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Tech Area => General Buick Tech => Topic started by: rhturbo on July 21 2018, 09:43:10 AM

Title: issue with vibration at 60 mph
Post by: rhturbo on July 21 2018, 09:43:10 AM
Hi everyone,
Just discovered this site yesterday. Some great info here. I am new to the Turbo world and just bought a 1987 GN last week. I am having a couple of issues one of them being when I reach speeds of 100kmh (60mph)  I get a bad vibration in the steering wheel and front end seems to be shaking. If I push it past 120kmh (70mph)  it gets better and seems to almost disappear but is still somewhat there. If I go below 80kmh all is good.


I don't believe the rotors are warped because when I apply the brakes its very smooth with no vibration plus that would only show up when braking

The car had a safety inspection before I bought it last week and it passed which means they supposedly checked the front end.  I took it into a different garage to have it looked at. They examined front end and couldn't find anything wrong.  They suggested the wheels needed balancing. Seemed reasonable so I had them do it but problem is still there. They then suggested that I replace the two front tires as possibly one of them had a flat spot or other issue. I replaced both front tires and still same problem.  So $500 later I am no further ahead


I am taking it to a different shop next week that specializes in both  classic cars and high end cars and hoping they can help. Can you think of what might be causing this ? I was thinking maybe a damaged rim (there is nothing visibly wrong) but if that was the case wouldn't that show up when balancing ?
Title: Re: issue with vibration at 60 mph
Post by: Scoobum on July 21 2018, 10:35:37 AM
If you have access to 2 other tires and rims...throw them on and give it a whirl. If it straightens itself out...then you know you've got a tire or rim that's fubard. If it remains...then it's a front end issue. Sure the  front shocks are okay?
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 21 2018, 11:54:51 AM
Thanks for your reply. I have been watching your video. excellent info. Cant say for sure if front shocks are o.k but am assuming that both garages it went to would have checked that ? My back tires are a different size so I don't think I can move them to the front. Hoping the shop i take it to Wednesday can figure this out.
Title: Re: issue with vibration at 60 mph
Post by: nocooler on July 21 2018, 12:35:01 PM
If you want it fixed do it yourself or take it to a place that you can trust.

Are you sure it’s not a driveline vibration?

How long has the car sat? Are the brakes stock? Suspension? Stock wheels? Radials tires on all four corners? How’s the alignment?
Title: Re: issue with vibration at 60 mph
Post by: Steve Wood on July 21 2018, 01:02:38 PM
If the car has been parked for a few years, check the tires.  they do take a set after awhile and run like they are square at speed.  A good balancer should show them to be out of round.

Also, check the u-joints
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 21 2018, 01:38:03 PM
Thanks everyone, Tires on Front are brand new. Just replaced them to try and solve the issue. I thought about the possibility that  the drive shaft was causing the issue but when the problem starts I put it into neutral and coasted and the vibration did not go away until i gt below 60 mph. Stock rims all around . Brakes are stock all around. brake pads were changed last week on front rotors. Hoping the shop can measure run out on rims to see if that's an issue.
Title: Re: issue with vibration at 60 mph
Post by: TexasT on July 21 2018, 07:49:28 PM
Did you get under there and tug that drive shaft around? The ujoints could be original. They spin with the axle as the car is moving. I would swap the front n rear tires and see if the vibration moves. If the backs are wide dont do any real sharp turning while conducting this test, and really a different known good set of tire on the rear would be better.


Did you let us in on your location? Might be some one local who could help with some part swapping to see if you can track down the prob.


I just looked. Bunch of guys in the GTA, what part are you in?
Title: Re: issue with vibration at 60 mph
Post by: Scoobum on July 21 2018, 08:38:32 PM
GTA. Where's that?
Title: Re: issue with vibration at 60 mph
Post by: TexasT on July 21 2018, 10:00:19 PM
Yes Brad, where is that? Haha
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 22 2018, 05:20:09 PM
I haven't checked the drive shaft. I will check it tonight
Title: Re: issue with vibration at 60 mph
Post by: 1KWIKSIX on July 22 2018, 05:54:15 PM
I had a similar problem with vibration some years ago, spent a lot of time chasing my tail.


