what would cause....

[muddeprived]

...a thumping tire?

Here's something I noticed. This is the second time that this happened. I get a set of tires, used or new, and have them balanced and mounted at NTB. The initial drive is perfect. No shakes, no shimmies, just a smooth ride. After a couple weeks I decide to rotate them. All of a sudden i have thumping from up front. It's a constant thumping that increases with speed and It's pretty obvious that it's the tires that i just put up front. I get a bad shake from 55-65 too. It shakes the entire jeep. I don't get it. I didn't off road or do anything stupid with the tires.

This happened with my new set of trxus mt's and now with my was-perfect Mickey Thompson MTZ's.

:confused::confused:

[Mudderoy]

...a thumping tire?

Here's something I noticed. This is the second time that this happened. I get a set of tires, used or new, and have them balanced and mounted at NTB. The initial drive is perfect. No shakes, no shimmies, just a smooth ride. After a couple weeks I decide to rotate them. All of a sudden i have thumping from up front. It's a constant thumping that increases with speed and It's pretty obvious that it's the tires that i just put up front. I get a bad shake from 55-65 too. It shakes the entire jeep. I don't get it. I didn't off road or do anything stupid with the tires.

This happened with my new set of trxus mt's and now with my was-perfect Mickey Thompson MTZ's.

:confused::confused:

I doubt this would happen in two weeks, but have you checked for cupping?

[muddeprived]

I doubt this would happen in two weeks, but have you checked for cupping?

Yeah i just did this morning. I drove home from pittsburgh yesterday and it was an awful ride so i checked the front and rear for cupping but can't seem to see anything abnormal. I plan to switch tires with my gf's bro and see if the thumping is gone then I'll know for sure if it's the tires. This just sucks cuz i was extremely pleased with these tires.

What would cause the rear tires to cup so quickly? I have OME 2" springs with OME AAL and RC 2" shackles. It's bolted up right, the axle ain't tilted or anything like that, and I can't think of anything else to mention. Oh I do have brand new shocks on too.


:headbag:

[Jeepster19]

:thumbsup:I don't know if this will help but you can check.It may be a bad shock,I had a 65 galaxie with the same problem.Check to see if you have oil seepage coming out of the shock,it's worth a look.

[muddeprived]

:thumbsup:I don't know if this will help but you can check.It may be a bad shock,I had a 65 galaxie with the same problem.Check to see if you have oil seepage coming out of the shock,it's worth a look.

That's funny. I edited my post to include "new shocks" cuz i forgot that shocks can cause cupping and then you posted this probably at the same time. Thanks though. :smiley-laughing021:

[Mudderoy]

I had cupping about 3 months after the lift and the tires. I changed out the wheel bearing assemblies (trying to fix something else) which FIXED the cupping problem. I had 110 on the WBA at the time. Recently I noticed a different kind of cupping on my front tires. I need to check to see if they are over inflated, plus I just got some nitro shocks to replace the hydro's that I got with the lift kit.

The first cupping was in the inside lugs of the front tires. The cupping I am seeing now is in the center.

So I'm over inflated or the wheels are hopping.

BTW, if you have time go have the balance checked. I think NTB will do that for free. If not explain the problem you are having and I bet they'll do it for free. You may have some tires that are hard to keep balanced. Might be time for the air soft BBs.

[firehawk]

Have had the same type of thing happen to me after I had a set of tires rotated and balanced. They are smooth for a short time, and then they will do what you describe.

I go to Discount Tire here and they will do what they call "road force balance" to the tires. I don't know what is different from a "standard" balance, but the problem goes away after the road force balance.:confused:

Might try that.:thumbsup:

[Mudderoy]

Have had the same type of thing happen to me after I had a set of tires rotated and balanced. They are smooth for a short time, and then they will do what you describe.

I go to Discount Tire here and they will do what they call "road force balance" to the tires. I don't know what is different from a "standard" balance, but the problem goes away after the road force balance.:confused:

Might try that.:thumbsup:

I bet they put heavier weights on.

[firehawk]

I bet they put heavier weights on.

I figured they were putting weight on the tire to simulate it running on pavement, not sure though. Instead of simply just spinning the tire to balance it.

[muddeprived]

The thing is, there's no discount tire close by and no one does road force balancing either. There was a shop way up in pittsburgh but they charge $89 to balance them. F@%^ that, that's way too much.

I can see an out of balance tire shaking but i can't see it making a thumping noise.

[DETOURS]

In what manor are you rotating them?

DR to DF, PR to PF?

[BlueXJ]

Prolly a stupid question but here goes anyway. Why did youi decide to rotate them after such a short time? I personally never rotate tires and still get great wear from them. I have a theory that tires learn the job expected of them in the position they are originally mounted. If you move them they have to learn all over again and that causes excessive wear and other things( cupping, thumping and balance issues.) See I told you it was stupid.

[2000XJ]

There is a good chance that the one or both of the tires that were on the rear of the vehicle, which are now on the front of the vehicle, did not originally balance as well the first time they were mounted/balanced. Places tend to put the two most poorly balanced tires on the rear of the vehicle because then the driver is less likely to notice any shakes, wobbles, hopping, etc. Leaf springs also do a better job of dissipating any crappy balancing since they don't tend to flex as much as coils do.

