2004 V70R auto 3rd gear sometimes dropping

nofro · Post by **nofro** » 29 Apr 2019, 11:57

I have a pretty new-to-me 2004 V70R with an automatic transmission, getting close to 190k miles. Ive been looking on this site since before purchasing the car and it has been a great resource. Hopefully someone here can help with diagnose a tranny issue I've been having.

The problem: A few months ago I noticed that sometime when slowing down to make a turn, when I hit the gas to accelerate it would drop out of gear as if in neutral, then slam back into gear.

I tried flushing the fluid (which was pretty brown) and changed the servo cover while I was at it. Not much (if any) effect.

I began driving in GT mode, manually shifting. This worked pretty well to avoid the downshifting/drop down from the auto and was almost able to avoid the issue altogether, but I found out a little more:

-Most of the time, all gears behave normally
-It drops to neutral without changing gears, with the selector in 3rd gear (or when it downshift as initially discovered)
-It happens when accelerating from a relatively low speed (low rpm) in 3rd gear
-It can happen at just about any amount of throttle, and catches the gear again when let off the gas
-It seems like it might be related to whatever changes are happening in the transmission as the torque converter locks/unlocks around that rpm range, but I'm not really sure what the trans is doing there.

If anyone has any ideas or experience with this, I would appreciate the help. Thanks!

Post by **RickHaleParker** » 29 Apr 2019, 13:38

Exact symptoms of the B4 servo cover issue.
The B4 Servo issues usually does not affect 2004 and newer models but it is not unheard of.
$30.00 in parts and you can change the B4 Servo cover without pulling the transmission.

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nofro · Post by **nofro** » 29 Apr 2019, 13:45

That's the best I could figure, so I changed the servo cover and flushed the fluid already but there was no improvement

Post by **RickHaleParker** » 29 Apr 2019, 15:10

There where a number of software updates to fix shifting issues. It does not cost anything to talk to a Volvo Dealer. If your lucky, they might cut you a good deal if the software needs updated.