to the new fluid.

How many miles on vehicle and previous maintenance history on transmission?

Might be a worn out valvebody... VB is a term that some automakers don't like using... and they trademarked some fancy schmancy VB equivalents like Junkatronic, Failatronic, Bankruptowneratronic...

Hard shifts could also be TCM TCU failure.

 

[Najarro]

Originally Posted By: BowNisPar
Any chance of getting it in front of an Audi dealer to get their diagnosis/recommendation?


Yes, of course, but they say there is no fault code in ECU and then the only option for them is fitting a new gearbox for 9000€

Originally Posted By: Greasymechtech
6k miles is enough for the transmission to adapt to the new fluid.

How many miles on vehicle and previous maintenance history on transmission?

Might be a worn out valvebody... VB is a term that some automakers don't like using... and they trademarked some fancy schmancy VB equivalents like Junkatronic, Failatronic, Bankruptowneratronic...

Hard shifts could also be TCM TCU failure.






It has 86000 miles.
First atf change at 76000 miles (when i bought it) (original atf was black) using the specific lifeguard 6. I decided to change the atf due to tcc shudder. As it continued with shudder problems I read several forums and I found the TSB. The audi dealer updated the software and I changed the atf (green). This solved the shudder problems but now I have the hard shifts when hot.

The atf green I used is mannol atf ag60, which meets vw g060162 spec. I think the problem is that this atf has very low kinematic viscosity when hot (5-6,5 cst) and this is what causes the hard shifts.

 

[SatinSilver]

I had this issue on an Accord after the dealer changed the rear main seal. Took it back and they agreed with me. They did a drain and fill with atf and everything was fine for the next 80k. Which was when I sold it.

Maybe a metal particle came loose and has blocked a small internal passage of the trans. Esp if the old atf was old and a "flush" was done. Maybe try a drain and fill of the atf.

 

[Greasymechtech]

Try the Mannol AG55 and see if it helps.

 

[Najarro]

I've checked the level with engine running and it was too low. I need to drive it, I've just done 10 miles but I think the problem is solved.

 

[Ducman]

Originally Posted By: Greasymechtech
Might be a worn out valvebody... VB is a term that some automakers don't like using... and they trademarked some fancy schmancy VB equivalents like Junkatronic, Failatronic, Bankruptowneratronic...

Hard shifts could also be TCM TCU failure.






That's gold.

Thank you sir.

 

[Ducman]

Originally Posted By: Olas
To better control the harshness of shifting and selecting gears, you need a car with a manual gearbox and clutch pedal.

Left foot finesse makes for the smoothest drive known to man.


Agreed wholeheartedly.

But it doesn't fix the Op's issue.

A switch to a manual transmission might solve certain issues, but I'd hate to be advising what to do about variables regarding inconsistent syncho operation.

 

[CT8]

Originally Posted By: Greasymechtech
6k miles is enough for the transmission to adapt to the new fluid.

How many miles on vehicle and previous maintenance history on transmission?

Might be a worn out valvebody... VB is a term that some automakers don't like using... and they trademarked some fancy schmancy VB equivalents like Junkatronic, Failatronic, Bankruptowneratronic...

Hard shifts could also be TCM TCU failure.

fine German engineering.