Vibration - Engine under load

[mubai]

Vibration happens when?:
1. 30 - 50 mph - feels erratic, not consistent vibration. Almost like feeling a kick.
2. 30 - 50 mph - Worse when accelerating, actually my main issue with this complaint.
3. 50 - 75 mph - minor vibration while accelerating
4. 75-90 mph - smooth as butter, while accelerating (truck doesn't coast at 75-90mph, you gotta keep the foot on the right pedal )
5. Any speed - no change in vibration when in neutral
6. Parked - no vibration

Completed
1. Cleaned throttle body
2. No SES
3. Tie rods changed
4. Tires rotated and balanced 3 times in a month (NTB unlimited rotation, alignment and balancing)
5. Tires aligned
6. Tire pressure good
7. Tires checked for any anomalies
8. Tires have about 4000 miles
9. Changed front U-Joint

Any other suggestions would help, preferably before it gets any colder. Cause it's nowhere near awesome to work on your truck when it's below freezing.

 

[gmcman]

The problem is you live in Philly and likely route for the eagles. Owning a vehicle under these conditions will cause you alot of grief. I say, pack up your stuff, and move south. When you do, your voy will surely treat you better.

Sorry, had to make post #666 worthwhile.


Ok, back to business. You said you changed the front U-joint, how long after this did the vibration happen..or was it before? If it was before, are you absolutely sure you installed the front yoke in the same orientation as when you removed it.

Did you perform the U-joint change yourself?

 

[CaptainXL]

Hey there mubai.

Any noises other than vibration? Grinding? Growling? Humming? etc..

Does it get worse when turning while accelerating? Does the vibration get worse or better when in 4WD?

Do you feel the vibration in the seat or steering wheel?

 

[mubai]

The problem is you live in Philly and likely route for the eagles. Owning a vehicle under these conditions will cause you alot of grief. I say, pack up your stuff, and move south. When you do, your voy will surely treat you better.

Absolutely agree, that's why I'm a Steelers fan. As long as we have a team and not everyone is out on injuries, I'll be a fan. Grew up in Pittsburgh, moved out to Philly for work.

Ok, back to business. You said you changed the front U-joint, how long after this did the vibration happen..or was it before? If it was before, are you absolutely sure you installed the front yoke in the same orientation as when you removed it.

Did you perform the U-joint change yourself?

Vibration was before the U-joint change. I changed it in hopes that it was the issue, but that didn't work.

Hey there mubai.
Any noises other than vibration? Grinding? Growling? Humming? etc..

Yo CaptainXL, how's it going?

No noises, just the stupid erratic vibration.

Does it get worse when turning while accelerating? Does the vibration get worse or better when in 4WD?

I don't remember it getting worse while turning and accelerating, I can test tomorrow. It's the same vibration in 4WD, I did try that.

Do you feel the vibration in the seat or steering wheel?

I would say both, but definitely more in the seat.

 

[gmcman]

Reason I ask if you changed the joint yourself, did you heat the joint before you pressed it out? I know you said it was vibrating before but wanted to ask.

It almost sounds like it could still be a driveshaft issue so how does the rear joint feel? You could try to move it in the yoke or just pull it out and inspect.

How are the axle bearings and front hub and bearings?

 

[CaptainXL]

Just a thought but if the uJoint was replaced but the driveshaft wasn't indexed then that might cause the issue.

 

[mubai]

Reason I ask if you changed the joint yourself, did you heat the joint before you pressed it out? I know you said it was vibrating before but wanted to ask.

It almost sounds like it could still be a driveshaft issue so how does the rear joint feel? You could try to move it in the yoke or just pull it out and inspect.

How are the axle bearings and front hub and bearings?

I just used some PB Blaster and a socket and press to get them out. No heat.

Front hub and bearings are good. I replaced them a couple years ago because of growling issues.

I'm not sure how to check the axle bearings. Do I just put the rear tires up on jack stands and spin and listen for noise?

I'll checkout the rear shaft, but not sure how to inspect it.

Just a thought but if the uJoint was replaced but the driveshaft wasn't indexed then that might cause the issue.

If that's the issue, how would I go about correcting that issue?

These are good questions, really appreciate the help.

 

[CaptainXL]

If that's the issue, wow would I go about correcting that issue?

You would want to disconnect and rotate the driveshaft 180 degrees. Reconnect and then retest. I meant that basically it could be off balance and it wasn't installed in the same relation to the pinion shaft when put back together.

 

[gmcman]

Do you have any salvage yards near you? Perhaps you could go by and ask to try a shaft and see if it solves your issues. Maybe even swap it out in the parking lot, only takes 5 min. Just take some steel wool, like 000 or 0000 and clean off the front yoke where it rides in the transfer case to not damage the seal.

What was the order you started your fixes after the vibration started? Did the vibration always stay the same throughout the diagnosis?

