Need help looking for driveshaft bolts..please

[ShaneHayes]

Okay so I have the car up on jacks right now in the garage, and I am trying to fix the "thump" when I press the gas and let off. I was told by a few people to check the driveshaft bolts to make sure they are tight. Where are they? I can't find shi#. I tightened up those two bolts that hold that big rubber bumper deal under the yoke, but I don't think that does anything. Also, when in gear, the drive shaft has a lot of play in it. Does that mean I have to replace my diff. bushings? I'm just trying to illeviate from taking it in the shop and getting raped on labor, etc.

 

[ShelbyGuy]

the four bolts holding the driveshaft to the pinion flange are what they mean

being able to turn the driveshaft quite a bit has to do with the amount of backlash between the ring gear and the pinion gear in the differential. thats your 'play in the driveshaft'

your thunk when getting on and off the gas is either the aformentioned backlash issue, or the bushings that support the front of the differential housing.

hope this helps

 

[ShaneHayes]

thanks a lot. i did see those 4 bolts holding the driveshaft. do i need try and tighten the back part, and the front? how do you solve the backlash? will diff bushings help some? where are the diff bushings? sorry for my ignorance, and thank you very much for your help.

-shane

 

[ShelbyGuy]

the backlash between the ring and pinion gears is set by how thick the shims are inside the differential housing itself. not something a person can do without a shim assortment, some gear marking compound, and a dial indicator. moving the ring gear closer to the pinion gear decreases backlash.

the front of the driveshaft is a slip yoke that just fits in the end of the transmission. as long as your u-joints arent worn out (unlikely, but possible) there's nothing to do on that end.

the diff bushings are at the front of the housing, and on the driver's side of the rear cover. where the differential housing mounts to the car in front, you'll find rubber bushings above and below the mounting ears. sometimes they melt away or otherwise loose their rubber-ness. the one in the back is harder to see since its inside a big metal bracket that bolts to the rear cover.

 

[ShaneHayes]

Problem Solved

I tightened those two bolts that are mounted to that big rubber piece that sits under the diff. Well I noticed that huge rubber (bump stop?) was wiggly, and felt loose. I tightened those two bolts down like a mutha, and now the car feels sooo much more solid. I don't get that abnoxious "thump" when I hit the gas, and let off. Before it felt like something was going to come through the floor board. Thanks Shelbyguy...I may try and eventually change out my diff. bushings anyways.
One thing...I have this annoying creaking sound coming from the rear passenger side. You can hear it when you driver over a bump. I tried to WD-40 all the bushings on that side, but I'm starting to thing the strut is going bad? Car doesn't pull, or vibrate, etc...Just hear that creaking noise. Any suggestions?

 

[ShelbyGuy]

you would need a shock tool to do it right (vice grips just leave teeth marks, and if you round the top off the shock you're fubar) but often times the bushings wear on the upper shock mount.