sqzbox

Well, here it is. I've had a vibration for (about 7k mi.) 2 yrs.
I've checked all the rims (straight) had the tires checked and re-balanced. Had to replace two of them for out-of-round. Checked axles (straight). The vibration has steadily got worse over time so I decided to pull the driveshaft. The u-joints are good, pinoin is good and the driveshaft had a little wobble when I put screw driver upside it (about an 8th of an in. or less.) while the car was running. I checked the shaft with a straight edge and it's straight, and all the weight's are still in place.
Sooo, I looked at the splined output shaft comming out of the housing and it's wobbling pretty good. I can move it 1/2 an inch either way (up and down and back and forth).
I can't see this as being very good for driveshaft balance so I figure something is not right inside the housing.
I have broken a tailshaft housing before on a 727 chry. trans. because the bearing went bad at 130 mph and Aamco put a used one back on cheap and all was good.
My question is how much trouble is the tailshaft and housing to replace on the 700R-4? and are any special tools required to replace them?
There is an 85 camaro with a 700R-4 in it at the salvage yard and is easy to get at right now. any help would be appriciated!

91Z28TTOP

I don't believe the output shaft should have that much play in it. You could pull the tail shaft off and see what the bushing looks like. If you have been driving around for 2 years with it in that condition, I would think the tranny is on its way out the door. If you go to the bone yard check the out put shaft on the 700R4 in the yard and see if it has that much play. I have mine apart and half way back together on my work bench and the tail shaft has next to no wobble in it.

thirdgen88

Sounds like the extension housing bushing (the bushing the driveshaft goes into) is just worn... You can replace it fairly easily..

sqzbox

New developments! I checked the teeth in the yoke and where the output shaft ends in the yoke, it has started to twist the teeth
3 in. deep in the yoke. I believe, this shows that the yoke is not straight on the output shaft which could only be caused by a bad tailshaft bushing. Mind you now, it's been two years and only 7,000 mi. and has gone from a slight vibration to a door rattler in the last 3 mo. since I started driving it 82 mi. a day to work at 75 MPH.
I went to the salvage yard today to pull the driveshaft out of the 85 camaro and found it laying under it! Someone had already done the work for me! The yoke teeth look new. 10 bucks and it was mine. The mechanic I talked to about the tailshaft is going to LOAN me his tool that I can pull and re-install the bushing without having to yank the tail housing. I figure I'm getting off easy as far as money goes, new u-joint, bushing, and seal plus 10 bucks for the shaft and yoke is hard to beat! after I've already spent money for 2 new prorated tires to replace the 2 that were out of round, re-balance twice, replaced a worn out steering box, alingment, and countless hours checking axels, rims, tires, and everything else I could think of! Man that WS-6 suspension is hard to diagnos because it rides so stiff.
Plans are to do the work this sat. I'll update soon as I test drive it.

sqzbox

sqzbox

That's not it! I pulled the drive shaft, the rear seal (that was starting to leak) and the tail shaft bushing. I replaced the bushing and seal and put the drive shaft I got from the 85 camaro in. I measured the bushing with a micrometer and got .063 on one side and .052 on the other 180*. The dimples on one side were visibly smaller than the other but only .009 didn't seem execive enough to cause what I was feeling at 70-80 MPH.
I'm going to drop the flywheel cover and check the mount bolts and balance weights on the converter and flywheel tomorrow. I figure if one of the weights have come off, it will be laying in the bottom of the cover. You wouldn't believe how bad the vibration is at hwy. speeds and not be obvious what is wrong. When I flic my bic to light a smoke at 75 MPH even the flame is bouncing up and down!
The tires are running round, rims are straight, brake drums are straight, and can't find anything out of round.

Duck

First thing I'd do is exchange the iron driveshaft for a aluminum version, only about $100 used, might be an easy fix to the problem. If you can't chase the bad vibe down, find a auto service agency that has a MTS 4100 NVH Analyzer, manufactured by Vetronix Corp of Santa Barbara, CA [www.vetronix.com]. it is well-known by techs to isolate and identify noise, vibration and harshness. Basically, techs put the car on lift, attach sensors, run the car and then analyze the data. It can also be used in real-time on the road.

