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1999 GMC Sierra 5.3 Extended Cab RWD. A long time ago I talked with Eric about this. Okay, I’ve been dealing with this problem ever since I got the truck in 2010 mostly because money is tight and I don’t want to throw parts at it. The main problem is on some freeway surfaces, I get an intense vibration/shaking between 60 and 70 miles per hour. It will usually stop after 70, but it can still be felt slightly. The shaking can be felt through the entire vehicle and the steering wheel. It feels like someone is grabbing you and shaking you 4 or 5 times per second. I haven’t gone through everything in the service manual, but I will tell you what’s been done.
I’m on my 2nd set of tires. Original tires did this – had them rebalanced several times. I bought a new set of BFGs – basically the same thing – balanced several times. I got the tire shop to replace the BFGs with Michelins (The most expensive tire for this truck) – same thing. Balancing doesn’t effect it very much.
I’ve taken the truck up to 75 MPH and then put the truck into neutral. Coasting down through the problem range – problem is still present.
The shocks are Bilstein heavy duty – perhaps a little too stiff, but all the shocks did was make the shaking/vibrating more noticeable. Ride can be a little rough though.
I’ve had two alignments within the past year. A GM mechanic I spoke with blames the alignment – this doesn’t make sense to me.
I’ve retorqued the ball joint nuts, lower control arm bolts, power steering rack bolts, tie rod ends, sway bar end links.
Ball joints do not appear to have any play when a giant pry bar is placed underneath the supported tire.
Truck has a two piece drive shaft. There doesn’t seem to be any play in the center bearing or the u-joints.
Some things I’ve also noticed: if I have an extra four or five hundred pounds in the truck (cab or bed) the vibration is greatly reduced or is eliminated. I do not think I am suffering from the infamous “frame beaming.” This shaking is much too intense.
I haven’t had a change to get under the truck to measure the suspension per the service manual but I found this interesting.Measuring from the top of the tires diagonally to the fender I get different measurements (my 1990 regular cab is basically the same side to side).
Front left: 5 and 1/16 inches
Front right: 4 and 3/4 inches
Rear left: 6 and 1/4
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Wheel weights?
http://www.youtube.com/watch?v=8Gx_hJ3NGKoIf you had the balancing done and they used their own lugs instead of yours maybe that might not show the issue. Can’t imagine anyone would make that mistake twice but your issue sounds like a simple weight problem. Issue with lug nuts is sometimes one is heavier than the others (wheel lock). That’s probably not going to be your issue but it’s worth mentioning.
I know my vibration issue has to do with low compression. If you can’t figure out what’s causing it maybe get a compression test? You would certainly feel it at low speeds more. Then again you’ve taken it to multiple shops and they can’t figure it out and that’s what they get paid to do. So it’s time to think outside the box.
All the weights are on there. Their machines don’t use lug nuts – it’s a hunter machine that has a main shaft and they screw on an attachment that centers the wheel onto the main shaft. Ah… I love British Top Gear….
Compression is good, all cylinders are between 185 and 190psi.
I plan on doing ball joints on it next. Especially since it feels like the front end is getting sloppier by the day. The left front ball joint will make a “knock” type noise if I hit a bump and sometimes during lateral movement.
As for the clunk that I mentioned earlier it is something in transmission or driveline because I do not get the clunk if I stop the truck in neutral. Not sure what it is yet, but maybe the old u-joints were hiding a problem I wasn’t aware of.
How does the trans fluid look? and when was the last time it was serviced?
If you do the ball joints soon, i would recommend doing a “How To…” for the forums members C8-)
The fluid wasn’t too pretty when I got the truck a year and a half ago. I swapped out all the fluid and changed the filter. Sometimes it will shift a little weird, but it works well for 120k miles and lack of fluid change. It’s still pretty red right now.
Haha, yeah, I’ll be “TimTheCarGuy”
If everything seems normal and it’s been checked and rechecked then the issue has to be coming from somewhere else or you missed something in the driveline. Have you had fuel pressure checked? Fuel filter changed? Haven’t heard one mention about fuel pressure. At highway speeds think about what has to work harder. It’s certainly not the suspension that has to work harder. Coolant, engine temp, and injector cycles would raise. If it doesn’t have enough pressure or some part of the fuel system can’t get the injectors to those higher duty cycles then the engine will run rough. That’s my thinking anyway. I could be way off and that’s fine, just giving you something else to think about since it seems everything else has been covered.
Dreamer it’s not going to be a bent crankshaft or transmission (torque converter) because those would be obvious at low speeds and have other really obvious issues.
Quoted From djdevon3:
If everything seems normal and it’s been checked and rechecked then the issue has to be coming from somewhere else or you missed something in the driveline. Have you had fuel pressure checked? Fuel filter changed? Haven’t heard one mention about fuel pressure. At highway speeds think about what has to work harder. It’s certainly not the suspension that has to work harder. Coolant, engine temp, and injector cycles would raise. If it doesn’t have enough pressure or some part of the fuel system can’t get the injectors to those higher duty cycles then the engine will run rough. That’s my thinking anyway. I could be way off and that’s fine, just giving you something else to think about since it seems everything else has been covered.