My transmission shop found my transmission Tail Shaft bushing was sloppy, allowing too much up / down movement of the front yoke, so he replaced it.

Finally took the drive shaft to a drive shaft specialty shop and here's what they found:
1) drive shaft had a slight bend / bow to it....they straightened it out in a hydraulic press
2) front u joint was not centered in the yoke
3) they replaced both U joints with Spicer (no grease fitting)
4) re painted the drive shaft black





Problem cured.......No more vibrations!
Title: Re: issue with vibration at 60 mph
Post by: daveismissing on July 22 2018, 09:38:46 PM
In the old days we might have pulled the shaft out and had our buddy tow us a bit as a test
Title: Re: issue with vibration at 60 mph
Post by: nocooler on July 22 2018, 10:29:38 PM
I'd check the u-joints and then re-index the shaft 180*, sometimes that's all they need.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 23 2018, 04:53:59 PM
Starting to think that it might possibly be the driveshaft as some have mentioned. So far everything else seems to check o.k
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 25 2018, 11:13:41 AM
Gave up on trying to figure this out myself. I dropped the car off at the shop this morning. I will let everyone know the outcome when I hear back.
Title: Re: issue with vibration at 60 mph
Post by: earlbrown on July 25 2018, 02:14:34 PM
Why do I feel another ''shop charged me $XXX and fucked my car up even worse'' posts on the way?
Title: Re: issue with vibration at 60 mph
Post by: TexasT on July 25 2018, 07:47:58 PM
Pretty much. You should have pulled the shaft and taken it to a driveshaft specialist. I hope you turned the boost down or disconnected the wastegate rod. Be sure to check the fender wells and quarter panels for rubber when you pick it up.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 26 2018, 05:22:34 PM
Car is back with same issue. Will have take it back again tomorrow. Drive shaft was removed and checked, u joints were checked, shocks checked, wheels re balanced (again) Given this is my first GN and I have nothing to compare it to how tight are these cars ? Can I expect no steering wheel shake at 50- 60mph ?  Below those speeds its fine. 
Title: Re: issue with vibration at 60 mph
Post by: Scoobum on July 26 2018, 05:33:00 PM
I can fall asleep at the wheel with my GN on the 401 it runs out so smooth.
Title: Re: issue with vibration at 60 mph
Post by: earlbrown on July 26 2018, 06:08:59 PM
Car is back with same issue. Will have take it back again tomorrow. Drive shaft was removed and checked, u joints were checked, shocks checked, wheels re balanced (again) Given this is my first GN and I have nothing to compare it to how tight are these cars ? Can I expect no steering wheel shake at 50- 60mph ?  Below those speeds its fine.

It's a grandma car, you shouldn't feel anything.   Lets get back to basics.

First, jack one wheel off the ground where it's BARELY not touching. Then spin the tire. You're looking for a bent rim or a tire that isn't round.    If those are out, I don't care how much you spend or how many 'experts' lay hands on them.
Title: Re: issue with vibration at 60 mph
Post by: Steve Wood on July 26 2018, 07:03:15 PM
If it was my car, I would do some of all the above.

I would jack the wheels off the ground and grab each one and see if I could wobble it by grabbing on each side and attempting to wobble it.  In this case, I would be trying to eliminate a bad wheel bearing.  Spinning it should show no run out.    You can check for run out with a dial indicator if you have one.  If it's not visible, when you spin it, it should be good.

Then, with the rear wheels off the ground and the front wheels chocked, just in case, I would start the car, put it in Drive and ease down on the gas gradually until the speedometer is above the normal point of vibration.  If you have vibration, then you know it is in the drive line somewhere.  Get someone to look at the driveshaft while it is vibrating or shaking and see if you have any wobble in the driveshaft.  I would like to think they checked it for wobble in this manner and followed up with a balance check as well as a straightness check.  Many shafts will have a balance weight added to them.