Duck

ttt

Duck

More info on vibe analysis...

sqzbox

Thanks Duck! Good reading on the vectronics. Thats pretty close to my problem except, my vibration speed is a slight wobble at 45mph to 50mph and smooth to 60 with a continuious vibration from there on up and get's worse the faster I go. I think I've eliminated the drive shft and yoke as the problem though after replacing the shaft and yoke. The rpm range I'm having the most vibration at is 1700 to 2300 at 80 mph with 2:73:1 rear ratio. 80mph is as fast as I dare to drive it for fear that whatever it is will blow up!
I've replaced the steering box and the center link on the front end and had it alinged but the mech said I still need outer tie rods and showed me play on the front end. I'm going to replace them next week end and take it back for re-alingment.
One might think that tie rod's wouldn't cause a shake that bad but the front end is pretty sensitive to anything out of wack because of that super stiff WS-6 suspension. More updates to come!~

iggy1991

I have the same problem with my cammy. Its at a tranny shop right now looking at the output shaft wobble as discribed above by SQZBOX. They said that that is normal and if the bearing was bad the tranny would leak alot of fluid out of the tailshaft. They think it is engine related and I'll be going there first thing in the morning to look at it myself and tell them what I think after reading a few other posts on this site.

sqzbox

Hey iggy, about your TBI chip, I've been looking at one for my 88 form. and was wondering about the performance after the change. My 88 is a stand alone chip and the one off the shelf he offers claims a different fuel curve and the speed limiter removed.
Do you think it would be worth the swap? I've only got minor mods from stock such as 3" cat back and drop base open element.
sqzbox

Free Bird

iTrader: (1)

Did you check to see if you still had the balancing weight on the stock DS? If it comes off, it'll vibrate.

Maverick_IX

Where are those located, my car has always had a vibration from 75-80 mph.

iggy1991

Sometimes what you think is a drivetrain vibration is really something in the tire/suspension system. If you get a vibration at a certain MPH and doesn't really go away when you put it in neutral than most likely it has to do with tires (flat spots, unbalanced), bent rims/axles, worn steering components, pinion angle.
If you only get this vibrtation at certain RPMs no matter what the speed is than it is drivetrain related, balancer is bad, flywheel unbalanced, torque converter, transmission, driveshaft, or rear end related.

I've delt with both and so far haven't been able to fix the current vibration which is why I have a tranny shop looking at it again in the morning. My other problem was at about 70 mph the car would vibrate and get worse at speed increased and it didn't matter what gear I was in or if it was in neutral. Finally went away after replacing the goodyear eagle HP tires I had on the front. Didn't have much luck with them. I replaced a few other things but didn't clear up like getting new tires did.

Maverick_IX

Sorry to be a hi-jacker:

This car is on its second set of rims, and high performance Nitto's. The vibration only occurs from about 75-80 (no where else). I wonder if its not just the speed at which the frequency of the vibration begins to resonate.

iggy1991

The tranny shop looked at the camaro and found nothing obviously wrong. I already knew that part. He did disconnect the torque converter lockup plug and the vibration was 90% cured. He said he didn't really know why that was and has to do some reasearch on the topic to figure out how to fix this. He's gonna get back to me on monday and tell me what he has come up with. Hopefully someone will have some insight to to this problem.