Only 2 of my 33's are well-balanced, they ride up front. My two unbalanced 33's are mounted in the rear. I can't notice that they're not balanced regardless of how fast I'm going. They don't even wobble shake as far as I can tell from staring at them in my rear-view mirrors.

Get the two tires in the front rebalanced, and see if that resolves your issues.

[muddeprived]

In what manor are you rotating them?

DR to DF, PR to PF?

Rears straight forward, PF to DR and DF to PR. " X "

[muddeprived]

Prolly a stupid question but here goes anyway. Why did youi decide to rotate them after such a short time? I personally never rotate tires and still get great wear from them. I have a theory that tires learn the job expected of them in the position they are originally mounted. If you move them they have to learn all over again and that causes excessive wear and other things( cupping, thumping and balance issues.) See I told you it was stupid.

That's a good question. I dunno but i'm glad I did cuz I caught the problem. I'm doubting that rotating them this early caused the issue cuz it thumped on the drive after the rotation so that would say it was already thumping back there but i just never felt it.

[muddeprived]

There is a good chance that the one or both of the tires that were on the rear of the vehicle, which are now on the front of the vehicle, did not originally balance as well the first time they were mounted/balanced. Places tend to put the two most poorly balanced tires on the rear of the vehicle because then the driver is less likely to notice any shakes, wobbles, hopping, etc. Leaf springs also do a better job of dissipating any crappy balancing since they don't tend to flex as much as coils do.

Only 2 of my 33's are well-balanced, they ride up front. My two unbalanced 33's are mounted in the rear. I can't notice that they're not balanced regardless of how fast I'm going. They don't even wobble shake as far as I can tell from staring at them in my rear-view mirrors.

Get the two tires in the front rebalanced, and see if that resolves your issues.

But would out of balanced tires causa consistant thumping at slow speeds? I can feel it from 10 mph and on.

[Howler_GT]

I would normally say , "Collapsed Ply"

But in your case, I think the nut behind the wheel is loose. :smiley-laughing021:

[Bighorncrag]

Should never happen on new tires but a separated tire also behaves as you have described. Just a thought.

[BuckB91XJ]

Sounds like you have something skinning your front wheel weights off like the inside of the rim is too close to your tierod ends. That that out.

[muddeprived]

Sounds like you have something skinning your front wheel weights off like the inside of the rim is too close to your tierod ends. That that out.

But it was fine before? It's like the tires have a flat spot on them and makes them thump. I don't think the wheel weights would cause a tire to thump at 10 mph.

I'll go check it out anyways.

[muddeprived]

I rotated them back and the thumping and shaking is gone. It's obvious one or both of the rear tires having something wrong with them. I'll just keep them this way till they go bald.

[Mudderoy]

We were having a discussion about a problem with one of the engineers truck tires. He had a noise coming from his. Anyway one guy said he had a single cable break in his radial and it made a noise until he was on a long trip and the rest of the belt broke and seperated.

Not saying this is your problem, but it might be best to fight with the place that you got the tire. Get it replaced before it lets you down far from home, or 2 feet down in the mud, or on top of a rock pile.

At the very least I'd figure out which one (hopefully just one) and rotate it to the spare.

Just a thought.

[muddeprived]

We were having a discussion about a problem with one of the engineers truck tires. He had a noise coming from his. Anyway one guy said he had a single cable break in his radial and it made a noise until he was on a long trip and the rest of the belt broke and seperated.

Not saying this is your problem, but it might be best to fight with the place that you got the tire. Get it replaced before it lets you down far from home, or 2 feet down in the mud, or on top of a rock pile.

At the very least I'd figure out which one (hopefully just one) and rotate it to the spare.

Just a thought.

Thanks for the tip. I bought these used with only 3k on them ($500 ;)). No option to return them.

[Mudderoy]

I can delete this post and you can put them up for sale here. :rotfl2:

[muddeprived]

I can delete this post and you can put them up for sale here. :rotfl2:

I wish i could. This is my 4th set of tires since i got the jeep. I think i'm done swapping tires for at least another year. :rotfl2:

[2000XJ]

I hear ya, I'm on my 5 set of tires, and 4th set of rims on my burgundy XJ. Crazy how that happened. At one points I had 15 tires and rims between my shed and my XJ.

[muddeprived]

I hear ya, I'm on my 5 set of tires, and 4th set of rims on my burgundy XJ. Crazy how that happened. At one points I had 15 tires and rims between my shed and my XJ.

:smiley-laughing021: Reminds me of my TJ. I went through so many tires and wheels. I guess i'm just so picky and look for the best shoes to fit my needs. Turned out the LTB's and Kumho MT's (old design) were the best fit.

[Melissa]

Damn I'm feeling left out, I'm only on my third set of tires and second set of wheels in 6 years. I must be doing something wrong :)

[muddeprived]

Damn I'm feeling left out, I'm only on my third set of tires and second set of wheels in 6 years. I must be doing something wrong :)

or RIGHT........

[2000XJ]

or RIGHT........

Quoting for how true this statement is!! Don't waste so much money on rims and tires. In the end you'll end up scratching most of them when you wheel anyway.

[Melissa]

I guess I have been lucky, I still have the original stock wheels that came with my jeep when I bought it. The new stock wheels I have, I bought with brand new tires on them for $350. I plan to use the old wheels for winter studded tires.