 

[gmcman]

I just used some PB Blaster and a socket and press to get them out. No heat.

Front hub and bearings are good. I replaced them a couple years ago because of growling issues.

I'm not sure how to check the axle bearings. Do I just put the rear tires up on jack stands and spin and listen for noise?

I'll checkout the rear shaft, but not sure how to inspect it.



If that's the issue, wow would I go about correcting that issue?

These are good questions, really appreciate the help.

If you installed the front yoke incorrectly, you will need to press the joint out again and rotate it 180 deg.

Front bearings, jack up the lower control arm and grab the top and bottom of the tire, forcefully shake the tire back and forth and try to hear and or feel any movement, like a thunk. Do this on all 4 corners.

What bearings did you put in the front?

You would want to disconnect and rotate the driveshaft 180 degrees. Reconnect and then retest. I meant that basically it could be off balance and it wasn't installed in the same relation to the pinion shaft when put back together.

This is definately something to try first before you start pressing joints, if you need to.

 

[gmcman]

I just used some PB Blaster and a socket and press to get them out. No heat.

Was it ridiculously difficult to press out the joint? I want to assume it was. Without heating the yoke you could have possibly bent the ears on the shaft.

Wanted to add, the reason for the heat is to melt the epoxy holding the joints in place. I re-read you used a press so may have been fairly easy.

 

[mubai]

You would want to disconnect and rotate the driveshaft 180 degrees. Reconnect and then retest. I meant that basically it could be off balance and it wasn't installed in the same relation to the pinion shaft when put back together.

OK, understood. I will give that a go, pretty easy test.

Do you have any salvage yards near you? Perhaps you could go by and ask to try a shaft and see if it solves your issues. Maybe even swap it out in the parking lot, only takes 5 min. Just take some steel wool, like 000 or 0000 and clean off the front yoke where it rides in the transfer case to not damage the seal.

What was the order you started your fixes after the vibration started? Did the vibration always stay the same throughout the diagnosis?

Vibration started for a while and I thought it was my tires, they were cupping (may03lt) confirmed they were cupped. So, I got new tires (balanced 3x, aligned and rotated), and the flopping sound when driving slowly stopped. However, the other vibration (30mph - 50mph) was still going on. There was some play in the front right tie rod, I had both replaced (reminds me, I gotta post a pic of the old one to show how mangled the nut got when the mechanic replaced it). No change. Then my water pump blew up, had to go to some shady garage in Baltimore, but they did a fair job. They also noted that my front U-Joint had play in it, so I bought the part and replaced it myself. No change.

I'll have to check around on salvage yards, don't know any off hand. Could the front shaft splines be worn enough to cause that vibration?

 

[gmcman]

Could the front shaft splines be worn enough to cause that vibration?

Probably if severly worn but I want to say I doubt they are that worn....not that it's not worth checking.

Have you checked the transfer case fluid level?

If you make it to the Northern Va area give me a shout, I have a spare driveshaft you can test.

 

[CaptainXL]

OK, understood. I will give that a go, pretty easy test.

Yeah I double checked by usual sources and most of the time if the vibration is felt in the seat then its the drive-shaft.

 

[mubai]

If you installed the front yoke incorrectly, you will need to press the joint out again and rotate it 180 deg.

OK will do, after I try the rotate 90 and try again.

What bearings did you put in the front?

Sorry, I don't remember the brand, but I didn't try to put in new bearings. I replaced the whole hub/bearing.

Front bearings, jack up the lower control arm and grab the top and bottom of the tire, forcefully shake the tire back and forth and try to hear and or feel any movement, like a thunk. Do this on all 4 corners.

On the rear should I jack up the truck by the differential and try the tire shake?

 

[mubai]

Probably if severly worn but I want to say I doubt they are that worn....not that it's not worth checking.

Have you checked the transfer case fluid level?

Probably if severly worn but I want to say I doubt they are that worn....not that it's not worth checking.

Have you checked the transfer case fluid level?

If you make it to the Northern Va area give me a shout, I have a spare driveshaft you can test.

Ah that's really cool man, thanks for the offer. I drive to Baltimore twice a week, but I'm not sure if I'll make it to NVA.

 

[gmcman]

OK will do, after I try the rotate 90 and try again.


Sorry, I don't remember the brand, but I didn't try to put in new bearings. I replaced the whole hub/bearing.

Yeah, that's what I was referring to, the whole assembly. More cases than usual are people having issues with the cheaper bearings...ie, around $60-90 range but not saying you are cheap if you did this. Some keep on going but wanted to ask.




On the rear should I jack up the truck by the differential and try the tire shake?

Yeah that's what I do.

Also, just make sure all your diff fluids are topped off, including the transfer case.

 

[mubai]

Yeah, that's what I was referring to, the whole assembly. More cases than usual are people having issues with the cheaper bearings...ie, around $60-90 range but not saying you are cheap if you did this. Some keep on going but wanted to ask.