If you found no problem with the rear tires, go back to the fronts.  Assuming you checked the wheel bearings for correct adjustment and they spin properly with little or no run out, I would then check the control arm bushings to make sure one has not disintegrated.  The passenger side rear upper control arm bushing is notorious for being destroyed by heat from the down pipe.  Usually, it is evident by simply looking at it but you can pry on it and make sure the arm cannot move around on it.

If I had not found it yet, A good roadforce balancer will show if the tires are in the normal range of balance and the wheels are true.

You can also check the shocks are tight and the mounting bushings are good.  A google will show you how to check for bad ball joints, tie rods, etc.

Being methodical always helps
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 26 2018, 07:03:45 PM
Car is back with same issue. Will have take it back again tomorrow. Drive shaft was removed and checked, u joints were checked, shocks checked, wheels re balanced (again) Given this is my first GN and I have nothing to compare it to how tight are these cars ? Can I expect no steering wheel shake at 50- 60mph ?  Below those speeds its fine.

It's a grandma car, you shouldn't feel anything.   Lets get back to basics.

First, jack one wheel off the ground where it's BARELY not touching. Then spin the tire. You're looking for a bent rim or a tire that isn't round.    If those are out, I don't care how much you spend or how many 'experts' lay hands on them.


Good to know. At least now I know that this isn't normal.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 27 2018, 08:39:36 AM
Thanks everyone for all the great advice.This is so frustrating. The steering wheel and front end vibration is bad enough that you would think the problem causing it would be very obvious but apparently not. Certainly a methodical approach to diagnosing this makes the most sense. Its just going to take some time.
Title: Re: issue with vibration at 60 mph
Post by: Top Speed on July 27 2018, 10:56:04 AM
Could be your a tie rod or the bushing on the upper control arm near the down pipe that fails due to heat.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 27 2018, 12:25:54 PM
I took it back this morning and they are stumped and have given up so I guess I am on my own. They are convinced there is nothing wrong with any of the suspension parts, control arms, ball joints tie rods etc... The only thing left to try is a different drive shaft and two different front tires. I will have to see what I can dig up.
Title: Re: issue with vibration at 60 mph
Post by: Steve Wood on July 27 2018, 02:14:41 PM
you can elevate the rear tires and prove the driveshaft good/bad as I suggested.

A quality shop with a roadforce balancer can prove the tires and wheels
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on July 27 2018, 02:53:08 PM
So assuming everything that's been checked multiple times so far is not the problem (Ball joints, Control arms, tie rods, wheel bearings, shocks, springs) I am down to drive shaft or tires ?
Title: Re: issue with vibration at 60 mph
Post by: Steve Wood on July 27 2018, 03:44:56 PM
Personally, I would not assume anything, but, then, I guess my experience leads me to that...
Title: Re: issue with vibration at 60 mph
Post by: TexasT on July 27 2018, 08:44:06 PM
What are they using for camber and caster settings? Have you looked at the bushings? The pass side where the down pipe goes past is a common problem.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on August 02 2018, 05:58:57 PM
They say they have looked at everything.The y showed me the car on the hoist. Everything seems to be greased up nicely. I agree it does seem like it has to be related to something worn for it to shake that much. Will be a couple of weeks until I can report back again
Title: Re: issue with vibration at 60 mph
Post by: earlbrown on August 02 2018, 06:15:21 PM
I think the words 'checked' and 'looked at' are being used incorrectly in this instance.



A visual inspection is right at 0% effective in diagnosing, troubleshootin g, assessing, and repairing this condition.
Title: Re: issue with vibration at 60 mph
Post by: Top Speed on August 03 2018, 05:41:05 PM
So has the driveshaft been removed and re-balanced?
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on August 10 2018, 09:15:47 AM
Drive shaft has not been rebalanced. I hope to get it in for a better inspection of the front end in another week or so.
Title: Re: issue with vibration at 60 mph
Post by: Steve Wood on August 10 2018, 12:03:37 PM
What you really need to do is to look at the car yourself following some of the help that has been provided here, OR, find a car guy that will help you do the looking.  Beyond what I recall being posted, it could also be a wobbling damper, loose torque converter, or even a loose flex plate.  A bad tire, or a driveshaft problem is probably the most prevalent source of vibration, but, not the only one.

