6 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 Tiptronic Valve Body Replacement
Leading reported evidence
Repair (which i now believe was unnecessary)
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
Whole gearbox has been out twice in 5 years, first to have transfer case seal changed,(before I bought it), then to have torque converter refurbished and lock up clutch in Valve body repaired (which I now believe was unnecessary).
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
That Merc 722.6 tr4ans is also used in the 996/997TT, you should check with the specialty tuners that are hopping up and modifying the Tips for them and see what they got..
Leading evidence: 'Repair (which i now believe was unnecessary)' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check with the specialty tuners' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
Whole gearbox has been out twice in 5 years, first to have transfer case seal changed,(before I bought it), then to have torque converter refurbished and lock up clutch in Valve body repaired (which I now believe was unnecessary).
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
When the Valve Body was worked on, I replaced the Conductor plate with a Genuine MB part as it was apart anyway.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
That Merc 722.6 tr4ans is also used in the 996/997TT, you should check with the specialty tuners that are hopping up and modifying the Tips for them and see what they got..
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
The Sonnax kit replaces the outer part of shuttle valves with new parts containing orings to take up this wear and increase pressure.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Check with the specialty tuners
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
That Merc 722.6 tr4ans is also used in the 996/997TT, you should check with the specialty tuners that are hopping up and modifying the Tips for them and see what they got..
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
Whole gearbox has been out twice in 5 years, first to have transfer case seal changed,(before I bought it), then to have torque converter refurbished and lock up clutch in Valve body repaired (which I now believe was unnecessary).
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed · Original poster
Whole gearbox has been out twice in 5 years, first to have transfer case seal changed,(before I bought it), then to have torque converter refurbished and lock up clutch in Valve body repaired (which I now believe was unnecessary).
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Just to be devil's advocate, but if Porsche only offers the "old" style valve body, then there will be no software to "reflash" the TCU...( I'm 99% positive you cannot use the Merc software on the Porsche TCU)
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
6 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T144035Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi Rennlisters
My first post so please be gentle. I love my 996 and its in great original condition except for one big problem.
It's a 2003 996 Carrera Tip with Gearbox Valve Body Issues. Long story short. Whole gearbox has been out twice in 5 years, first to have transfer case seal changed,(before I bought it), then to have torque converter refurbished and lock up clutch in Valve body repaired (which I now believe was unnecessary).
The Valve body has been out twice as well, first to fit Sonnax shift kit to stop very harsh shifting down the gears when gearbox hot, like dropping the clutch in a manual when changing down(this was an experiment, which kinda worked for almost 12 months but the harsh shifting returned) then to fit a re-manufactured Valve Body from Revmax, which ended badly with my original being reinstalled.
So, I'm looking far a brand new Valve Body. Its a Mercedes Benz part that is no longer produced P/N 140-270-02-06. They only sell the updated 140-270-05-06 which I'm told requires a TCU reflash, New 05-06 MB Valve Body is $900 USD.
Porsche P/N 722-270-02-06 is still sold but Porsche Australia want $3800 AUD for the Valve body. I've found it for $1800 USD. Still twice the identical MB Part.
So that's a brief background.
My question is: Whats the difference between the older and newer Valve Bodies and is it possible/how easy is it to reflash the TCU to accept the new one. Or has anyone had a new replacement fitted?
I'll share a few more fixes I've carried out later, (Clockspring, Bump Stops, Oil Pressure Gauge, Window Regulator, Throttle Body to name a few,) but this one is the current conundrum.
Thank in advance
SilverTip
I couldn't have got this far without Rennlisters advise, so thanks a million.
I don't have a tip but from what I have heard those benz auto tranny's are extremely reliable; I'd be picky about who I had working on it, the guy shop could do more harm than good.
Just to be devil's advocate, but if Porsche only offers the "old" style valve body, then there will be no software to "reflash" the TCU...( I'm 99% positive you cannot use the Merc software on the Porsche TCU)
That Merc 722.6 tr4ans is also used in the 996/997TT, you should check with the specialty tuners that are hopping up and modifying the Tips for them and see what they got..
The 722.6 is indeed rock solid mechanically.
Were there any fault codes in the TCU?
One of the most common problems over longer lifetime with the valve body is the conductor plate. It is plastic and will eventually brake down due to the exposure to heat (cycles).
What was refurbished in your original valve body? If not already replaced during refurbishment I would look at the conductor plate first and see if replacing it solves your problems.
Thanks for the replies guys.
When the Valve Body was worked on, I replaced the Conductor plate with a Genuine MB part as it was apart anyway.
No codes showing on the gearbox, just harsh shifting down the gears when warm.
The problem is within the Valve Body where the shuttle valves wear and score the bores, which allow pressure to leak past as I understand it.
The Sonnax kit replaces the outer part of shuttle valves with new parts containing orings to take up this wear and increase pressure.
This made downshifting better but not 100%, but over time has degraded. (only a few thousand kilometers meaning definitely scored bores chewing up the orings.)
I really need to know where I can source a new Mercedes Valve Body as they are a third of the price of Porsche ones and are identical.
All avenues I've tried so far have said discontinued and offered the new part number which means a reflash of TCU.
Anyone else have any ideas?
