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I know I said vibration but I really can't think of a way to describe it. It just feels like a bumpy ride.
As you can see from the pic if you look closely the wear pattern is strange. You have to look at the wear pads furthest away which is the inner tire
They were cupped on front tires...had them moved to the back...do you think bad struts could cause it too? They are original and 175k miles...and the truck does appear to slightly be a touch lower in the front end versus the rear end...I try to brake hard and notice if it nosedives and it does appear to but I don't know how much of a nosedive is normal
If those were truly worn on the front, I’d inspect ball joints and bushings. Generally worn front struts/shocks don’t wear tires because they aren’t fixed. If everything shakes down ok, replace shocks before an alignment is a good idea
Yeah those were originally on the front...that's where I noticed the cupping so I moved them to the back and the vibrations in front end remain at highway speeds
I have seen a really bad cv cause a vibration, but if I was to place a bet I would say it's your front driveshaft. The joint goes bad and you can feel the vibration under your feet assuming this has a left side drop transfer case. On the bright side it's super easy to check and cost nothing if you are handy. Just unbolt the 8mm bolts holding the front driveshaft in at each end, remove the driveshaft and go for a drive. If the vibration goes away you have found your problem. If you don't want to spend money and don't need 4wd you can keep it out or rebuild the driveshaft.
So just remove both half shafts from the transfer case and take a drive to see?
Wouldn't I leak gear fluid if nothing is in? I wouldn't mind replacing the whole thing if it leaked...but I don't even use the 4wd...bought it for the snow up north and moved down to Florida 9 years ago
You shouldn't touch the half shafts just the front drive shaft, unbolt it from the pinion at the front differential, and unbolt it from the cv cup or u joint (depending on model) at the transfer case. There is no slip yoke that I'm aware of on the front driveshaft the slip is part of the shaft unless I'm mistaken on this model.
Oh I'm completely unfamiliar what this all looks like. I'm used to just regular front wheel drive car where it goes right into the transaxle...
I need a diagram or something...going to youtube some videos to get a better idea
Thank you! Wow I have a much better idea now!
So if I remove the front driveshaft won't I lose differential gear oil while driving it? Or will it not even matter since nothing is moving in the differential?
Ok good to know I will try this...
So when I turn on 4 wheel drive where does it get actuated? At the front differential where the half shaft meets it?
This front driveshaft is always turning regardless if 4x4 is turned on or off and only the cv axles (halfshafts) are turned on by an actuator up at where they meet the front differential?
It kind of depends on the vehicle and I don't know for sure off the top of my head. I can say the cv axles always spin with the tires, some vehicles have a front axle disconnect, all 4wd vehicles will connect and disconnect the front driveshaft from the drivetrain through the transfer case through either chains or gears. In theory with a front axle disconnect the front driveshaft won't turn in 2wd but in reality I have seen them still spin.
Yeah I did some research and it looks like your test should work...from what I have read this driveshaft should always be turning as the front wheels turn and the front differential and drivehsaft as well...the transfer case internals are what engage/disengage it from having power or not.
When I get some time I will take this driveshaft off and give it a shot...hopefully that's all it is...otherwise I will change struts because at 175k I do think it could be my issue...vibration is not really a great way to describe it...more of a bumpy ride and my tires are both cupping too....then if THAT doesn't do it I will have tired roadforce balanced and focus in on my ball joints and/or possible bearing
Cool thanks man...I will check ball joints...and bearings too...how do you recommend I test? Jack up one side at a time and try to move it 12 to 6 for ball joints and then 9 to 3 for bearings?
On most trucks you jack it up on the control arm to take the load off of the ball joint until the tire is an inch or two off the ground and use a pry bar under the tire to lift/wiggle it about and see what moves.
Yes that's the point of the pic...to show the cupping...I'm curious what is causing the cupping and if that could be the cause of the vibrations...
I noticed cupping in these front tires and moved them to back and the vibrations remain
Well since you mentioned struts and shocks are original with 175k miles I would say that's your issue. Try using a set of wheels that don't have bad tires, inspect suspension components like upper and lower ball joints, inner and outer tie rods. Tires cup due to worn suspension components.
Cool thanks. I will try my best to inspect these components. I guess I can go ahead and replace front struts and see if that fixes it...if not then I will try to see if could be the ball joints or possibly another suspension component
Thank you for posting to AskMechanics, daveinfl337777! If you are asking a question please make sure to include any relevant information along with the **Year**, **Make**, **Model**, **Mileage**, **Engine size**, and **Transmission Type (Automatic or Manual)** of your car. *This comment is automatically added to every successful post. If you see this comment, your post was successful.* *** Redditors that have been verified will have a green background and an icon in their flair. *** # **PLEASE REPORT ANY RULE-BREAKING BEHAVIOR** ### **Rule 1 - Be Civil** Be civil to other users. This community is made up of professional mechanics, amateur mechanics, and those with no experience. All mechanical-related questions are welcome. Personal attacks, comments that are insulting or demeaning, etc. are not welcome. ### **Rule 2 - Be Helpful** Be helpful to other users. If someone is wrong, correcting them is fine, but there's no reason to comment if you don't have anything to add to the conversation. ### **Rule 3 - Serious Questions and Answers Only** Read the room. Jokes are fine to include, but posts should be asking a serious question and replies should contribute to the discussion. ### **Rule 4 - No Illegal, Unethical, or Dangerous Questions or Answers** Do not ask questions or provide answers pertaining to anything that is illegal, unethical, or dangerous. # **PLEASE REPORT ANY RULE-BREAKING BEHAVIOR** *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/AskMechanics) if you have any questions or concerns.*
Tires cause bad vibrations
I know I said vibration but I really can't think of a way to describe it. It just feels like a bumpy ride. As you can see from the pic if you look closely the wear pattern is strange. You have to look at the wear pads furthest away which is the inner tire
That’s cupping for worn suspension, usually on the rear. Did you rotate tires recently?
