1999 Suburban Shaking between 60-75mph

I had changed all pluges, wires, cap and roter which took care of the cylinder miss fire, but it did not take care of the shaking between 60-75mph. Had the tires roated 2X. I read that it could be the front axle being bad, but not willing to look at that just yet. It feel like it is not getting enough fuel. The fuel pump was replace about 3 months ago along with the external filter. I have not replaced the intake gasket yet, and have noticed the anitfreeze slowly leaking from the front. no water in the oil, mechanic said not to worry. Had the fuel injectors cleaned 2x. I would love to find out more before I take this in to be looked.

Test fuel pressure with a guagen

Do you feel the shake in the steering wheel or seat ? A vibration in a 5 - 10 mph range that goes away at other speeds is almost always an out of balance tire. Have any friends with a similar truck that you could swap all 4 tires for a quick test ?

I have the same problem with ours. Feels more like a sputtering. Clogged fuel filter is my guess as I remember changing it about 20k miles ago and the problem going away.

Do you feel the shake in the steering wheel or seat ? A vibration in a 5 - 10 mph range that goes away at other speeds is almost always an out of balance tire. Have any friends with a similar truck that you could swap all 4 tires for a quick test ?

I feel the whole car vibrating only at 60-73 mph. I had the tires balanced and rotated.

I have the same problem with ours. Feels more like a sputtering. Clogged fuel filter is my guess as I remember changing it about 20k miles ago and the problem going away.

I just had the fuel pump replaced 3 months ago. The fuel pump was replaced at 5-6 months ago. I will try that path again.

Thanks.

Test fuel pressure with a guagen

I will have the my mechanic test this, but I am not sure that is what it is only because it runs fine until I get to 60-73mph.

I just had the fuel pump replaced 3 months ago. The fuel pump was replaced at 5-6 months ago. I will try that path again.

Thanks.



Not the fuel pump but the inline filter.

Not the fuel pump but the inline filter.

I am sorry, I did replace the inline filter about 5-6 months ago with a fram filter. What a pain, it keep leaking. Finally i was able to get it to go on with out any leaking.

How often should I change this and why wouldn't it cause the same symptoms at speeds between 10 50mph?

Thanks for your reply.

I feel the whole car vibrating only at 60-73 mph. I had the tires balanced and rotated.

At this speed with foot off the gas put it in nuetral and see if anything feels different.

Hey guys, newb here, seems like I experience the same problem, but mine feels like a tire out of balance. Got 4 brand new tires and still has a vibration, maybe the guys at sears just did'nt take time to do it right, I don't know.

Hey guys, newb here, seems like I experience the same problem, but mine feels like a tire out of balance. Got 4 brand new tires and still has a vibration, maybe the guys at sears just did'nt take time to do it right, I don't know.

Glade to hear that someone else is having the same problem, but not to happy that we can figure this out. Did you replace the intake gasket yet? I was thinking that this might have an air leak in it. I love this truck, I just don't want to take it in to a mechanic to have them not figure it out. It feels like the tires but now I know it has to do with somthing else. I am replacing the fuel filter this weekend.

Let me know what you find out.

I change my fuel filter once a year or about 30,000 miles.

I just went through this and I know your frustration. Here's what I can tell you from my experience.

1) If the vibration is happening at only 60-75mph, then I don't think it's engine related I would expect engine issues to occur at a specific rpm, not mph.

2) Get the wheel's balanced. Many times, the place you bought them at will do this for free.

3) The u-joints on these vehicles are notoriously bad. If you haven't already replaced them, then you probably will need to. Simply feel if they are loose. If you have replaced u-joints or will be replacing them, be sure to get the rear drive shaft balanced. Getting the old u-joints out can create an imbalance in the drive shaft.

4) Replace brake drums. This was the biggest culprit in my situation. Most of the brakes sold nowadays are made in China. I believe that the Chinese manufacturers vary significantly in quality. I checked my new Chinese brakes with a dial indicator and found them to be 15 and 25 thousandths of an inch out-of -round when installed. After a week, the out-of-round increased by an additional 20 thousandths. The truck was also vibrating like crazy. I replaced the drums with a set of North American made ones and the pulsing during braking is gone, as well as the vibration has disappeared. The N/A drums cost me 3X what the Chinese units cost, but the peace of mind was worth it.

