73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: 77 cc lb on July 20, 2010, 06:05:13 pm

Title: driveline vibration
Post by: 77 cc lb on July 20, 2010, 06:05:13 pm: i went for a ride today and the driveline started vibrating bad. i've done my research here and found it could be the u-joints. my question is does it matter what style u-joints you use (the c-ring or snapring style)? because i switched styles when i changed them. thanks for any advice.
Title: Re: driveline vibration
Post by: Lt.Del on July 20, 2010, 06:13:08 pm: how long ago did you change the style? has it been vibrating since? If not, I dont think that's the issue.

Your driveshaft is balanced. Could be knocked off balance.

wheels balanced correctly?

Wheel cracked?

I'd jack up the back and manually rotate the driveshaft and see if anything is out of whack.
Title: Re: driveline vibration
Post by: 77 cc lb on July 20, 2010, 06:22:48 pm: i just changed them a month ago when i disconnected the driveshaft to change my flywheel. today was my first ride since changing them. everything was fine before so would they make a diff. or is it in driveshaft possibly?
Title: Re: driveline vibration
Post by: Lt.Del on July 20, 2010, 06:58:36 pm: did you mark the driveshaft prior to removing it? It should go in the same way. If the shaft was put in 180 degrees off, it may vibrate.

I'd still jack it up, put the shaft 180 degrees around (if you didn't mark it prior to removal), reattach and really look at the joints and spin the whole shaft and rear axle just to see if the joints are secure.
Title: Re: driveline vibration
Post by: Irish_Alley on July 20, 2010, 07:11:05 pm: Weights off the wheels can do it too
Title: Re: driveline vibration
Post by: Blazin on July 20, 2010, 10:16:45 pm: Never knew you could use internal snaps clips on shaft that was supposed to take externals, or visa versa?
I would take the u joints out and put the same back in that came out. You didn't mention which you went from / or to? Sounds like the joint slipped to one side or the other?
Title: Re: driveline vibration
Post by: Irish_Alley on July 20, 2010, 11:43:22 pm: i can see if you went from a snap ring to a c ring but not the other way since the grove aint there to use. also make sure they are seated right in the yoke and not sitting on a tit
Title: Re: driveline vibration
Post by: 77 cc lb on July 21, 2010, 09:59:53 am: i know i made the mistake of not marking the driveshaft so i will try rotating it 180 sgt del. i looked at it yesterday and the center shaft holder on a double driveshaft was off center a little would that make a diff? i went from snapring to c-ring u-joints irish.
Title: Re: driveline vibration
Post by: Grim 82 on July 21, 2010, 10:28:34 am: I'm not sure exactly what you mean but if anything is off center it will vibrate. If you didn't switch anything else out you should be using the same u-joint that you took out.
Title: Re: driveline vibration
Post by: greatdane on July 21, 2010, 10:30:05 am: You say you changed your flexplate! Is there anyway your converter bolts have come loose? I have herd that causes a nice vibration.
Title: Re: driveline vibration
Post by: 77 cc lb on July 22, 2010, 01:45:06 pm: the chilton manual says the 77's w/ double shafts has an align. key so i don't think i can have the shaft 180 off. i am going to switch out the middle u-joint back to the snapring and see what that does.
Title: Re: driveline vibration
Post by: Irish_Alley on July 22, 2010, 06:44:04 pm: If you take it out of gear going down the road does it still vibrate?
Title: Re: driveline vibration
Post by: Blazin on July 25, 2010, 11:00:24 am: If the carrier bearing is off center or in cocked to the shaft it will cause issues.If the rubber in it is bad it will cause a vibration.