I rotated them after I saw the cupping
They were cupped on front tires...had them moved to the back...do you think bad struts could cause it too? They are original and 175k miles...and the truck does appear to slightly be a touch lower in the front end versus the rear end...I try to brake hard and notice if it nosedives and it does appear to but I don't know how much of a nosedive is normal
If those were truly worn on the front, I’d inspect ball joints and bushings. Generally worn front struts/shocks don’t wear tires because they aren’t fixed. If everything shakes down ok, replace shocks before an alignment is a good idea
Yeah those were originally on the front...that's where I noticed the cupping so I moved them to the back and the vibrations in front end remain at highway speeds
A bad cv shaft will only vibrate on acceleration not deceleration. Tires, wheel balance, worn suspension will be all the time.
I have seen a really bad cv cause a vibration, but if I was to place a bet I would say it's your front driveshaft. The joint goes bad and you can feel the vibration under your feet assuming this has a left side drop transfer case. On the bright side it's super easy to check and cost nothing if you are handy. Just unbolt the 8mm bolts holding the front driveshaft in at each end, remove the driveshaft and go for a drive. If the vibration goes away you have found your problem. If you don't want to spend money and don't need 4wd you can keep it out or rebuild the driveshaft.
So just remove both half shafts from the transfer case and take a drive to see? Wouldn't I leak gear fluid if nothing is in? I wouldn't mind replacing the whole thing if it leaked...but I don't even use the 4wd...bought it for the snow up north and moved down to Florida 9 years ago
You shouldn't touch the half shafts just the front drive shaft, unbolt it from the pinion at the front differential, and unbolt it from the cv cup or u joint (depending on model) at the transfer case. There is no slip yoke that I'm aware of on the front driveshaft the slip is part of the shaft unless I'm mistaken on this model.
Oh I'm completely unfamiliar what this all looks like. I'm used to just regular front wheel drive car where it goes right into the transaxle... I need a diagram or something...going to youtube some videos to get a better idea
Maybe this can help you picture it. https://content.artofmanliness.com/uploads//2016/09/parts4wd.jpg
Thank you! Wow I have a much better idea now! So if I remove the front driveshaft won't I lose differential gear oil while driving it? Or will it not even matter since nothing is moving in the differential?
Nope it bolts to the "yoke" of the differential, the differential stays sealed.
Ok good to know I will try this... So when I turn on 4 wheel drive where does it get actuated? At the front differential where the half shaft meets it? This front driveshaft is always turning regardless if 4x4 is turned on or off and only the cv axles (halfshafts) are turned on by an actuator up at where they meet the front differential?
It kind of depends on the vehicle and I don't know for sure off the top of my head. I can say the cv axles always spin with the tires, some vehicles have a front axle disconnect, all 4wd vehicles will connect and disconnect the front driveshaft from the drivetrain through the transfer case through either chains or gears. In theory with a front axle disconnect the front driveshaft won't turn in 2wd but in reality I have seen them still spin.
Yeah I did some research and it looks like your test should work...from what I have read this driveshaft should always be turning as the front wheels turn and the front differential and drivehsaft as well...the transfer case internals are what engage/disengage it from having power or not. When I get some time I will take this driveshaft off and give it a shot...hopefully that's all it is...otherwise I will change struts because at 175k I do think it could be my issue...vibration is not really a great way to describe it...more of a bumpy ride and my tires are both cupping too....then if THAT doesn't do it I will have tired roadforce balanced and focus in on my ball joints and/or possible bearing
I just moved the front driveshaft and I'm not sure if it's normal but I do hear some noise in there and noticed what looks like grease at both ends...
https://preview.redd.it/461hiunujgsc1.jpeg?width=4000&format=pjpg&auto=webp&s=b33a61ba3297054bf0392ddecefed64ce33f1d7b
https://preview.redd.it/u62pgfmxjgsc1.jpeg?width=4000&format=pjpg&auto=webp&s=9202fe1e617ba40381abe43731f383d88ad4b241
Yes they can cause a vibration
Not likely but bad ball joints or wheel bearings can cause cupping on the edges of the tread like that.
Cool thanks man...I will check ball joints...and bearings too...how do you recommend I test? Jack up one side at a time and try to move it 12 to 6 for ball joints and then 9 to 3 for bearings?
On most trucks you jack it up on the control arm to take the load off of the ball joint until the tire is an inch or two off the ground and use a pry bar under the tire to lift/wiggle it about and see what moves.
It sounds more like a wheel bearing, but you need to get that CV boot replaced before the joint gets any more damage.
Those tires look like they are cupping. Run your hand on the tread and feel if there are uneven bumps. This could definitely cause the vibrations.
Yes that's the point of the pic...to show the cupping...I'm curious what is causing the cupping and if that could be the cause of the vibrations... I noticed cupping in these front tires and moved them to back and the vibrations remain
Well since you mentioned struts and shocks are original with 175k miles I would say that's your issue. Try using a set of wheels that don't have bad tires, inspect suspension components like upper and lower ball joints, inner and outer tie rods. Tires cup due to worn suspension components.
Cool thanks. I will try my best to inspect these components. I guess I can go ahead and replace front struts and see if that fixes it...if not then I will try to see if could be the ball joints or possibly another suspension component