vibrating at 2000 rpms sitting still.

[Street fighter]

I took a break from the charger problem and rested my nerves. I got under the charger and checked front and rear u joints for the countless time., I noticed that the front yoke has a good amount of up and down play in it, just how much play should be in the shaft up and down? The yoke and bushing are new installed not long ago,I believe this up and down play my be my vibrating at 2000 rpms. I think the shacking sitting still may just be normal from the engine with the small cam it has in it.

 

[Curiousyellow71]

Should be tight with no movement. Usually there is barely enough room to get it together and put the c clips or internal snap rings in. That could easily cause a vibration. Maybe a yoke spread when it was being put together. Sometimes driving them apart or pressing them together they get sprung and you have to hit it with a hammer on the back side of the yoke to get it to go back to it's original shape. But, if that is what happened it typically puts pressure on the u joint and will cause it to be tight. If it's a new yoke maybe its defective..or the wrong joint, the cross isn't wide enough even though the caps fit.
If you think the shaking at a idle is from the cam...possibly the rubber is shot in one or both of your motor mounts?

 

[Fran Blacker]

The up and down movement is front yoke in trans or slop in u-joint. Wore out my tailshaft bushing because of a to short driveshaft. At 3200 rpm or above it would rattle. Tool to replace bushing is about $75.

 

[Ernie ingling]

Just an experement bring rpm up to get the vibe. Then one by one plug a pluge wire. Note vibe and rpm change across all cyl. Report findings

 

[Street fighter]

Should be tight with no movement. Usually there is barely enough room to get it together and put the c clips or internal snap rings in. That could easily cause a vibration. Maybe a yoke spread when it was being put together. Sometimes driving them apart or pressing them together they get sprung and you have to hit it with a hammer on the back side of the yoke to get it to go back to it's original shape. But, if that is what happened it typically puts pressure on the u joint and will cause it to be tight. If it's a new yoke maybe its defective..or the wrong joint, the cross isn't wide enough even though the caps fit.
If you think the shaking at a idle is from the cam...possibly the rubber is shot in one or both of your motor mounts?

 

[Street fighter]

The u-joints are good no play in them it's in the yoke. where it goes on the shaft of the trans I can raise it up and down I would say close to a quarter of a inch. I checked the end play of the yoke on some of my other cars and there is almost none. which make me think my problem is in the trans tail shaft bearing, I can be wrong. The trans is a tci trans that I have had for some time but less than 3000 miles on it, it works great, it will pend you back in the seat when she shifts.

 

[Curiousyellow71]

Who knows if tci actually puts in a new tailshaft bushing when you get a rebuilt tranny from them. Sounds like a good place to start. Unless the driveshaft is to short for some reason or splines have excessive wear, there are only a few options to allow that kind of movement.... A 1/4" sounds like a lot.

 

[Fran Blacker]

Looked on ebay for the tool. Not mine. Thttps://www.ebay.com/i/254104262633?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=254104262633&targetid=593772290333&device=c&mktype=pla&googleloc=9003318&poi=&campaignid=2086088136&mkgroupid=80059919711&rlsatarget=pla-593772290333&abcId=1141016&merchantid=6296724&gclid=EAIaIQobChMI_ojAu-rs5gIVip-zCh2OTQRCEAQYAiABEgIEg_D_BwEool and driver makes it easy.

 

[Ceedawg]

Who knows if tci actually puts in a new tailshaft bushing when you get a rebuilt tranny from them. Sounds like a good place to start. Unless the driveshaft is to short for some reason or splines have excessive wear, there are only a few options to allow that kind of movement.... A 1/4" sounds like a lot.

Replace bushing and rear bearing for that much play. Slip the tail shaft off and bushing and bearing are easy fix. Bushing has to go in right spot for oiling (very important). My friend the trans guy, did my 4-speed one (same as auto) in 10 minutes, new seal too

 

[NoCar2023]

Get the prop shaft inspected/balanced while you have it out.

 

[Fran Blacker]

It be nice to have a picture of tailshaft/yoke to see if D shaft is to short. With car on jackstands jack rear differential so it's ALMOST coming off jackstands. Then take a picture.
Nothing wrong with what Creedog said but me being a lazy f--k I bought the tool. Use hose clamp to make it easier to put tool in trans. Opened after in trans. That piece sticking out is pushed in fully before pulling bushing. There is a ring in ID to keep tool from collapsing when pulling bushing.

 

[Street fighter]

Who knows if tci actually puts in a new tailshaft bushing when you get a rebuilt tranny from them. Sounds like a good place to start. Unless the driveshaft is to short for some reason or splines have excessive wear, there are only a few options to allow that kind of movement.... A 1/4" sounds like a lot.

I might have gotten carried away about the 1/4 but there is 1/8 I am sure of. I replayed the bushing a while back but I had to pull the trans to get it out hard job. I had a new drive shaft made some years ago, because the guy at the shop told me that the shaft that I had in the car were known to cause the cars to vibrate I replaced the shaft, same problem.

 

[Curiousyellow71]

I might have gotten carried away about the 1/4 but there is 1/8 I am sure of. I replayed the bushing a while back but I had to pull the trans to get it out hard job. I had a new drive shaft made some years ago, because the guy at the shop told me that the shaft that I had in the car were known to cause the cars to vibrate I replaced the shaft, same problem.

Hmmm... not sure it's your problem. You could put some hose clamps on your driveshaft and go for some drives change clamp positions and see if anything changes...worse/better. Easy to try. Maybe put them on the tailshaft end see if the problem changes. If its vibrating there I think you could make it vibrate worse.

Have you checked your wheel bearings, you have new Tires but are the rims ok, harmonics can do weird stuff.

 

[Fran Blacker]

The driveshaft bushings are very tight only maybe .002 clearance. My worn out bushing had .010 to .012 clearance and rattled like crazy above 3200rpm.
As Creedog said bushing position is important for lubrication. Halfway out I marked the bottom so I could tell how new one should go. Note lube hole. New on left.

 

[Don Chapel]

deteriorating rubber can make a damper sound like the engines coming apart! It doesn't have to have spun. I've changed a couple on chev 6.5td's that people were scrapping the motor because of the noise, new damper fixed it!

That's what I was thinking or pinion angle