Dreamer it’s not going to be a bent crankshaft or transmission (torque converter) because those would be obvious at low speeds and have other really obvious issues.
Who said anything about it being a crankshaft issue or a torque converter issue???
Crankshafts don’t usual bend, its the thrust plate that likes to fail, that more so with manual trans vehicles.
If he suspects a misfire, he would need to stress test the ignition system. However the misfire monitor should pick that up and store a pending code then to a hard fault.
Hard shifting in the trans can be caused by lack of lubrication, issues with the valve body, or issues with shift solenoids. Those usually set off again a CEL. Thats why i asked about the trans fluid color and when it was last serviced.
When torque converters fail, it usually feels like the trans is slipping.
Idle issues can also cause hard shift, again IF this is the symptom the OP is having. Worn motor and trans mounts can also cause a clunking noise.
Again, i have no clue where the crankshaft or torque converter comment came from?
Wow new info. Well if you are sure the driveline is good and you are 100% sure that there isn’t a tire or tire balance problem it might be someting in the transmission if it only happens in a paticular gear. If it were an engine performance issue I would think at the very least you would have a check engine light or something to go along with it, come to think of it if it was a transmission issue this would also be possible. Did we ever look into the rear diff on this? If so what was found? I can’t stress enough how vibrationst at speed are often balance related, loose suspension parts or wheel bearings won’t cause a vibration like that, they might make it seem worse but they are not normally the cause. Try rotating the tires just for the heck of it to see if the vibration changes or goes away. A bad tire can balance out but still have an issue that causes a vibration at speed. I’d like to keep this simple, lets not overcomplicate it as is often the tendency in a case like this.
Sorry Dreamer thought you were going for a torque converter issue and I jumped to anything the might wobble.
The clunk when accelerating from a stop sounds like the slip yoke where it slides into the transmission. You need to grease the splines before putting it back into the back of the transmission (or transfer case on 4×4 models). If it’s dry the yoke will bind on the output shaft and give a clunk and a bit of a moan type noise.
Quoted From Shaun_300:
The clunk when accelerating from a stop sounds like the slip yoke where it slides into the transmission. You need to grease the splines before putting it back into the back of the transmission (or transfer case on 4×4 models). If it’s dry the yoke will bind on the output shaft and give a clunk and a bit of a moan type noise.
Interesting as ive never heard or seen of the yoke ‘binding’ before…..
Quoted From dreamer2355:
Interesting as ive never heard or seen of the yoke ‘binding’ before…..
Yup, very common for the newer GM trucks, there was actually a TSB on them I believe. The yoke won’t slip as it’s supposed to causing that clunk/noise when coming to a stop fairly quickly or accelerating.
Shaun_300 was right about the yoke, I actually did my own research and found this out. On mine, the middle slip yoke has a zerk fitting. I pumped a bunch of grease in there, and now it’s basically gone. It probably got squeezed out when it got compressed all the way. There wasn’t any grease on the transmission one, but if I get a clunk again, I read you can grease that too with the right grease so it doesn’t get washed out by trans fluid.
Funny DJDevon should mention the fuel pressure. I’ve been also chasing a slight lack of power/ aftermarket exhaust sounding weak. I’m 99% sure it’s the regulator. Fuel pressure with the truck running is about 47-48psi. It should be around 58psi, 55psi minimum. If the engine is revved the fuel pressure will drop at least another 5psi. If I disconnect the vacuum line and plug it, fuel pressure goes up to 58 exactly and the engine seems to run better and sound healthier. The fuel filter was changed last year, FYI.
Eric, I will try the tires again, they are due for a rotate/rebalance anyways. I just really doubt the tires since this is my third set. I think have 3 sets of bad tires is 1 in a million. One of the teeth from the spider gears had piece missing and it was on the magnet. I cleaned up everything and put in some new diff fluid. So far so good.
Well, I plan on doing ball joints, bushings and upper control arms (not much more expensive than the ball joint) on the weekend. I think the left ball joint is definitely going out, it’s starting to click/pop even more. So we’ll see if that fixes it. Maybe I will bust out the video camera.
Honestly it’s not a vibration; I think a more accurate description is a violent death shake. I’m doing some training for a new job and I have to drive over a rather uneven/bumpy stretch of freeway for about a mile or so, and every time I feel like my brain will get shaken out of my head. Depending on how the freeway surface is I will get a strong shake from 70 on up (not always 60-70), but if the road is bumpy – hold on. It shakes like if you were driving over cobblestone during an 8.0 earthquake.
Quoted From Shaun_300:
Yup, very common for the newer GM trucks, there was actually a TSB on them I believe. The yoke won’t slip as it’s supposed to causing that clunk/noise when coming to a stop fairly quickly or accelerating.
Thanks for this tip. Its noted down S:)
Just an FYI, I had tires rotated and rebalanced today. Same thing as always – virbration/shake.
Shaun, what grease do you guys use on the slip yoke that goes into the transmission? Someone told me vaseline, but i would think there has to be a suitable grease that won’t wash out with the tranny fluid.
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