Most shops are pretty clueless on these cars so I can only see your future ownership experience being bad with a turbo Regal if you are not willing to learn for yourself.

These cars can drive you crazy even tho they are relatively simple compared to newer stuff.  It gets very expensive to allow shops with a lack of experience try to sort these cars out.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on August 16 2018, 04:57:50 PM
yes I am finding it is getting quite expensive trying to track done this issue and yes its hard to find anyone who knows these cars.  Its pretty tough to do much under the car without a hoist. I know most people make due with a jack and jack stands. I think we can rule out the wheels being the issue as I had them "road force" balanced today and still same problem. It only cost $30 so figured it was worth a shot. I have someone who is going to help me look at all the other things everyone has suggested but he wont be available until beginning of sept.
Title: Re: issue with vibration at 60 mph
Post by: earlbrown on August 16 2018, 07:57:15 PM
This is going to sound harsher than it really is, but from what I've read, you might want to get used to the idea of selling the car before it totally pisses you off.

   Right now you've got a repair that should be pretty cheap to fix.  And this issue doesn't snowball like an engine, fueling, or tune problem.  I can't imagine how bad it'll be when one of those problems shows up.


   Over the last couple decades, I've seen quite a few people buy this cars, throw money at problems without doing the free checks first, throw more money at it...    then throw more money at it  (often times the car's worse at this point).  Before it's over, the owner is thoroughly pissed off and dumps the car at a much larger loss than needed.    And keep in mind when I was seeing this a decade ago the cars were 'only' 20+ years old.

Title: Re: issue with vibration at 60 mph
Post by: rhturbo on August 20 2018, 03:07:03 PM
This is going to sound harsher than it really is, but from what I've read, you might want to get used to the idea of selling the car before it totally pisses you off.

   Right now you've got a repair that should be pretty cheap to fix.  And this issue doesn't snowball like an engine, fueling, or tune problem.  I can't imagine how bad it'll be when one of those problems shows up.


   Over the last couple decades, I've seen quite a few people buy this cars, throw money at problems without doing the free checks first, throw more money at it...    then throw more money at it  (often times the car's worse at this point).  Before it's over, the owner is thoroughly pissed off and dumps the car at a much larger loss than needed.    And keep in mind when I was seeing this a decade ago the cars were 'only' 20+ years old.


It has crossed my mind. I agree I am starting to get annoyed and quite frustrated. Two different garages with "licenced" mechanics and they cant figure out a vibration in the steering wheel  ? Having said that I don't believe this problem has anything to do with the fact this is a Grand National in which case having specific experience with this type of car is not likely to make it easier to diagnose. Either both mechanics who looked at it aren't very good (which is possible) or this problem is tougher to diagnose than most for some reason. This will get resolved eventually and when it does I will be sure to report back on the findings.
Title: Re: issue with vibration at 60 mph
Post by: TexasT on August 20 2018, 04:09:50 PM
You have to understand, nothing these"licensed" people work on is in the same realm as an eighties rwd gbody. Most probably weren't even born when the car was built. You really have to give up the idea that you cac take it somewhere and get it fixed. There just aren't mechanics out there to do it any more. Or if you can find one pay him well. As those are few and far between.

Title: Re: issue with vibration at 60 mph
Post by: earlbrown on August 20 2018, 07:09:05 PM


It has crossed my mind. I agree I am starting to get annoyed and quite frustrated. Two different garages with "licenced" mechanics and they cant figure out a vibration in the steering wheel  ? Having said that I don't believe this problem has anything to do with the fact this is a Grand National in which case having specific experience with this type of car is not likely to make it easier to diagnose. Either both mechanics who looked at it aren't very good (which is possible) or this problem is tougher to diagnose than most for some reason. This will get resolved eventually and when it does I will be sure to report back on the findings.


That's the thing. Mechanics don't work that like.  They go by flat rate, that's how they get paid.   If it takes them three times as long to fix something than the flat rate table indicates, they take a beating.   And you can't charge a customer 'clock hours' for head scratching.