My Rant --- I'm not knocking the Chinese ... they have reduced the price of a lot of the things that we buy/use everyday. However, I don't think that the reduced cost comes entirely from cheaper labor. Most North American manufacturers are highly automated ... there's a lot less man hours that go into making the parts. I do believe that some of the cost savings comes from using inferior equipment and lower quality standards.

I ran into a similar situation with the air conditioning compressor that I ordered. It was a Chinese knock-off of the North American made Sanden. I had the Chinese unit installed and it made a loud whiring sound everytime it engaged. I got the vendor to send me another one ... same Chinese manufacturer ... it also made the same sound. I then insisted that the vendor send me an original Sanden ... which they did. Apart from the label, the unit was almost identical. The Chinese had definitely stolen the design ... but not the quality. I had the N/A made unit installed and it ran perfectly quiet as expected.

I will still buy Chinese made parts, but I will be very selective as to which ones.

I just went through this and I know your frustration. Here's what I can tell you from my experience.

1) If the vibration is happening at only 60-75mph, then I don't think it's engine related I would expect engine issues to occur at a specific rpm, not mph.

2) Get the wheel's balanced. Many times, the place you bought them at will do this for free.

3) The u-joints on these vehicles are notoriously bad. If you haven't already replaced them, then you probably will need to. Simply feel if they are loose. If you have replaced u-joints or will be replacing them, be sure to get the rear drive shaft balanced. Getting the old u-joints out can create an imbalance in the drive shaft.

4) Replace brake drums. This was the biggest culprit in my situation. Most of the brakes sold nowadays are made in China. I believe that the Chinese manufacturers vary significantly in quality. I checked my new Chinese brakes with a dial indicator and found them to be 15 and 25 thousandths of an inch out-of -round when installed. After a week, the out-of-round increased by an additional 20 thousandths. The truck was also vibrating like crazy. I replaced the drums with a set of North American made ones and the pulsing during braking is gone, as well as the vibration has disappeared. The N/A drums cost me 3X what the Chinese units cost, but the peace of mind was worth it.

My Rant --- I'm not knocking the Chinese ... they have reduced the price of a lot of the things that we buy/use everyday. However, I don't think that the reduced cost comes entirely from cheaper labor. Most North American manufacturers are highly automated ... there's a lot less man hours that go into making the parts. I do believe that some of the cost savings comes from using inferior equipment and lower quality standards.

I ran into a similar situation with the air conditioning compressor that I ordered. It was a Chinese knock-off of the North American made Sanden. I had the Chinese unit installed and it made a loud whiring sound everytime it engaged. I got the vendor to send me another one ... same Chinese manufacturer ... it also made the same sound. I then insisted that the vendor send me an original Sanden ... which they did. Apart from the label, the unit was almost identical. The Chinese had definitely stolen the design ... but not the quality. I had the N/A made unit installed and it ran perfectly quiet as expected.

I will still buy Chinese made parts, but I will be very selective as to which ones.


Wow...

Thanks for giving me the heads up. I didn't think it was the engine because it only does this at or past 60mph. I just replaced the in-line fuel filter, I had no problems with this one. I used AC Delco this time and it went on with out any trouble. I use a fram before and had trouble with it leaking around the threads.

I did have the seal from the transfer case to the drive shaft replaced because it was leaking, now it has started again. I will replace the rear drums with the American brand. The drive shaft and U-joints will be next along with a new transfercase seal. For all those reading this, I would replace all parts with AC Delco. I took the less expensive route and had nothing but problems. It looks like you can get this parts for a decent price out of the Summit Racing Mag.

Thanks for replying, I wasn't sure I was going to be able to fix this. I will keep you posted to the results.

