Excess vibrations?

[pods8]

I think I'm getting excess vibrations/play in my drive line. When doing 75mph and such at times my four wheel drive shift leaver (on the floor) will rock around a good couple inches which seems excessive. Counsel cup holders will also bounce around too. This is on flat expressway so its not the road transferring things up. Nothing notable happened to cause this and I'm just noticing it since I'm actually getting out in areas of WA where one can travel at such speeds (previous trips had been in 60mph zones for the most part). A quick inspection underneath doesn't show any obviously worn u joints or a freshly thrown drive shaft weight, etc. Any thoughts on what to check more in depth and how to do so in a driveway setting if possible?

New potential for a bigger trip this summer is coming around and I need to flush out as many gremlins as possible...

 

[pvstoy]

A quick inspection underneath doesn't show any obviously worn u joints or a freshly thrown drive shaft weight, etc.

You can't tell by looking at U-joints. Un weight the rear so the wheels will spin free. At both ends of the driveshaft see if the u-joints are loose or very tight. If you have exxesive play then replace them. Too tight means that they can be dried out and causing binding. If you have grease fittings get some in there. If not take the drive shaft off and have the U-joints replaced and then balanced.

 

[pvstoy]

Have you tried putting it in netural?

Does it feel like tires that are causing the vibration?

Hard to judge from here without being there.

 

[pods8]

You can't tell by looking at U-joints. Un weight the rear so the wheels will spin free. At both ends of the driveshaft see if the u-joints are loose or very tight. If you have exxesive play then replace them. Too tight means that they can be dried out and causing binding. If you have grease fittings get some in there. If not take the drive shaft off and have the U-joints replaced and then balanced.

All I've done so far was the try and shake the u-joints looking for gross wear. I currently still have the stock sealed type u joints so no grease fittings.

I have no issue on replacing the joints if others are confirming they or the drive shaft could be the likely culprit but I'd like to make sure I'm not over looking something like a mount or such wearing out (not really sure how the check those other than visually look for structural compromise or maybe leverage on them with a crow bar to check how much they move??).

Have you tried putting it in netural?

Does it feel like tires that are causing the vibration?

Hard to judge from here without being there.

Haven't tried putting it in neutral.

If you ask me it tends to feel like its more so in the drive line because it feels like its emanating from there into the counsel and such as opposed to the tires shaking everything and thus rattling the shifter as well. Also the steering wheel and steering doesn't really feel affected.

 

[EdoHart]

After checking U-joints and drive shaft balance, I would look at engine and/or transmission mounts. Then the pin holding the axle in place on the leaf spring.

Your signature doesn't include a lift, but if you have one, that can exacerbate some problems.

 

[pvstoy]

If you do the U-Joints yourself....mark everything how it came apart and make sure the phasing is correct for the front - rear U-Joints.

 

[pods8]

After checking U-joints and drive shaft balance, I would look at engine and/or transmission mounts. Then the pin holding the axle in place on the leaf spring.

Your signature doesn't include a lift, but if you have one, that can exacerbate some problems.

I'm still unsure how to really inspect the engine/trans mounts other than visually looking for tears and maybe applying some force against them with a crow bar. That sound legit or anyone have other directions?

No lift.

If you do the U-Joints yourself....mark everything how it came apart and make sure the phasing is correct for the front - rear U-Joints.

I'm planning to call the drive shaft place and see what it'd cost to have them pull the shaft for checking the balance and then installing fresh joints. If its under $100 labor I'll likely just have it done, otherwise I'd likely do it.

However I'm not sure what you mean by the phasing? I'm generally a self taught grease monkey and in the past I've just removed u joints and swapped the new one in place...

 

[EdoHart]

I'm self taught too, so take caution in whatever I say.

I think the way you describe checking the mounts sounds right. I doubt that is where the vibration is coming from, but I was thinking about things that might change your drive line angles.

By phasing, I think Patrick means how the mounting tabs for the U-joints line up at either end of the drive shaft relative to each other. If you don't remove the slip yoke from the drive shaft, I don't see how you would get it out of phase.

http://www.custompistols.com/cars/articles/ts_ujoints.htm explains it a lot better than I can.

 

[pvstoy]

Thanks Ed, That is what I’m talking about for “Phasing” Just follow the bottom of the link that was provided. I all ways make reference marks when things come off.

Most front drive shafts are not balanced very well. What I have done in the past is pull the rear shaft and go for a drive in four wheel drive high (front wheel only) and see if the vibration is still there. But if you have an output shaft that there is a slip into the transfer case then by pulling it you will have oil coming out.

Motor and transmission mounts you can take a floor jack and jack up on the engine or trans and see if the rubber is separated. Careful on punching holes or warping the pans and causing leaks or other problems.

Wish I was there to diagnose it with you.

 

[Barko1]

My F250 was out of phase but it was caught when I had a mechanic give it a good going over so it happens.


I'm self taught too, so take caution in whatever I say.

I think the way you describe checking the mounts sounds right. I doubt that is where the vibration is coming from, but I was thinking about things that might change your drive line angles.

By phasing, I think Patrick means how the mounting tabs for the U-joints line up at either end of the drive shaft relative to each other. If you don't remove the slip yoke from the drive shaft, I don't see how you would get it out of phase.

http://www.custompistols.com/cars/articles/ts_ujoints.htm explains it a lot better than I can.

