1950-1966 [Subscribe to Daily Digest] |
There's not much in those inner U-joints: just a cup (the big round piece you can see from the outside) that goes into the transaxle, and a T-shaped piece (which you can't see because it's inside the cup) that's attached to the driveshaft. The T-shaped piece has a small roller-bearing cap on each end, and fits into a slot inside the cup. When the cup turns, it presses against the roller bearings, causing the driveshaft to turn along with it.
That's it -- not much to go wrong! It's a very robust design that usually lasts a long time -- as long as the mechanic remembers to fill the joint with grease when rebuilding it, and as long as the rubber cover that keeps in the grease remains intact.
One common cause of vibration under power is that after very long mileage, the roller-bearing cap wears a slight groove in its matching slot in the cup. The groove causes the T-shaped piece to wiggle just enough to make a vibration you can feel. There's a simple fix: Take the cups out of the transaxle (they just pull straight out if you whack 'em hard enough) and swap them side for side. This swap makes them rotate in the opposite direction, so there's now an unworn face in the slot making contact with the roller-bearing cap.
Okay, the one thing that is NOT so simple about this fix is getting to the cups! The easiest way is to pull the whole drivetrain out of the engine, but that's a lot of work. If you're careful and patient, you can unbolt the lower ball joint on each side of the front suspension (don't mess with the upper ball joint; it's under heavy compression by the spring!) With the lower ball joint unbolted, you can pull out the hub assembly at the bottom and swing it outward just enough to pull the driveshaft out of the cup. (Make sure you've unclamped and pulled back the rubber boot on the cup before you start this.)
With the driveshaft out of the way, you can carefully pull the cup out of the transaxle. Then repeat the same process on the other side and swap the cups. MAKE SURE YOU DON'T KNOCK THE BEARING CAPS OFF THE T-PIECES WHILE YOU'RE DOING THIS -- if the rollers fall out of the cap, you're in for a miserable time trying to find them again. You may decide that pulling the drivetrain is actually easier, even though it takes longer to do -- but that's up to you.
Before you go to all that trouble, though, make sure you've ruled out other easier-to-fix stuff such as an unbalanced wheel, bent rim, flat-spotted tire, etc., etc. Unless you really LIKE pulling engines, that is!
posted by 68.227.170...
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
 |
 |
 |
 |
 |