Is this happen when there is a load on the engine? If so:

http://www.automotiveforums.com/vbulletin/showpost.php?p=3565554&postcount=67

The proper way to diagnose a vehicle vibration is to determine the frequency of the vibration. This will tell you the rotational group that is causing the vibration.
You can use a simple reed tachometer to find out this information
To determine the order of the vibration, use the following formula
Divide your vibration speed by 5, this will give you the frequency for a first order tire vibration (balance or out of round), then you can multiply your first order by 2 or 3 to determine the 2nd or 3rd order frequency.
To find a driveline vibration, divide your vibration speed by 5, then multiply the answer by your axle ratio, this will give you the 1st order vibration, then to find out if it is a u-joint, double your first order answer.
It sounds complicated, but it is rather simple.
Lets say you have a vibration at 65 mph.
65 divided by 5 = 13 this would be a balance or out of round issue
13x2= 26 this would be a second order vibration
13x3=39 this would be 3rd order

driveline
13x axle ratio, lets say 3.43 would equal 44.5 hz. this would be an out of balance driveshaft or related component
to find a u-joint, multiply 44.5 X 2= 89

Hey GMMerlin, that's some pretty good background info but most do-it-yourselfers won't be able to get a reading on the vibration frequency.

One interesting point that you make is that a driveshaft imbalance will give you a higher frequency vibration than an imbalance at the wheels. The fact that we're dealing with less weight and a smaller circumference in the driveshaft, the amplitude would most likely be less also.

Testing the u-joints is easy. There are 4 bolts ... 5 -10 minutes and the driveshaft is off. Just feel if the u-joints are without play and rotate freely. The original u-joints won't have a grease fitting ... the aftermarket replacements most likely will ... be sure to add grease if there is a nipple.

Testing brake drum imbalance is not feasible for the home mechanic. If you have a dial indicator, you can measure out-of-round by mounting the drum onto the hub backwards. An easier test would be to hold the release lever and apply the parking brake (USE CAUTION TO NOT LOSE CONTROL OF VEHICLE). If the the drums are out-of-round you will feel a pulsing deceleration. Out-of-round does not necessarily equate to out of balance, but it does indicate that the drums aren not exactly perfect.

In my case, one thing that made me suspicious of the drums is that I looked at 4 of them all from the same Chinese manufacturer. Each of them had the exact same sized counter weight welded on. I was skeptical that all 4 could have been manufactured when the exact same imbalance. I looked at 2 North American made drums and they had different sized weights.

Why couldn't a DIY get a frequency reading. A reed tac is a simple device that anyone can use, just drive at the speed you feel the vibration the stongest and look at what reed is shaking the most..that is the frequency of the vibration.
Next do the math and you have the component rotational group that is the source of the vibration.
If you have a tire speed vibration, you must take in account all the components that rotate at that speed (tire, wheel, drum, rotor, axle, hub) and then eliminate the possible causes.
The faster a component rotates, the highr the frequency, that is whay a tire will have 12 hz while a driveshaft would be in the 45 hz range.
Amplitude is the measure of how stong the vibration is.

Why couldn't a DIY get a frequency reading. A reed tac is a simple device that anyone can use, just drive at the speed you feel the vibration the stongest and look at what reed is shaking the most..that is the frequency of the vibration.
Next do the math and you have the component rotational group that is the source of the vibration.
If you have a tire speed vibration, you must take in account all the components that rotate at that speed (tire, wheel, drum, rotor, axle, hub) and then eliminate the possible causes.
The faster a component rotates, the highr the frequency, that is whay a tire will have 12 hz while a driveshaft would be in the 45 hz range.
Amplitude is the measure of how stong the vibration is.

Merlin: I've been following this post just for info reasons. Now you've got me interested in the "reed tach". If you could tell me what it is, how to make it, etc maybe I could figure out some "vibs" from the old Vandura.............Steve

Here is what I am talking about
http://dlwilliamscompany.com/sticht.html
I used to use one of these years ago for diagnosing vehicle vibrations before we started using an electronic one.
Also Briggs and Statton used to have a simple rpm/hz gage to set idle on lawnmowers that worked good too.

[quote=Blake1]Wow...

Thanks for giving me the heads up. I didn't think it was the engine because it only does this at or past 60mph. I just replaced the in-line fuel filter, I had no problems with this one. I used AC Delco this time and it went on with out any trouble. I use a fram before and had trouble with it leaking around the threads.

I did have the seal from the transfer case to the drive shaft replaced because it was leaking, now it has started again. I will replace the rear drums with the American brand. The drive shaft and U-joints will be next along with a new transfercase seal. For all those reading this, I would replace all parts with AC Delco. I took the less expensive route and had nothing but problems. It looks like you can get this parts for a decent price out of the Summit Racing Mag.

