Ecosse911

Hi

I am not a regular in this forum but want to help out a neighbor who has a 996 Tip. He just had it towed to a shop as the car was stuttering and then the check engine light illuminated.

Shop says it needs a new tranny due to P0740 code. The cheapest option they say is a refurb unit $5K and $1.5K labor.

Does this sound like a fair diagnosis and repair cost? Any other options?

Thanks

Joel987

What year is the car? Up to 2001 996 had ZF automatics. 2002 and up they have 722.6 Mercedes transmissions. If the latter there should be plenty of parts available as the tranny internals are used in several Mercedes, Chrysler and Jeep models. Labor sounds right as the engine and tranny come out together. Some here stated they removed the tiptronic with the engine in place, but my Indy couldn't do it after a few hours of trying and ended up dropping the whole drivetrain. Once on the ground it's fairly easy to separate the transmission. Of course with the engine on the ground there are all the "while you have access to" things to replace. What is refurbed in the transmission other than filter and fluid for $5k? Your friend may be better off finding a transmission shop that can rebuild his tranny.

Ecosse911

It’s a 1999.. I appreciate the feed back, I’m just trying to help him out, seeing as I don’t know anything about the 996 I said I would reach out to Rennlist crowd. It’s a shame as he recently started to refresh some items such as redoing the seats. Now he wonders if he should just sell the car as a parts car. Makes me sad

Gdjsk

Did u find solution sir ?

Porschetech3

The code P0740 on the 996.1 cars ( which all have the ZF 5hp19 trans) is caused by the valve body not controlling the fluid pressure, then extremely high pressure is sent to the lock-up converter which blows the rubber seal/o-ring, then the clutch begins to slip.. that sets the code P0740...

The fix is a new/remaned valve body and torque converter ..

BUT most shops either will not work on Tiptronics, or they will only warranty it if you do the whole ball of wax....ie " full rebuild"....

Of course if you DIY it, you can fix it the way you want, and if there is nothing wrong with the rest of the Trans...( ie no broken parts or big debris in the pan) it can be a rewarding decision...

Gdjsk

thankyou for replaying, in my case transmission fluid got mixed with coolant, after replacing gasketfilter, oil cooler, cleaning everything inside gearbox including removing torque converter & removing old fluid. Flushing around 6 times, now PNRD shifting while car is in lift, but as soon as we put the car down, it shifts but only reverse working, drive does not work, even if i accelerate car is not able to move.
I got fault P0740 & gear set moniter fault code for gear 4 & 2.
thankyou for replaying .

Porschetech3

If both gear 4 and 2 are "ON" at the same time, the car will not move . That is essentially what a "trans brake " does in Drag Racing , it applys 2 gears at once ( 1st and 2nd) then releases 2nd gear for the "launch" ...

Sound like you need a Torque converter, valve body, and maybe a 4th and 2nd gear solenoid....