sqzbox

Well here it is. I got the new outer tie rods in, took it to a shop I trust and all is good with the front end now. All he had to do was set the toe, caster and camber was right on. I can cruise down the road and let go of the wheel and it stays straight.
I talked to the mech. while he was dialing in the front end about the vibration I was chasing and he checked the front tires and noticed that the left front wasn't smooth. We spun the tire around and it had a pretty good up and down movment. I'm like WOW! I don't even have a thousand miles on these two front tires and one is out of round?
As soon as I got the car done, off to sears I went to bitch about it and they pulled the fronts off to check them and found the tire is ok but the rim is bent. How strange, the car was smooth with the worn out bridgstones I replaced and now the whole car is shaking like a ***** with a vibrator in the back seat!!!
I said ok, let's check the rears too. Now one of the rears is bent also! Get this, both rims are smooth and round on the outside bead and bent on the inside bead I claimed they bent the rear with the first set they put on and then the front when they replaced the two out of rounds. Guess what? all of a sudden, they claim there not responsible for bending alloy rims and won't replace them (with what? a new set of after markets) I want to keep the factory rims and keep the car as close to stock as I can. And then they show me the disclaimer on the back of the work order (after the fact) so now I'm screwed! I've got nice new tires and my car is riding like a go cart with square wheels.
Thanks SEARS for nothing. My recomedations to all out there in F-BODY land is DON'T take your car to SEARS! Find a reputable tire shop that will BACK their work. Get this, they even tried to blame my stiff performance suspension for being so sensitive to slight imperfections and road condition for feeling so much vibration The bridgstones I had on it before were worn smooth in the middle on the rear and both edges on the front and still rode smooth as glass!

Anybody want to donate a set of straight formy rims to me?

iggy1991

That really sucks!

Spazz698

As a tech I can say there's little chance sears screwed up your rims, unless the person working on it managed to drop your car off the lift, which is possible but rare. Usually a bent inner rim is from potholes, or curbs but f-bodies are so low that one's really unlikely. Now here's the thing: sears shouldnt have touched your tires til you were informed they were bent. It's company policy to report any damages they find thats not normally visible like that (unfortunately, I used to work there as well, I hated that place) Bent rims on a balancer make it really easy to spot so I wouldnt know why they didnt see it.

Til you get new rims, put the bent ones on the rear, wont do much for vibrations but it wont screw with your steering. Oh btw, I might have a pair of rims, which ones do you need?

Duck

This happens often on Oahu, HI, since the roads are cratered so bad from pounding rain and neglect by the city of Honolulu. We just have the damage fixed, take a photo of the pothole and send the bill and evidence for payment. Honolulu pays a lot of them... So find that big pothole and send in the bill, your city is responsible for maintaining the roads.

Confuzed1

iTrader: (4)

Huh? I think Sears or anyone else is fully capable of screwing up rims. I thought he said he had tires put on at Sears? Pretty easy to bend the lip of a rim on a tire machine if you have no clue what you're doing. But I do agree when you say it probably wasn't caused by dropping the car off the rack.

I've ran into inexperienced guys who try to balance tires, and as soon as they see it needs ALOT of weight - they say your wheels are bent. After all, No way a molded tire can be out of balance right? - WRONG! It's COMMON!!...

Someone with a bit more experience just might try breaking the beads back down, rotate the tire 180 degrees on the rim, fill it back up and re-balance. At least 80 percent of the time - it will then require 1/2 the weight as it did before, most times way less than that!

I picked up a set of tires at Wally-mart for my Cavalier a while back, and I couldn't believe the kid that installed (and supposedly balanced the tires) stood in front of me with a straight face and said 3 of 4 rims were bent on my car!! OH BTW - that was AFTER they installed the tires. I called the manager, and a training session commenced. What do ya know? All the rims were OK after all!

I put in a few years at a tire center back in the day, so I know all the pitfalls. And I've also bent an aluminum rim on a tire machine myself!!

sqzbox

When I got the 4 new tires, I could feel a problem right off the bat! even at 45 mph. It felt like they were out of balance and I put up with it for about two weeks untill I had time to return 35mi. to sears and get them re-balanced. There was a little improvement but not much. When I returned again, they did turn the tire in question 180* and still no improvement. They replaced the two front tires for out of round and the left front still took 6oz. of weight to balance and it rode worse that it did before.
I am the only driver of this car and I know I haven't hit any potholes. As far as putting the rim in question on the rear, no go!
formula rims won't mount rear to front because of the difference in off-set. And another thing, A coats tire changer WILL bend alloy rims on the inside bead from the arm underneath.
I now have one bent rear rim and one front rim that were smooth and round when I drove in. How do I know that?
When I bought the car from my daughter-in law, I had a vibration problem and checked all the rims and axels and had to get all the tires balanced and replace the right side axel because it was bent. Everything was smooth with worn out bridgestones!