Greetings,
I recently purchased a 940 Volvo turbo Wagon. With the help of these forums and various other sources, I've been able to fix quite a few things on beauty without having much prior knowledge of cars.
Here's a list of things I've done in the past month or so.

Replaced Valve Cover Gasket.
Replaced Spark plugs.
Pulled out the instrument cluster and reflowed the solder joints which fixed my busted fuel gauge.
Replaced the just about all the hoses included the (fase hose?) that connects to the instrument cluster.
Replaced a busted heater control valve which blew on a trip back from Seattle WA to Oakland CA.
Check engine light came on at that point with the following errors
Maf Sensor
ECT signal
Engine Coolant temp signal missing or faulty
I reset it and the check engine light hasn't come back on.

Sorry to be so in depths but I suppose it may help diagnose my current problem. My band and I have a 30 day U.S. tour booked for August and I need to make sure this baby is tip top before that. As of today I'm a little freaked out.

Starting this morning, my car shakes violently when I'm going from a complete stop to about 5 mph. When I'm stopped my engine idles totally fine. When I pick up speed it runs very smooth as well. It only starts shaking violently when I accelerate from a complete stop.
I checked my transmission fluid and the levels are fine but the fluid itself was a browish color which I understand IS NOT GOOD! From what I can tell a good start would be to change the transmission fluid and replace the filter. From what I've gathered, people are very divided on flushing the transmission some saying it could make matters worse.
Here are my questions.

1. It's looking pretty clear that I need to change the transmission fluid. Is there a specific kind of transmission fluid that I'd need and is there a tutorial anywhere on how to do it?
2. Is it possible that this could be related to something other than the transmission?

Thank you for reading and input would be greatly appreciated!
I feel this baby's pain whenever I give her a bit of gas from a stopped possition.

 

I would check the u-joints. When they freeze up you can get some violent shuddering on acceleration and/or braking. Drop the drive shaft and check each joint. Make sure there is no binding in any of them.

Before dropping the shaft, make sure you mark each section so it is properly aligned when you reassemble it

 

+1 on the driveshaft...
I seriously doubt that the transmission is causing the shake. Change of fluid is not a bad idea, no flushing needed, and filter change is not usually necessary.
https://www.brickboard.com/FAQ/700-9...X940FluidFlush

 

Thanks for the replies and hope! Unfortunately it is looking a bit more grim at this point. I just took it for a spin around the block and it's barely moving when I'm flooring the gas pedal I looked at the Transmission fluid again and besides being black it also appears to have a green undertone. Since the heater control valve is right about the dipstick, I think some coolant leaked in there when my hcv blew. It's looking pretty hopeless but I'm going to atleast attempt to swap out the trans fluid before taking it in. Does anyone know where the transmission pan is located on this vehicle?

 

under the transmission, of course... the transmission is immediately behind the engine.

but, draining the transmission pan only gets about 1/2 the ATF, the other half is in the torque converter and transmission cooler (which is inside the radiator), you need to follow the procedure on that brickboard link above to get all the ATF

anyways, a heater valve couldn't possibly contaminate the ATF with coolant. its more likely there's a leak inside the transmission cooler, whihc generally means a new radiator is in order.

coolant/water inside the transmission is bad juju, and not easy to flush out.

 

I recently had this happen also. Don't fret quite yet however, the Transmissions in these volvos are actually decently built. To start with. don't drive it for any extended period of time or at speed, sounds like you can't to that anyways. so that good. you may have to flush the transmission several times to get the water out... since oil is lighter than water there will always be a few drops in there without doing a rebuild... i would recommend changing it, then drive it for 50 miles, and flush it again when the tranny fluid is warm. All this happens after you replace the radiator of course... do this at least twice... you will end up wanting to flush your coolant system as well because now there is tons of transmission oil in it.. or do what i did and find clean manual tranny to swap in and get rid of your tranny cooler, in that case you just need a used tranny not a new radiator. haha

 

Hey guys!

So i followed the guide on the brickboard page to flush out all of the old fluid. Unfortunately, it' didn't do much. The car just fails to shift into drive but it seems to reverse just fine. When I shift it into reverse I get a loud thud and the car jerks a bit. When I shift into drive I just get a subtle click. No matter how hard I rev it nothing happens. I've let the car idle for a bit and the fluid is still red and smells fine to me. This makes me think the problem isn't a leak in the system.
Does anyone have any ideas of what I can do to attempt to remedy this problem instead of having the trans rebuilt?

 

assuming the shift lever on the transmission is going to the right place (the detents are inside the transmission), and the transmission throttle cable is properly adjusted and not binding, then you need a new gearbox.

Its likely much cheaper to find a junkyard tranny than to rebuild yours. if you find a recent wreck that appears to be a well maintained car, odds are pretty good the tranny is OK. a ratty beater car, less likely so. a junkyard car thats not wrecked, who knows why its there, could easily be a bad tranny.

you have a turbo, so its an AW71 transmission, used on any Volvo 740/760/940 turbo from 1990 forward. a 240 or non-turbo 740/940 AW70 transmission has the same gear ratios but isn't as heavy duty as the AW71. a AW7x from 1989 and older won't have the correct flexiplate or the notch for the Crank Position Sensor used on the LH 2.4 cars like your 1993. The notch COULD be cut, and the flexiplate swapped.