Yeah, gotcha, no offense. I know what you're saying.


Also, just make sure all your diff fluids are topped off, including the transfer case.

Will do. The diffs were checked recently, I'll just have to check the TC.

OK, I have plenty of work to do! Thanks!

 

[mubai]

OK, so I took off the front driveshaft, rotated the thingy (technical term, hopefully everyone understands it), 180 degrees, aligned up the U-joints and put the metal straps back on. No difference.

I had both rear wheels on jack stands and try to get my wife to run it in drive to see if I could see the wobble (front or rear driveshaft). Let's say, she respectfully declined.

Question, do the front and rear drive shafts rotate when the vehicle is in neutral going down a hill? How about in drive when coasting down a hill? The vibration does subside a lot when I'm not accelerating.

 

[The_Roadie]

Neutral or drive makes no difference if you're in 2HI mode. The rear driveshaft is turned by the action of the rear diff. The front driveshaft is free to turn or not turn, but my experience is that it doesn't turn because its seal friction is higher than the force trying to turn it. But yours may turn - just without any torque on it, so there's very little chance it's the source of vibration. I'm still thinking CV joints.

What happens in the front differential is sort of interesting because of the splined disconnect on the passenger side. If the front diveshaft doesn't turn, then the gear carrier inside the front diff doesn't spin. But the driver's side CV shaft is always connected, and spins whenever the vehicle is in motion. So the CV shaft is connected to an inner gear, which turns the carrier's spider gears, which spins the passenger side inner gear, which is connected to the intermediate shaft that goes through the tube cast into the oil pan. So in essence the intermediate shaft is rotating BACKWARDS from the CV shaft on the other side of the splined disconnect. If you suddenly engage A4WD or 4HI while you're driving, which is allowed by the manual and the TCCM doesn't lock it out, you're asking the splined disconnect to instantly connect the intermediate shaft to the passenger CV shaft and that starts the intermediate shaft turning opposite to the way it was just turning. And then the front differential carrier has to start spinning, and that drives the front driveshaft to rotate just the same way the rear driveshaft has always been rotating. My advice - don't engage A4WD or 4HI while going down the road at any speed unless you're desperate for traction.

 

[mubai]

Took it up to my local garage. Lift and heat, can't beat it. Problem was the rear drive shaft, rear U-Joint. The C-clip was out, but it was still hanging on by some miracle, decent amount of play in it. Replaced the rear U-joint and all is smooth again.

The erratic vibrations at all speeds has stopped. 30MPH is as smooth as 65MPH. The mechanic did say the front drive shaft might need to be replaced, since there was some play on transfer case side. He said, it's not a big deal now, but if you notice vibration picking up, then check that first. These guys at my local garage are pretty cool...

Also, big ups to everyone here who offered valuable advice.

While it was on a lift, changed the differential and transfer case fluids as well. Created my first YouTube video showing some of the fluid draining and location.

Auto Trak II Transfer Case Fluid - $6.97 each (2)
Royal Purple Gear Oil 75w-90 - $16.79 each (3)

[video=youtube;fePvtc51l0g]http://www.youtube.com/watch?v=fePvtc51l0g[/video]

 

[gmcman]

Awesome....same with mine. I replaced the U-Joint and the clip was missing. Glad you found the culprit.

OK, so I took off the front driveshaft, rotated the thingy (technical term, hopefully everyone understands it), 180 degrees, aligned up the U-joints and put the metal straps back on. No difference.

Well, unfortunately the front was not the shaft we were referring to for you to rotate 180 deg. I would put it back the way it was since driveshafts and their components like to live in the same orientation if you remove them. The front isn't as critical as the rear since it doesn't receive constant torque but for peace of mind it's prob best to change it back.

 

[CaptainXL]

Look closely when the diff is drained you will see at first the silvery color metal come out that was sitting at the bottom. The fluid changes color a second later. The cover should have been removed to inspect the gears and clean the magnet.

 

[mubai]

I would put it back the way it was since driveshafts and their components like to live in the same orientation if you remove them. The front isn't as critical as the rear since it doesn't receive constant torque but for peace of mind it's prob best to change it back.

Yeah, I'm happy that it's fixed. Went for a 30 mile drive, got the truck up to 75MPH, smooth all the way through. I may change out my transmission mount and I'll start looking for a front drive shaft.

Look closely when the diff is drained you will see at first the silvery color metal come out that was sitting at the bottom. The fluid changes color a second later. The cover should have been removed to inspect the gears and clean the magnet.

Yeah, maybe so, but it's running fine now and I just don't want to cause any additional problems (If it ain't broke...). But thanks for the advice, I'll check the fluid again in the Spring and see if it's really dirty again.

 

[mubai]

I was really considering a new truck, with 193k on it and the vibration and some minor other issues. Now that I've been driving it for awhile with the new u-joint its like new again!!! Thanks again for the help!!