This repair doesn't have a flat rate at all.  So basically, if you're lucky, they'll start off doing a flat rate job, like ''Replace all wheel bearings and seals'', or ''turn rotors/adjust bearings'', or ''replace tie rod ends''....   then charge you 'fairly' for the work.

...the downside is that the problem might not get fixed...   then you get to pay for more jobs that may or may not fix it until it's fixed, or you get fed up and take the car home with an empty wallet.


This is the kind of job that you need to do yourself.   If you replace the wheelbearings and turn the rotors for example, you now know for a fact you have new bearings and fresh rotors.   It might not fix the problem, but two years from now you'll know you have fresh bearings and rotors.

If you start tackling stuff yourself, eventually you'll solve the problem and have a list of stuff checked off your 30+ year old car.


If you go broke paying mechanics to play with your car (and using cheaper components and charging you more for them than quality parts), it's just not the same.

All that labor money could be put towards new universals, new bushings, new tie rod ends, new idler arm.....




......lay under the front of your car, grab ahold of the idler arm and yank it back and forth.   It can't be that easy.   Also, check your steering box for lots of slack.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on September 06 2018, 12:32:33 PM
Well it looks like my problem is a damaged (out of round) rim on rear of car. My rear rims are 15x8 and fronts are 15x7.  I guess I need to find a 15x8 somewhere or two 15x7's
Title: Re: issue with vibration at 60 mph
Post by: earlbrown on September 06 2018, 01:55:47 PM
I had a feeling it was going to be something stupid that could have been diagnosed in seconds.
Title: Re: issue with vibration at 60 mph
Post by: TexasT on September 06 2018, 03:33:58 PM
You would think that when you got the tires they might have mentioned the rim damage. So much for competent help at that place.
Title: Re: issue with vibration at 60 mph
Post by: rhturbo on September 06 2018, 06:15:13 PM
Anyone know anything about the quality of these rims ? Seller says exact replica of the originals. I am worried bot buying one and it doesn't match.
https://www.ebay.ca/itm/15-Inch-15x8-Alloy-Wheel-Rim-for-1981-1987-Buick-Regal-Grand-National/183159403349?hash=item2aa526b355:g:OUMAAOSwfaBawo Xf (https://www.ebay.ca/itm/15-Inch-15x8-Alloy-Wheel-Rim-for-1981-1987-Buick-Regal-Grand-National/183159403349?hash=item2aa526b355:g:OUMAAOSwfaBawoXf)

Title: Re: issue with vibration at 60 mph
Post by: Steve Wood on September 06 2018, 08:02:28 PM
Remember that I suggested to lift the rear end off the ground and crank it up, put it in gear and run the speed up to the vibration range to see if the shake was in the rear end?

Now, I can understand that you might not own jack stands, but, I cannot understand how any competent balancing would not have shown the out of round, wobble, or whatever.

My best advice is to never set foot in any of those shops that could not find the problem as they are fundamentally incompetent.
Title: Re: issue with vibration at 60 mph
Post by: reality on September 06 2018, 09:24:01 PM
Anyone know anything about the quality of these rims ? Seller says exact replica of the originals. I am worried bot buying one and it doesn't match.
https://www.ebay.ca/itm/15-Inch-15x8-Alloy-Wheel-Rim-for-1981-1987-Buick-Regal-Grand-National/183159403349?hash=item2aa526b355:g:OUMAAOSwfaBawo (https://www.ebay.ca/itm/15-Inch-15x8-Alloy-Wheel-Rim-for-1981-1987-Buick-Regal-Grand-National/183159403349?hash=item2aa526b355:g:OUMAAOSwfaBawo) Xf


Those are 15x8 , stock is 15x7.
Title: Re: issue with vibration at 60 mph
Post by: daveismissing on September 07 2018, 02:30:41 PM
Based on the upon the upc those are the Goodmark LQK rims.
I don't believe anyone else makes them, everyone sells them.
Title: Re: issue with vibration at 60 mph
Post by: TexasT on September 07 2018, 05:38:57 PM
Glad to hear you figured out the mystery.
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