This chick wanted a nice car and.... Well read more...

[jimmy57]

Speedometer on dash is fed via the CAN from ABS control module and as I understood it the TCM uses the VSS off the transmission case for primary shift control. The CAN speed signals for left and right wheels are used as a go/no go decision as a difference between those two means you a re turning and torque steer will be worse if a shift occurs then.
There is one failure type where the planetary final drive set in the RH end of trans close to where the VSS is located has a failure and metal will contaminate the VSS.
Remove the VSS (pictured in the link in post above) and see if it has metal "fuzz" on it.
DO you know the fault codes from your car? Has the car been scanned for codes in every module by a capable tool?

[chipmunkbug]

I do have the codes. I have also found the equivelant meaning in what I call the volvo DTCs:
P1618 (ECM-530D) - Mechanic said it was a speed sensor (according to identifix.com)
P0751 (TCM-000B) - Shift solenoid A performance stuck off/ 1-2 solenoid valve performance
P0117 (ECM-2000) - Engine coolant temperature low input
P1330 (ECM-640F) - Camshaft Actuator? (Couldn't find clear definition)
P0010 (ECM-6400) - Camshaft position actuator circuit

According to the papers the mechanic gave me, the p1330 and p0010 are related and the fix lies in fixing the camshaft reset valve or the like. Also, according to https://www.matthewsvolvosite.com/forums ... 11&t=18091, p1618 and p0751 are typical of a speed sensor malfunction. (Hence the reason I asked about the speed sensor.) The mechanic also gave me a printout of p1618 problems in other volvos and others have replaced the VSS and wheel sensors.

What do you think? Am I on to something here?

PS I will look at the VSS this Saturday.

[jimmy57]

530d is the code that says there is a fault in the TCM that requires the emissions malfunction indicator lamp, MIL or what most call check engine light, to be lit. The code(s) in the TCM Is the damning one. There are pressure switches on a cover on valve body and the TCM can diagnose solenoid issues by comaprison of the solenoid control and the expected on or off signal from switch.
You probably have a solenoid that is sticking and not changing position for the 3rd shift. Is the fluid nasty or gray?

[chipmunkbug]

I changed the fluid and filter and yes, the fluid looked terrible and there was a massive buildup of metal on the magnet.

[chipmunkbug]

The solenoid will change to third, idk about 4th, when it is cold. What does that mean?

[dcarlson12]

What does 'idk' mean? Or is it a typo?

[chipmunkbug]

sorry. I am typing on my phone. Idk means I don't know.

[jimmy57]

Given the metal on pan magnet your trans is likely misbehaving due to a failure that lets fluid leak out of seals. When bushings supporting rotating clutch drums fail the piston ring type seals will not seal the bore to the journal where the fluid feed holes are located. No way to know without a teardown but the prognosis is not good that solenoids or any external fix will do any good.