Ok, replaced the in-line fuel filter, and rear brake drums. Talked with the guy a Napa he said it is possible the front wheel berrings could be going, I checked and no movement with the tire up and down. As I looked I noticed that the tires on the front both have a small cupping edge on both sides of the tire. I am sure the problem is causing this to happen. I had the front end looked at and they said it was all tight. (i don't feel like they really looked that good).

Next step is going to get the tires rebalenced and purchase both new front roters and front shocks. ( I have not replaced the front shocks since 1999).

I will also be getting a front end alignment.

Could it be the tie rods, or any of the front end parts causing this?

I don't want to replace the front hubs, that is going to be a project I can't do.

[quote=Blake1]Wow...

Thanks for giving me the heads up. I didn't think it was the engine because it only does this at or past 60mph. I just replaced the in-line fuel filter, I had no problems with this one. I used AC Delco this time and it went on with out any trouble. I use a fram before and had trouble with it leaking around the threads.

I did have the seal from the transfer case to the drive shaft replaced because it was leaking, now it has started again. I will replace the rear drums with the American brand. The drive shaft and U-joints will be next along with a new transfercase seal. For all those reading this, I would replace all parts with AC Delco. I took the less expensive route and had nothing but problems. It looks like you can get this parts for a decent price out of the Summit Racing Mag.

Ok, replaced the in-line fuel filter, and rear brake drums. Talked with the guy a Napa he said it is possible the front wheel berrings could be going, I checked and no movement with the tire up and down. As I looked I noticed that the tires on the front both have a small cupping edge on both sides of the tire. I am sure the problem is causing this to happen. I had the front end looked at and they said it was all tight. (i don't feel like they really looked that good).

Next step is going to get the tires rebalenced and purchase both new front roters and front shocks. ( I have not replaced the front shocks since 1999).

I will also be getting a front end alignment.

Could it be the tie rods, or any of the front end parts causing this?

I don't want to replace the front hubs, that is going to be a project I can't do.

Ok, replaced the in-line fuel filter, and rear brake drums. Talked with the guy a Napa he said it is possible the front wheel berrings could be going, I checked and no movement with the tire up and down. As I looked I noticed that the tires on the front both have a small cupping edge on both sides of the tire. I am sure the problem is causing this to happen. I had the front end looked at and they said it was all tight. (i don't feel like they really looked that good).

Next step is going to get the tires rebalenced and purchase both new front roters and front shocks. ( I have not replaced the front shocks since 1999).

I will also be getting a front end alignment.

Could it be the tie rods, or any of the front end parts causing this?

I don't want to replace the front hubs, that is going to be a project I can't do.

I just went through this and I know your frustration. Here's what I can tell you from my experience.

1) If the vibration is happening at only 60-75mph, then I don't think it's engine related I would expect engine issues to occur at a specific rpm, not mph.

2) Get the wheel's balanced. Many times, the place you bought them at will do this for free.

3) The u-joints on these vehicles are notoriously bad. If you haven't already replaced them, then you probably will need to. Simply feel if they are loose. If you have replaced u-joints or will be replacing them, be sure to get the rear drive shaft balanced. Getting the old u-joints out can create an imbalance in the drive shaft.

4) Replace brake drums. This was the biggest culprit in my situation. Most of the brakes sold nowadays are made in China. I believe that the Chinese manufacturers vary significantly in quality. I checked my new Chinese brakes with a dial indicator and found them to be 15 and 25 thousandths of an inch out-of -round when installed. After a week, the out-of-round increased by an additional 20 thousandths. The truck was also vibrating like crazy. I replaced the drums with a set of North American made ones and the pulsing during braking is gone, as well as the vibration has disappeared. The N/A drums cost me 3X what the Chinese units cost, but the peace of mind was worth it.

My Rant --- I'm not knocking the Chinese ... they have reduced the price of a lot of the things that we buy/use everyday. However, I don't think that the reduced cost comes entirely from cheaper labor. Most North American manufacturers are highly automated ... there's a lot less man hours that go into making the parts. I do believe that some of the cost savings comes from using inferior equipment and lower quality standards.

