It's hard to say what a mechanic would charge in your area to do the ujoint/center bearing job . I imagine the rate is for 1.5-2 hours labour ( anywhere from $35-70 per hour depending on where you are ) + parts. If they do need replacing don't forget the rubber support for the center bearing as well while you are in there.


If you take the shaft off yourself and bring it to a machine shop to have them press the bearings/ujoints it would probably run between $6 and 10 ea for the press work

www.fcpgroton.com has new ujoints for $8 ea center bearing kit which includes the rubber support for the bearing $14-15 ( you have to measure the driveshaft to order the correct ujoints )
But you can check it yourself, just get it safely up on ramps and stick it in gear with th eparking brake on and grab the driveshaft sections and see if there is any play in the ujoints.

Also if the overdrive is acting up it can buck and jump at strange times read : http://www.brickboard.com/FAQ/700-900/TransmissionManual.htm
for how to diagnose OD problems Don't forget to start by changing the oil in the transmission( atf type f ) first to elimanate that variable .

I need to ask, do you know when the timing belt was changed last on that engine? 50,000 miles max on the t-belt in these things . if the t-belt breaks, you'll have a 450 pound paper weight under the hood.
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-------Robert, '93 940t, '90 240 wagon, '84 240 diesel (she's sick) , '80 245 diesel