When cruisng down the highway there is sort of a solid yet mild rythmetic vibration coming through which is not from unbalanced tires. I have had this for almost 4 years now on 3 different sets of tires and different rims. I have heard the bushings need to be replaced in the steering column. Is this true and will it eliminate the column vibration?

It is not anything alarming or other type of vibration but its kind of bothersome that I am looking to get fixed. Only does this at 60+mph and does not really get any worse or violent if I am going 70 or 100mph.

Thanks

 

Suggest looking at a shaft imbalance or U Joints. bad trans mount and even driveshaft pinion angle.
I'd bet its pinion angle causing the vibe

 

Thanks for the help but I believe its something else.

In the last 3.5 years owning it I have had 2 different engines (468 BBC & 427 LSx), 3 different trans (6 speed, 200R4, 4L60E) all times having the same problem. I was told from a vette shop they thoght it was the bearing in the column not holding it firmly in place. Wanted a 2nd opinion before I yank out the column and replace these myself.

 

First off, sorry to hear of your recent problems with the car.
I know how difficult it is to find quality workmanship here, let alone somewhere else. Don't rely too heavily on vette shops.

I seriously doubt that the column bearings are the cause, they are most likely the result. Although as much as you have put into this car, I would do the complete column anyway, especially if it is a tilt. These acquire a lot of crud inside over the years and a good cleaning, polishing and greasing of the internals will make it better than when it was new.
You should be able to measure any shaft play just above the rag joint. If you are using a rack with universals, that can transmit vibrations a lot easier, but again the column shouldn't be the cause. In fact even a loose, worn steering gear won't cause a vibration if the running gear is true.

It's tough chasing a small vibration., but I would check tires, hubs for runout, tires for runout, tranny misalignment, joints etc.

I would start with tires (easiest and cheapest), even though you have tried several sets. Most places around here that balance have no clue with problem tires. The only machine that works well with problem tires is a Hunter GSP9700.
Call OK Tire in South Lauderdale (954) 523-3198 (near Lesters Diner) or whoever else is fluent with that machine.
Also contact Florida Region SCCA that race a lot in Homestead about tire cutting, shaving and truing. The racers should have hands on with tire problems. You can take the best balanced tires in the world, shave them and get a smoother ride. Don't rule tires out, I could go on about tire problems, but I don't want to type a book.
Check the tires just as you would a rotor for runout.

Checking for shaft alignment is a bit trickier, but you can shim the rear tranny mount a bit and see if it gets worse or better. There used to be a driveshaft place just off Broward and if anyone can find a driveline vibration, they could. Had them balance some drive shafts for me years ago.

Let us know how you make out.

 

I have same issue and an open thread. Mine I'm thinking has to be the tires. About to get new ones and will know then.

 

I've had the same issue for years. Changed tires, rebuilt the front end, new steering box, and yet the viberation is still there. I have a new steering column to put in, just haven't got around to installing it. Best of luck. Keep us posted if you get it worked out.

 

Rob, give me a call.
Mike

 

Sounds to me like you have to find the one constant that makes it happen. To do that you have to start eliminating what you can.

You say it happens only at 60 and above.
Does the frequency stay the same or does it speed up as you go faster?

If your doing 70 and you put the trans in neutral does it still happen with the engine idling at 70? This would eliminate the engine and accessories but not the rear end or parts of the transmission and driveshaft. I have seen unbalanced or bad tires/rims cause this above 60 and pulled belts in tires usually show up at 30 and below.

Could your speedometer gauge have the speed-minder thing running and is set at 60 or maybe the gauge is simply got a bad spot at those higher speeds? Disconnect the speedometer from the trans.

Maybe you have a bad body mount at #1 or #2 and body is hanging on the steering column and bouncing on the shaft at those speeds but I cant see that being rhythmic?

 

Thanks guys for the tips...

I also forgot to mention I have had also 3 sets of tires and two different sets of rims. This problem has always been there. It is nothing too alarming but it is something that obviously is not right.

Sorry for starting another thread. I looked but must have missed it.

Noonie...I had Kaos at Ok Tires (Scott & Mark) 2 weeks ago. That shop is EXCELLENT and the car is perfectly straight down the road and handles awesome now. Nothing like an old school alignment with chaulked tires and mirrors I guess. Yes they did the balance also.