I ran into a similar situation with the air conditioning compressor that I ordered. It was a Chinese knock-off of the North American made Sanden. I had the Chinese unit installed and it made a loud whiring sound everytime it engaged. I got the vendor to send me another one ... same Chinese manufacturer ... it also made the same sound. I then insisted that the vendor send me an original Sanden ... which they did. Apart from the label, the unit was almost identical. The Chinese had definitely stolen the design ... but not the quality. I had the N/A made unit installed and it ran perfectly quiet as expected.

I will still buy Chinese made parts, but I will be very selective as to which ones.


Ok, replaced the in-line fuel filter, and rear brake drums. Talked with the guy a Napa he said it is possible the front wheel berrings could be going, I checked and no movement with the tire up and down. As I looked I noticed that the tires on the front both have a small cupping edge on both sides of the tire. I am sure the problem is causing this to happen. I had the front end looked at and they said it was all tight. (i don't feel like they really looked that good).

Next step is going to get the tires rebalenced and purchase both new front roters and front shocks. ( I have not replaced the front shocks since 1999).

I will also be getting a front end alignment.

Could it be the tie rods, or any of the front end parts causing this?

I don't want to replace the front hubs, that is going to be a project I can't do.

had the same issue with my 96 this time last year. i did most of the same test and checks you did also. i finaly had the tires replaced and poof problem gone. good luck. mark.

Has anybody come up with any updated results for this problem? I got on the highway the other day, and once I got to about 60 mph, the steering wheel & front end started shaking so bad, I thought I'd have to pull over!

I've experienced this before at about 45-50 mph, and was able to get it to stop by turning the steering slightly, but this time was the absolutely WORSE it's EVER been!

I just need to know what to ask my mechanic to check, which scares me because of COST!

My son has a 50,000 mile 2004 Silverado and was telling me about a steering problem many of these trucks have as a result of a faullty design. The inner and outer shafts of the collapsible steering column can wear prematurely, causing looseness and vibration felt through the stering wheel.

Don't know if your 99 has the same components, but thought I'd pass it on. There's a service bulletin out on this topic, ask your dealer.

Be very careful with this one. I just went throught the shaking thing with mine - same year/model/make as yours. One section of the universal joint turned out to be almost completely sheared off. I'm told that it was quite possible this could have caused my drive shaft to drop out completely and send the vehicle flipping top over end in which case we could easily have been killed or severly injured. It's apparently nothing to be messed with. CHECK IT ASAP!

Thank you, and I will get it checked!!
Glad you're alright!!

I've been working the same problem. It turns out to be a combination of things. The pitman arm was worn so replaced. Already there so I did the idler as well. One front wheel bearing was maladjusted and needed tightening. The bearing was fine, established by cleaning, inspection and repacking. Left rear tire not balanced properly.

Inspection of the universal joints shows they are fine. A note on U-joints, the front one is the dangerous one as a failure there could cause the driveshatft to drop onto the pavement and if it falls in a hole, will catch and lift the vehicle's rear end into the air. If the rear one fails, it will drop onto the pavement and drag.

Just FYI - I had the whole steering system pretty much replaced about a year and a half ago; the pitman arm, gear box, well, just about everything accept the steering column itself. The reason I did that was because my Burb was suddenly jerk pulling, especially around corners. It felt like there was an invisible person in the car with me tugging on the steering wheel. What it ultimately turned out to be was a computer chip in the power steering unit. Oh well, at least I now have all new steering stuff and I'm safe with that. I got the vehicle aligned and wheels balanced after all of that work. Then at 180k miles I finally had to do my first engine servicing. Right after that it started with the shaking thing as you described. I told my shop about it and they checked the engine out again to see if maybe a spark plug had come loose or something, but that was all fine. They said they couldn't find anything wrong. I continued to drive though I knew something was really wrong. I barely made it back to the shop one day and said to them, "Look, this thing is sputtering now when I step on the gas and shaking horribly." When I came back to pick it up, they showed me the U-joint. My guy at the shop told me in 27 years of working on vehicles he had never seen one in that bad shape. He said either I was very lucky or someone was watching over me big time.