I have been experiencing some disturbing downshift problems with my 850 Turbo automatic. After a hard run, the tranny will downshift late when shifting down to second and first gear from fourth. This oftentimes results in the final downshift occurring after the car has completely stopped, although it sometimes occurs after I push on the accelerator to leave a stoplight. The effect is most pronounced in "sport" mode, less so on "econo" mode and does not seem to happen when I run in 3 speed mode. I also have experienced hard shifting to reverse right after this happens (maneuvering for a parking space, etc). I had the tranny power-flushed a couple of thousand miles ago with Volvo fluid, so it seems unlikely that it is the fluid (which looks pretty good when I inspect it on a white rag). Also, there are no error codes showing up (verified by the local Volvo dealer). I could definitely use some help from the transmission experts on this board to diagnose this problem. I have been seriously considering some performance upgrades that will presumably increase the HP output of the engine, but I am loathe to go too much farther until I know the nature of the transmission problems-more HP could be the proverbial straw that breaks the tranny's back. Thanks in advance.
850 Turbo Downshift Problems
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Well, the tranny is the weak point on this car. We had rough shifts, not as bad as you, on our 850R. I replaced the fluid with synthetic and it cleared up the problem. I hope yours is that easy, but since you already replaced the fluid, that is a concern.
George,
Thanks for the reply. I have not yet tried synthetic fluid, so maybe another flush/replace with synthetic will help. BTW, which brand did you use, and did you experience any seal leakage? THe local Volvo service manager recommended against synthetic tranny fluid because of the potential for leakage, but others have apparently had success with this upgrade.
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I had my garage do it, so I'll have to check on the brand. We don't have any leakage, but the car is only at 52K miles, so I wasn't really expecting anything anyway.
The deal on leaking is general to all synthetics. If you have leaks, synthetic tends to leak worse. I've heard that same story with synthetic motor oils. Is yours leaking?
The deal on leaking is general to all synthetics. If you have leaks, synthetic tends to leak worse. I've heard that same story with synthetic motor oils. Is yours leaking?
Leaking is one problem that I DO NOT have, so I may take a chance on synthetic with the knowledge that I can always put dino tranny fluid back in if I do get some leaks. OTOH, a minor leak would be much preferable to the rough shifting, but I hope it doesn't come to that kind of trade.
Thanks to all for the feedback-I will be doing my own flush sometime in the next few weekends, using a manual method I saw on OzBricks. I might be able to get the local Volvo service manager to give me a good deal on the flush (with my own fluid), in which case I will forgo the manual method in the interests of speed and convenience. Next question: is there any specific type of synthetic ATF I need to use, or is it pretty much "one size fits all"? Mobil has a Dexron III/Mercon synthetic fluid-since the manual lists Dexron IIE or Mercon, this would look to be compatible. Anyone have any specific recommendations?
I flushed the tranny last weekend with Mobil 1, using the recently updated Ozbrick/Volvospeed Bay 13 method (flushing the old fluid out via the upper tranny cooler hose). I used a total of 10 quarts, plus 10 oz. of Lubegard ATF protectant. The fluid that came out at first was pretty cloudy and more brown than red, but not as bad as the first flush (very dark brown then). By the 8th quart, the tube showed a consistent "cherry cough syrup red" colored fluid, so I flushed two more through and then added the Lubegard. Using the transmission pump was pretty painless, although I was a bit worried at first that I would not be able to shut off the motor in time to avoid damaging the tranny. I marked 2 qt. increments on an old drywall bucket (dont remember where I got that tip from), and that help time the on/off motor control quite a bit.
As for performance, so far, so good. I have only noticed one or two instances of semi-rough shifting (up or down), and the overall shifting performance has ben much smoother. Shift transitions are smoother both ways, and the banging when going from fwd to reverse has lessened dramatically. I also installed new Powerstop crossdrilled front and rear rotors (with Axxis Metal Master pads), so I have been babying the car a bit during the 200 mi (?!) break-in period recommended by Powerstop, so that may account for SOME of the smoother shifting!
My final weekend tweak was to diddle with the turbo boost setting (+3 turns), which made a much bigger difference than I had expected-the car was noticeably quicker off the line. Next stop-exhaust, then a chip upgrade. I might try to sandwich in a Dynaudio speaker upgrade along the way! 1 - 9 of 9 Posts