The vibration does not really get any worse or violent with increased speed.

Have not tried throwing it into nuetral yet while cruising.

I will try to make a video of it.

Speedo is fine. It is confirmed with GPS also the speeds I am running.

 

Kaos,
Are your wheels hub centric? If they are not and they are lug centric, you can get a piece of metal machined to fit in the area of the lug centric wheel that will fit snugly over the hub. Love your car.
Good luck.

 

Just thought of something else...Do you have power steering?

Can you temporarily pull the power steering belt(s) off and take it up to 60 or more?

 

Both sets of wheels where hubcentric

I can't pull of the PS belt. I have a LS motor setup

I really appreciate the suggestions. It is just an annoying vibration that on my 700 mile round trip to Orlando & back got old feeling the vibes.

It is a tilt & telescoping column.

I think I am going to pick up the assembly manual this weekend and go through it entirely and then do basically a complete rebuild taking it all apart replacing anyting that could cause it and then cross fingers and hope for the best.

I will be sure to report back once I get it back in. I spoke with Mike (tracdogg2) and there appears to be a LOT of possible parts within the column that could cause this.

 

The AIM will not help you with disassembly of the steering column. It will help with removal of the steering wheel, telescope lock, and horn parts. I might suggest my disassembly & repair papers on the T&T column. Paper #1 does outline several tests that you can perform with the steering column still in the car. It might direct you to some areas of looseness that might need to be fixed. (Whether or not it might direct you to the source of your problem, I can't say.)

You can also refer to the Chevrolet Chassis Service Manual for your Vette.

Here are the locations for papers #1, #2, and #3:
http://jimshea.corvettefaq.com/?p=1004

Here are the locations for disassembly line drawings #1, #2, & #3:
http://jimshea.corvettefaq.com/?p=1009

Here is a scan of the blowup of the steering wheel and horn parts from the AIM
http://jimshea.corvettefaq.com/?p=985

Here is a blowup of a 1969-76 T&T Steering Column. It might help with identifying parts by name.
http://jimshea.corvettefaq.com/?p=997

Jim

 

Hell Yeah!!! This rocks. Thanks

 

I had that vibration from who knows where for years, it got worse when accelerating. I noticed on the steering wheel when vibrate. My mechanic is a corvette specialist, and he can’t find the source of the eventual vibration; I went to another specialist and the same luck. Recommendations like tires out of balance, old steering box failed, suspension bushing, and shafts u joints
I replaced tires and rims sent to re-finish and balance to perfection by alloy wheel specialist, installed Steeroids system and replaced front bushings, repair transmission, and main shaft, replaced both half shaft, replaced rear suspension including new trailing arms assembly from ecklerscorvette, and the list goes on and on… the problem persisted.
A few days ago I was replacing the power steering belt, pending from when installed the Steeroids system and realized the harmonic balance was like hitting the timing belt cover, the harmonic balance was separated form the cast and was moving around, not making any noise at all.
After replace the harmonic balance with timing belt set and cover vibration disappears completely, that eventual vibration made me crazy and was impossible to detect because not always happened.
The simplest solution it’s not easy to find

 

What's the condition of your rag joint? I had this same issue a few years ago, replaced mine and the issue cleared up.

 

it was a bit of a big puzzle replacing a LOT of parts in the steering column but I got it done over 2 weekends and overnighting various parts. Its 99% better. Not perfect but it is night & day different. Very solid & secure feeling. Hard to believe several little parts here & there can create such a vibration mess.

Thanks for the tips....much appreciated.

Now I am looking into replacing the grand am steering rack. Its been on the car for over 30K miles and I have more than acceptable steering wheel play left to right that is becoming annoying and all the universal joints are set correctly with looks of things from underneath the play is coming from within the rack itself.

I have severe bump steer (always have had it) which I have on my TDL (to do list).

 

Vibration passed to the steering wheel, rag joint was perfect but substituted with U-joint and shaft from Steeroids system that replaces all parts (every thing included) and fits with no modification and a weekend project (for some a few hours).
The ride its not like S series Mercedes but super smooth, no vibration at all. The change was night and day.