[dedwalker]

Hi all,
My 1981 244 GL manual Volvo story continues. Trying to eliminate shaking through the drivetrain is still a sag for me; I have now changed engine mounts, gearbox mount/s, and had the driveshaft support changed. Still having some shaking I can sense that there is still some coming from the driveshaft area and I have been told that the driveshaft universal joints (there is a rear at least, and maybe a forward one) may need repairing ......how does this hold up with peoples knowledge/experience? Also I'm now wondering about the repair I intend to do on the manual gearbox overdrive. I'm pretty sure I have the M46 gearbox; does anyone know whether I can put in an M47 gearbox? I would be a lot happier to eliminate the switches/ relays / solenoids and all that and have a plain 6 speed (5 forward) gearbox. Thanks for any help...Dave

 

[Tech]

I have seen the u-joints go bad before but it is not a common thing.Im not sure if you can swap out the M46 for the M47 I will try to do some research on it and see if I can find out any more.

 

[corny]

Dave
No question the universals need to be changed and no the gearboxes are not interchangeable. The mounts and ratios are different.
Corny

 

[dedwalker]

Many thanks Tech & Corny ..The joints don't 'look' bad (but that doesn't mean anything) and I can still feel vibration under positive compressive load with the clutch plates engaged (i.e. I mean the engine driving the wheels).....if I push in the clutch pedal..the vibration seems to go. ....guess this will mean having that universal joints (U joints) looked at.

 

[Tech]

They way you describe it does sound like a u-joint.Once you let off the gas and there is no torque driving it the vibration goes away.souonds like a bad joint.Do you hear a squeeking noise while accelerating?

 

[SKIP TUEL]

I tolerated a vibration in the driveline more than a year after similiar parts replacement. On a whim, I finally tried "re-phasing" the driveline, which is fancy talk for changing the position relationship of the front and rear shafts. Voila! The vibration is gone, and the car now accelerates silky smooth.

This is a pretty easy fix, and it only takes about an hour to do. After the car is raised up and on safety stands, take a piece of chalk and mark the front and rear shafts with a parallel line, near the center support. Then undo the four bolts that attach the rear shaft to the rear end. (Pull the hand brake to hold the shaft while you break the bolts loose, then release the brake to rotate the shaft for access to the other bolts.) When the four bolts are out, slide the shaft slightly forward to disengage from the rear end. Now move toward the center of the car, and slide the shaft toward the rear of the car, while "helping" the rubber boot off of the front shaft to prevent tearing it. Slide the shaft clear out until it disengages from the front shaft. (It is a good idea to now put a little light grease on the exposed splines that came out of the front shaft, and a little on the inside of the rubber boot will make it go back on easier.) Next, reinsert the rear shaft into the front shaft, but with the chalk alignment marks 90 degrees opposite of each other. Carefully reinstall the four rear flange bolts (cross-tighten), and road test. If this has some effect on the vibration, but doesn't make it go away, you may have to repeat the procedure, only setting the shaft at 30, 60, 180 degrees different. (On my car, I positioned the front and rear center u-joint knuckles exactly opposite each other.)

 

[dedwalker]

Many thanks for that Skip...will try it on next visit to mech...DW

 

[dedwalker]

Driveshaft shake problems are now vastly improved; since the universal joint replacement. I'll try Skips fix as well.

DW