 

[camelracer]

According to the Dodge manual a speed specific vibration is not usually caused by drive shaft imbalance. Speed specific drive shaft vibration is usually the result of bad u-joints or drive shaft angles.
I'm not sure about your 1500 but my 2500 doesn't have hubs or an axle disconnect so the front drive shaft is always turning. If that is the case with your rig I would remove the front shaft and see if the problem goes away. The front shaft has a CV joint which has more parts to go bad.

Dick

 

[pods8]

According to the Dodge manual a speed specific vibration is not usually caused by drive shaft imbalance. Speed specific drive shaft vibration is usually the result of bad u-joints or drive shaft angles.
I'm not sure about your 1500 but my 2500 doesn't have hubs or an axle disconnect so the front drive shaft is always turning. If that is the case with your rig I would remove the front shaft and see if the problem goes away. The front shaft has a CV joint which has more parts to go bad.

Dick

I don't know if I'd call it speed specific as much as amplified at higher speeds... The last trip out I had it up into the 75-80 range and it became more noticable/annoying/of concern. I've never had it going faster than that but I'd assume it would continue with that trend.

 

[pods8]

http://www.custompistols.com/cars/articles/ts_ujoints.htm explains it a lot better than I can.

This truck has a slip yolk into the transfer case so if I'm understanding this link correctly there is no way to get out of phase on this design because you can't change the rotations of the two U-joints on the shaft relative to each other (solid drive shaft). Did I understand that correctly?

 

[EdoHart]

This truck has a slip yolk into the transfer case so if I'm understanding this link correctly there is no way to get out of phase on this design because you can't change the rotations of the two U-joints on the shaft relative to each other (solid drive shaft). Did I understand that correctly?

That sounds correct to me.

 

[camelracer]

I hate to bring up this subject again but I noticed your truck has air bags. Have you changed the ride height recently which can change the drive shaft angles?

Dick

 

[Bat]

Driveline angles usually have problems when the lift is above 4". I would rotate the tires front to back to see if it does anything. I know you said it does not affect the steering wheel but when ever I have vibrations problems it is the first thing I do to is to eliminate the tires.

 

[pods8]

I hate to bring up this subject again but I noticed your truck has air bags. Have you changed the ride height recently which can change the drive shaft angles?

Dick

No the bags have the truck sitting around unloaded stance.

Driveline angles usually have problems when the lift is above 4". I would rotate the tires front to back to see if it does anything. I know you said it does not affect the steering wheel but when ever I have vibrations problems it is the first thing I do to is to eliminate the tires.

That is doable.

 

[pods8]

I think this is resolved, I took it on a quick drive down 5mi of highway in the 70mph zone and all appeared well. Next trip out will confirm things one way or another.

Short version: Appears one of the tires that was on the rear had a bunch of fix a flat in it from the previous owner that I was unaware of and it was throwing off the balance some.

Long version:
I took the truck in two Saturdays ago for 4 tire balance and rotation. Instead of taking the 1hr they promised they took over 2hrs but they gave me a $20 discount. I leave the place and loop out on the highway to check things out and I can't even go 55mph without major steering wheel vibrations. I get off and go home thinking I tossed a weight or something. I called to let them know I'd be back in.

The following Monday I was near the place so I took it in but they were booked for the evening but checked all the lug torques to make sure there wasn't any issues (however the scheduler did this not the tech).

The following Friday I go back in and drop off my truck and head out for a run down a nearby trail. I get back and get called in to see an issue. Apparently all the lugs are bulged and a socket no longer fits. The stock lugs are cheap two piece designs (insert dodge joke here ) in which a decorative metal cap is pressed over the lug. Well those caps got spun/deformed and the flat part of the hex had lifted up (remember when the scheduler checked the torques and not the mechanic, he likely used an over sized socket). There were no managers around, it was too late to take care of things that evening, and I was all sweaty from running so I told them to drop my truck and I'd be back. We still haven't approached why I have vibrations and now all my lugs are trashed.

Next morning I called dodge to get a cost on lugs (even though I was going to buy solid 1 piece after market lugs but I needed to point out its actually cheaper to do so when I went back in) at they wanted $7 something per lug for those pieces of crap. $1.75 a lug later for the after market ones I was back at the tire place with 20 new lugs, a receipt for reimbursement, and was chatting with the manager. Grabbed my bike out of the back, told them to have fun getting the old ones off and told them to call me when they figured things out. Pedaled home and watched the tour de france till they called and filled me in on things. They got all the lugs changed out and it turns out one of the tires that was rotated to the front was giving a lot of balancing issues and then they discovered it had a ton of fix a flat in it that was sluffing around and throwing the machine off. So they cleaned it out and got everything all mounted up again. Why the original tech didn't notice this issue I don't know but now things appear to be in good shape and I've got solid lug nuts to avoid future issues.

 

[Bat]

 

[EdoHart]

...The stock lugs are cheap two piece designs (insert dodge joke here ) in which a decorative metal cap is pressed over the lug. Well those caps got spun/deformed ...

Yeah, those lug nuts really suck. I've had some of the metal caps come off and others get spun/deformed like yours. Part of my tire changing kit includes a breaker bar and the correct socket sizes for the nuts both with and without the cap.

I'm glad the issue has been fixed.